Effects of climate change#Extreme storms

{{Further|Global surface temperature|Instrumental temperature record|Heat wave||}}

File:Change in Average Temperature With Fahrenheit.svg has warmed the most, and temperatures on land have generally increased more than sea surface temperatures.{{Cite web |title=GISS Surface Temperature Analysis (v4) |url=https://data.giss.nasa.gov/gistemp/maps/index_v4.html |access-date=12 January 2024 |website=NASA}}]]

Global warming affects all parts of Earth's climate system.{{Cite book|last1=Kennedy|first1=John|url=https://library.wmo.int/doc_num.php?explnum_id=5789|title=WMO statement on the State of the Global Climate in 2018|last2=Ramasamy|first2=Selvaraju|last3=Andrew|first3=Robbie|last4=Arico|first4=Salvatore|last5=Bishop|first5=Erin|last6=Braathen|first6=Geir|publisher=Chairperson, Publications Board, World Meteorological Organization|year=2019|isbn=978-92-63-11233-0|location=Geneva|page=6|access-date=24 November 2019|archive-url=https://web.archive.org/web/20191112010343/https://library.wmo.int/doc_num.php?explnum_id=5789|archive-date=12 November 2019|url-status=live}} Global surface temperatures have risen by {{Convert|1.1|C-change}}. Scientists say they will rise further in the future.{{cite book|url=https://www.ipcc.ch/report/ar6/syr/downloads/report/IPCC_AR6_SYR_SPM.pdf|chapter=Summary for Policymakers|title=Synthesis report of the IPCC Sixth Assessment Report|year=2023|at=A1, A4}}{{cite report|url=https://library.wmo.int/doc_num.php?explnum_id=11178|title=State of the Global Climate 2021|publisher=World Meteorological Organization|year=2022|page=2|access-date=23 April 2023|archive-date=18 May 2022|archive-url=https://web.archive.org/web/20220518083042/https://library.wmo.int/doc_num.php?explnum_id=11178|url-status=dead}} The changes in climate are not uniform across the Earth. In particular, most land areas have warmed faster than most ocean areas. The Arctic is warming faster than most other regions. Night-time temperatures have increased faster than daytime temperatures.{{cite journal |last1=Davy |first1=Richard |last2=Esau |first2=Igor |last3=Chernokulsky |first3=Alexander |last4=Outten |first4=Stephen |last5=Zilitinkevich |first5=Sergej |title=Diurnal asymmetry to the observed global warming |journal=International Journal of Climatology |date=January 2017 |volume=37 |issue=1 |pages=79–93 |doi=10.1002/joc.4688 |bibcode=2017IJCli..37...79D |doi-access=free }} The impact on nature and people depends on how much more the Earth warms.Schneider, S.H., S. Semenov, A. Patwardhan, I. Burton, C.H.D. Magadza, M. Oppenheimer, A.B. Pittock, A. Rahman, J.B. Smith, A. Suarez and F. Yamin, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter19-1.pdf Chapter 19: Assessing key vulnerabilities and the risk from climate change]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 779-810.{{rp|787}}

Scientists use several methods to predict the effects of human-caused climate change. One is to investigate past natural changes in climate.{{Cite web|last=Joyce|first=Christopher|date=30 August 2018|title=To Predict Effects Of Global Warming, Scientists Looked Back 20,000 Years|url=https://www.npr.org/2018/08/30/643342003/to-predict-effects-of-global-warming-scientists-looked-back-20-000-years|url-status=live|archive-url=https://web.archive.org/web/20191229182055/https://www.npr.org/2018/08/30/643342003/to-predict-effects-of-global-warming-scientists-looked-back-20-000-years|archive-date=29 December 2019|access-date=29 December 2019|website=NPR}} To assess changes in Earth's past climate scientists have studied tree rings, ice cores, corals, and ocean and lake sediments.{{citation|author=Overpeck, J.T.|title=NOAA Paleoclimatology Global Warming – The Story: Proxy Data|date=20 August 2008|url=http://www.ncdc.noaa.gov/paleo/globalwarming/proxydata.html|archive-url=https://web.archive.org/web/20170203204629/https://www.ncdc.noaa.gov/paleo/globalwarming/proxydata.html|publisher=NOAA Paleoclimatology Program – NCDC Paleoclimatology Branch|access-date=20 November 2012|archive-date=3 February 2017|url-status=live}} These show that recent temperatures have surpassed anything in the last 2,000 years.[https://phys.org/news/2019-07-20th-century-hottest-years.html The 20th century was the hottest in nearly 2,000 years, studies show] {{Webarchive|url=https://web.archive.org/web/20190725190643/https://phys.org/news/2019-07-20th-century-hottest-years.html|date=25 July 2019}}, 25 July 2019 By the end of the 21st century, temperatures may increase to a level last seen in the mid-Pliocene. This was around 3 million years ago.Nicholls, R.J., P.P. Wong, V.R. Burkett, J.O. Codignotto, J.E. Hay, R.F. McLean, S. Ragoonaden and C.D. Woodroffe, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter6-1.pdf Chapter 6: Coastal systems and low-lying areas]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 315-356.{{rp|322}} At that time, mean global temperatures were about {{Convert|2|-|4|C-change}} warmer than pre-industrial temperatures. The global mean sea level was up to {{convert|25|m}} higher than it is today.Oppenheimer, M., B.C. Glavovic , J. Hinkel, R. van de Wal, A.K. Magnan, A. Abd-Elgawad, R. Cai, M. Cifuentes-Jara, R.M. DeConto, T. Ghosh, J. Hay, F. Isla, B. Marzeion, B. Meyssignac, and Z. Sebesvari, 2019: [https://www.ipcc.ch/site/assets/uploads/sites/3/2022/03/06_SROCC_Ch04_FINAL.pdf Chapter 4: Sea Level Rise and Implications for Low-Lying Islands, Coasts and Communities]. In: [https://www.ipcc.ch/srocc/ IPCC Special Report on the Ocean and Cryosphere in a Changing Climate] [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 321–445. {{doi|10.1017/9781009157964.006}}.{{rp|323}} The modern observed rise in temperature and {{CO2}} concentrations has been rapid. Even abrupt geophysical events in Earth's history do not approach current rates.Allen, M.R., O.P. Dube, W. Solecki, F. Aragón-Durand, W. Cramer, S. Humphreys, M. Kainuma, J. Kala, N. Mahowald, Y. Mulugetta, R. Perez, M.Wairiu, and K. Zickfeld, 2018: [https://www.ipcc.ch/site/assets/uploads/sites/2/2022/06/SR15_Chapter_1_HR.pdf Chapter 1: Framing and Context]. In: [https://www.ipcc.ch/sr15/ Global Warming of 1.5 °C. An IPCC Special Report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty] [Masson-Delmotte, V., P. Zhai, H.-O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. Waterfield (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 49-92. {{doi|10.1017/9781009157940.003}}.{{rp|54}}

How much the world warms depends on human greenhouse gas emissions and on how sensitive the climate is to greenhouse gases.{{cite book|title=Global Climate Change Impacts in the United States |editor=Thomas R. Karl |editor2=Jerry M. Melillo |editor3=Thomas C. Peterson |pages=22–24 |chapter=Global Climate Change |access-date=2 May 2013 |url=http://downloads.globalchange.gov/usimpacts/pdfs/climate-impacts-report.pdf |archive-url=https://web.archive.org/web/20191115033015/https://downloads.globalchange.gov/usimpacts/pdfs/climate-impacts-report.pdf |archive-date=15 November 2019 |url-status=live}} The more carbon dioxide ({{CO2}}) is emitted in the 21st century the hotter the world will be by 2100. For a doubling of greenhouse gas concentrations, the global mean temperature would rise by about {{Convert|2.5|-|4|C-change}}.{{Cite web|date=9 August 2021|title=In-depth Q&A: The IPCC's sixth assessment report on climate science|url=https://www.carbonbrief.org/in-depth-qa-the-ipccs-sixth-assessment-report-on-climate-science|access-date=12 February 2022|website=Carbon Brief }} If emissions of {{CO2}} stopped abruptly and there was no use of negative emission technologies, the Earth's climate would not start moving back to its pre-industrial state. Temperatures would stay at the same high level for several centuries. After about a thousand years, 20% to 30% of human-emitted {{CO2}} would remain in the atmosphere. The ocean and land would not have taken them. This would commit the climate to a warmer state long after emissions have stopped.{{Cite book|last1=Collins|first1=M.|title={{Harvnb|IPCC AR5 WG1|2013}}|last2=Knutti|first2=R.|last3=Arblaster|first3=J. M.|last4=Dufresne|first4=J.-L.|last5=Fichefet|first5=T.|last6=Friedlingstein|first6=P.|last7=Gao|first7=X.|last8=Gutowski|first8=W. J.|last9=Johns|first9=T.|year=2013|page=1104|chapter=Chapter 12: Long-term Climate Change: Projections, Commitments and Irreversibility|ref={{harvid|IPCC AR5 WG1 Ch12|2013}}|display-authors=4|access-date=3 January 2020|chapter-url=https://archive.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter12_FINAL.pdf|archive-url=https://web.archive.org/web/20191219013928/https://archive.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter12_FINAL.pdf|archive-date=19 December 2019|url-status=live|first12=C.|first13=A. J.|last13=Weaver|first14=M.|last14=Wehner|first10=G.|last11=Shongwe|first11=M.|last10=Krinner|last12=Tebaldi}}

With current mitigation policies the temperature will be about 2.7 °C (2.0–3.6 °C) above pre-industrial levels by 2100. It would rise by {{Convert|2.4|C-change}} if governments achieved all their unconditional pledges and targets. If all the countries that have set or are considering net-zero targets achieve them, the temperature will rise by around {{Convert|1.8|C-change}}. There is a big gap between national plans and commitments and the actions that governments have taken around the world.{{cite web |date=9 November 2021 |title=Temperatures |url=https://climateactiontracker.org/global/temperatures/ |archive-url=https://web.archive.org/web/20220126022845/https://climateactiontracker.org/global/temperatures/ |archive-date=26 January 2022 |work=Climate Action Tracker}}

File:20211109 Frequency of extreme weather for different degrees of global warming - bar chart IPCC AR6 WG1 SPM.svg events (for increasing degrees of global warming) are expected.IPCC, 2021: [https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM.pdf Summary for Policymakers]. In: [https://www.ipcc.ch/report/ar6/wg1/ Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US, pp. 3−32, {{doi|10.1017/9781009157896.001}}{{rp|18}}]]

The lower and middle atmosphere, where nearly all weather occurs, are heating due to the greenhouse effect.

{{cite web |last=Hausfather |first=Zeke |date=21 June 2017 |title=Study: Why troposphere warming differs between models and satellite data |url=https://www.carbonbrief.org/study-why-troposphere-warming-differs-between-models-and-satellite-data |access-date=19 November 2019 |website=Carbon Brief }}

Evaporation and atmospheric moisture content increase as temperatures rise. Water vapour is a greenhouse gas, so this process is a self-reinforcing feedback.

{{cite web |title=Climate change: evidence and causes {{!}} Royal Society |url=https://royalsociety.org/topics-policy/projects/climate-change-evidence-causes/basics-of-climate-change/ |access-date=19 November 2019 |website=royalsociety.org }}

The excess water vapour also gets caught up in storms. This makes them more intense, larger, and potentially longer-lasting. This in turn causes rain and snow events to become stronger and leads to increased risk of flooding. Extra drying worsens natural dry spells and droughts. This increases risk of heat waves and wildfires.{{Cite journal |last=Trenberth |first=Ke |date=2011 |title=Changes in precipitation with climate change |journal=Climate Research |volume=47 |issue=1 |pages=123–138 |doi=10.3354/cr00953 |bibcode=2011ClRes..47..123T |doi-access=free }} Scientists have identified human activities as the cause of recent climate trends. They are now able to estimate the impact of climate change on extreme weather events using a process called extreme event attribution. For instance such research can look at historical data for a region and conclude that a specific heat wave was more intense due to climate change.{{Cite journal |last1=Swain |first1=Daniel L. |last2=Singh |first2=Deepti |last3=Touma |first3=Danielle |last4=Diffenbaugh |first4=Noah S. |date=2020-06-19 |title=Attributing Extreme Events to Climate Change: A New Frontier in a Warming World |journal=One Earth |language=en |volume=2 |issue=6 |pages=522–527 |doi=10.1016/j.oneear.2020.05.011 |bibcode=2020OEart...2..522S |s2cid=222225686 |issn=2590-3322|doi-access=free }} In addition, the time shifts of the season onsets, changes in the length of the season durations have been reported in many regions of the world.Schwartz, M.D. and Reiter, B.E. (2000) Changes in North American spring. International Journal of Climatology, 20, 929–932.Hekmatzadeh, A.A., Kaboli, S. and Torabi Haghighi, A. (2020) New indices for assessing changes in seasons and in timing characteristics of air temperature. Theoretical and Applied Climatology, 140, 1247–1261. {{doi|10.1007/s00704-020-03156-w}}.Kozlov, M.V. and Berlina, N.G. (2002) Decline in the length of the summer season on the Kola Peninsula, Russia. Climatic Change, 54, 387–398Sparks, T.H. and Menzel, A. (2002) Observed changes in seasons: an overview. International Journal of Climatology, 22, 1715–1725.Aksu, H. (2022). A determination of season shifting across Turkey in the period 1965–2020. International Journal of Climatology, 42(16), 8232–8247. {{doi|10.1002/joc.7705}} As a result of changes in climatic patterns and rising global temperatures, extreme weather events like heatwaves and heavy precipitation are occurring more frequently and with increasing severity.{{Cite web |date=2022-10-24 |title=Effects of Climate Change - Impacts and Examples |url=https://www.nrdc.org/stories/what-are-effects-climate-change#environment |access-date=2024-12-07 |website=www.nrdc.org |language=en}}

{{See also|Heat wave|Effects of climate change on human health}}

File:1951+ Percent of global area at temperature records - Seasonal comparison - NOAA.svg

{{ multiple image | total_width=450

| image1 = 1960- Heat wave indicators - US.svg |caption1= US heat waves have increased in frequency, average duration, and intensity.

Also, heat wave seasons have grown in length.{{cite web |title=Climate Change Indicators: Heat Waves |url=https://www.epa.gov/climate-indicators/climate-change-indicators-heat-waves |publisher=U.S. Environmental Protection Agency (EPA) |archive-url=https://web.archive.org/web/20241007114317/https://www.epa.gov/climate-indicators/climate-change-indicators-heat-waves |archive-date=7 October 2024 |date=June 2024 |url-status=live }} EPA cites data source: NOAA, 2024.

| image2 = 1960- Annual average number of days spent in heat waves - US.svg |caption2= Over decades, the average number of days spent in heat waves in the U.S. annually has increased, based on increases in both the average annual number of heat waves and on their average durations.

}}

File:Map of increasing heatwave trends over the midlatitudes and Europe.webp

Heatwaves over land have become more frequent and more intense in almost all world regions since the 1950s, due to climate change. Heat waves are more likely to occur simultaneously with droughts. Marine heatwaves are twice as likely as they were in 1980.{{cite book |title=Climate Change 2021: The Physical Science Basis |publisher=Intergovernmental Panel on Climate Change |year=2021 |pages=8–10 |chapter=Summary for Policymakers |chapter-url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM_final.pdf |archive-url=https://web.archive.org/web/20211104175351/https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_SPM_final.pdf |archive-date=4 November 2021 |url-status=live}} Climate change will lead to more very hot days and fewer very cold days.IPCC, 2013: [https://www.climatechange2013.org/images/report/WG1AR5_SPM_FINAL.pdf Summary for Policymakers]. In: Climate Change 2013: The Physical Science Basis. Contribution of Working Group I to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change [Stocker, T.F., D. Qin, G.-K. Plattner, M. Tignor, S.K. Allen, J. Boschung, A. Nauels, Y. Xia, V. Bex and P.M. Midgley (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US.{{rp|7}} There are fewer cold waves.{{rp|8}}

Experts can often attribute the intensity of individual heat waves to global warming. Some extreme events would have been nearly impossible without human influence on the climate system. A heatwave that would occur once every ten years before global warming started now occurs 2.8 times as often. Under further warming, heatwaves are set to become more frequent. An event that would occur every ten years would occur every other year if global warming reaches {{Convert|2|C-change}}.{{Cite journal |last1=Clarke |first1=Ben |last2=Otto |first2=Friederike |last3=Stuart-Smith |first3=Rupert |last4=Harrington |first4=Luke |date=2022-06-28 |title=Extreme weather impacts of climate change: an attribution perspective |journal=Environmental Research: Climate |volume=1 |issue=1 |pages=012001 |doi=10.1088/2752-5295/ac6e7d |issn=2752-5295 |s2cid=250134589 |doi-access=free|hdl=10044/1/97290 |hdl-access=free }}

Heat stress is related to temperature.{{Cite news |last1=Bawden |first1=Anna |last2=Health |first2=Anna Bawden |last3= |first3= |date=2024-10-30 |title=Record levels of heat-related deaths in 2023 due to climate crisis, report finds |url=https://www.theguardian.com/environment/2024/oct/30/record-levels-of-heat-related-deaths-in-2023-due-to-climate-crisis-report-finds |access-date=2024-10-31 |work=The Guardian |language=en-GB |issn=0261-3077}} It also increases if humidity is higher. The wet-bulb temperature measures both temperature and humidity. Humans cannot adapt to a wet-bulb temperature above {{Convert|35|C}}. This heat stress can kill people. If global warming is kept below {{Convert|1.5|or|2|C-change}}, it will probably be possible to avoid this deadly heat and humidity in most of the tropics. But there may still be negative health impacts.{{Cite journal |last1=Zhang |first1=Yi |last2=Held |first2=Isaac |last3=Fueglistaler |first3=Stephan |date=8 March 2021 |title=Projections of tropical heat stress constrained by atmospheric dynamics |journal=Nature Geoscience |volume=14 |issue=3 |pages=133–137 |doi=10.1038/s41561-021-00695-3 |bibcode=2021NatGe..14..133Z |s2cid=232146008 |url=https://repository.library.noaa.gov/view/noaa/30706 }}{{Cite web |last=Milman |first=Oliver |date=8 March 2021 |title=Global heating pushes tropical regions towards limits of human livability |url=http://www.theguardian.com/science/2021/mar/08/global-heating-tropical-regions-human-livability |access-date=22 July 2022 |website=The Guardian }}

There is some evidence climate change is leading to a weakening of the polar vortex. This would make the jet stream more wavy.{{Cite web|last=NOAA|date=16 February 2022|title=Understanding the Arctic polar vortex|url=https://www.climate.gov/news-features/understanding-climate/understanding-arctic-polar-vortex|access-date=19 February 2022|website=www.climate.gov }} This would lead to outbursts of very cold winter weather across parts of Eurasia{{Cite web|website=Deutsche Welle|title=How global warming can cause Europe's harsh winter weather |date=11 February 2021|url=https://www.dw.com/en/cold-winter-global-warming-polar-vortex/a-56534450|access-date=15 December 2021 }} and North America and incursions of very warm air into the Arctic.{{cite news|date=2 September 2021|title=Climate change: Arctic warming linked to colder winters|work=BBC News|url=https://www.bbc.com/news/science-environment-58425526|url-status=live|access-date=20 October 2021|archive-url=https://web.archive.org/web/20211020112818/https://www.bbc.com/news/science-environment-58425526|archive-date=20 October 2021}}{{cite journal|last1=Cohen|first1=Judah|last2=Agel|first2=Laurie|last3=Barlow|first3=Mathew|last4=Garfinkel|first4=Chaim I.|last5=White|first5=Ian|date=3 September 2021|title=Linking Arctic variability and change with extreme winter weather in the United States|journal=Science|volume=373|issue=6559|pages=1116–1121|bibcode=2021Sci...373.1116C|doi=10.1126/science.abi9167|pmid=34516838 |s2cid=237402139}}{{Cite web|last=Douglas|first=Erin|date=14 December 2021|title=Winters get warmer with climate change. So what explains Texas' cold snap in February?|url=https://www.texastribune.org/2021/12/14/winter-weather-texas-climate-change/|access-date=15 December 2021|website=The Texas Tribune }} Some studies found a weakening of the AMOC by about 15% since 1950, causing cooling in the North Atlantic and warming in the Gulf Stream region.{{cite web |title=A Closer Look at the Weakening AMOC and Its Ramifications |url=https://climateadaptationplatform.com/a-closer-look-at-the-weakening-amoc-and-its-ramifications/ |website=Climate adaptation platform |access-date=12 December 2024}} Climate change is expected to weaken AMOC in all emissions scenarios{{cite book |title=Climate Change 2023: Synthesis Report. Contribution of Working Groups I, II and III to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |date=2023 |publisher=United Nations |location=Geneva, Switzerland |pages=18, 78 |url=https://www.ipcc.ch/report/ar6/syr/downloads/report/IPCC_AR6_SYR_FullVolume.pdf |access-date=21 November 2024}} and, in some high emissions scenarios, can bring it to collapse. This can result in cooling of some parts of Europe by up to 30 degrees and warming in the southern hemisphere.{{cite news |title=Dangers of Atlantic Ocean current collapse have been 'greatly underestimated', scientists warn |url=https://www.euronews.com/green/2024/10/24/this-tipping-point-would-be-catastrophic-for-europe-but-scientists-are-unsure-when-well-re |access-date=12 December 2024 |agency=Euronews |date=24 October 2024}}

{{Main|Effects of climate change on the water cycle}}Warming increases global average precipitation. Precipitation is when water vapour condenses out of clouds, such as rain and snow.{{rp|1057}} Higher temperatures increase evaporation and surface drying. As the air warms it can hold more water. For every degree Celsius it can hold 7% more water vapour.{{rp|1057}} Scientists have observed changes in the amount, intensity, frequency, and type of precipitation.{{citation |title=In {{harvnb|IPCC SREX|2012}} |page=8 |access-date=17 December 2012 |archive-url=https://web.archive.org/web/20190627001210/https://docs.google.com/file/d/0B1gFp6Ioo3akYklZcWkwWHJud00/edit?pli=1 |url-status=live |chapter=Summary for policymakers |chapter-url=https://docs.google.com/file/d/0B1gFp6Ioo3akYklZcWkwWHJud00/edit?pli=1 |archive-date=27 June 2019}} Overall, climate change is causing longer hot dry spells, broken by more intense rainfall.{{Cite book |last=Trenberth |first=Kevin E. |url=https://www.cambridge.org/core/product/identifier/9781108979030/type/book |title=The Changing Flow of Energy Through the Climate System |date=2022 |publisher=Cambridge University Press |isbn=978-1-108-97903-0 |edition=1 |doi=10.1017/9781108979030 |s2cid=247134757}}{{rp|151, 154}}

Climate change has increased contrasts in rainfall amounts between wet and dry seasons. Wet seasons are getting wetter and dry seasons are getting drier. In the northern high latitudes, warming has also caused an increase in the amount of snow and rain.{{rp|1057}} In the Southern Hemisphere, the rain associated with the storm tracks has shifted south. Changes in monsoons vary a lot. More monsoon systems are becoming wetter than drier. In Asia summer monsoons are getting wetter. The West African monsoon is getting wetter over the central Sahel, and drier in the far western Sahel.{{rp|1058}}

File:Wea02630 - Flickr - NOAA Photo Library.jpg submerged after Hurricane Katrina, September 2005]]

Storms become wetter under climate change. These include tropical cyclones and extratropical cyclones. Both the maximum and mean rainfall rates increase. This more extreme rainfall is also true for thunderstorms in some regions.{{Cite book|chapter=Chapter 11: Weather and climate extreme events in a changing climate

|last1 = Seneviratne| first1 = Sonia I.| last2 = Zhang| first2 = Xuebin| last3 = Adnan| first3 = M.|chapter-url= https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter11.pdf |display-authors=etal|title= Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate|year=2021

|publisher=Cambridge University Press|page=1519}} Furthermore, tropical cyclones and storm tracks are moving towards the poles. This means some regions will see large changes in maximum wind speeds.{{Cite journal |last1=Knutson |first1=Thomas |last2=Camargo |first2=Suzana J. |last3=Chan |first3=Johnny C. L. |last4=Emanuel |first4=Kerry |last5=Ho |first5=Chang-Hoi |last6=Kossin |first6=James |last7=Mohapatra |first7=Mrutyunjay |last8=Satoh |first8=Masaki |last9=Sugi |first9=Masato |last10=Walsh |first10=Kevin |last11=Wu |first11=Liguang |date=August 6, 2019 |title=Tropical Cyclones and Climate Change Assessment: Part II. Projected Response to Anthropogenic Warming |journal=Bulletin of the American Meteorological Society |volume=101 |issue=3 |pages=BAMS–D–18–0194.1 |doi=10.1175/BAMS-D-18-0194.1 |bibcode=2020BAMS..101E.303K |doi-access=free |hdl=1721.1/124705 |hdl-access=free }} Scientists expect there will be fewer tropical cyclones, but they expect their strength to increase. There has probably been an increase in the number of tropical cyclones that intensify rapidly. Meteorological and seismological data indicate a widespread increase in wind-driven global ocean wave energy in recent decades that has been attributed to an increase in storm intensity over the oceans due to climate change.{{cite journal |last1=Reguero |first1=B. |last2=Losada |first2=I. |last3=Mendez |first3=F. |title=A recent increase in global wave power as a consequence of oceanic warming |journal=Nature Communications |date=2019 |volume=10 |issue=1 |page=205 |doi=10.1038/s41467-018-08066-0|pmid=30643133 |pmc=6331560 |bibcode=2019NatCo..10..205R }}{{cite journal |last1=Bromirski |first1=P. |title=Climate-Induced Decadal Ocean Wave Height Variability\ From Microseisms: 1931–2021 |journal=Journal of Geophysical Research: Oceans |date=2023 |volume=128 |issue=8 |doi=10.1029/2023JC019722|bibcode=2023JGRC..12819722B |s2cid=260414378 |doi-access=free }}{{cite journal |last1=Aster |first1=R. |last2=Ringler |first2=A. |last3=Anthony |first3=R. |last4=Lee |first4=T. |title=Increasing ocean wave energy observed in Earth's seismic wavefield since the late 20th century |journal=Nature Communications |date=2023 |volume=14 |issue=1 |page=6984 |doi=10.1038/s41467-023-42673-w|pmid=37914695 |pmc=10620394 |bibcode=2023NatCo..14.6984A }} Atmospheric turbulence dangerous for aviation (hard to predict or that cannot be avoided by flying higher) probably increases due to climate change.{{cite news |last1=Stallard |first1=Esme |title=Is climate change making turbulence worse? |url=https://www.bbc.com/news/articles/cv22endle1no |access-date=23 May 2024 |agency=BBC |date=22 May 2024}}

{{ multiple image | total_width = 450

| image1 = Soil moisture and climate change.svg |caption1= The sixth IPCC Assessment Report included projections of changes in average soil moisture.

| image2 = California Drought Dry Lakebed 2009.jpg |caption2= A dry lakebed in California In 2022, the state was experiencing its most serious drought in 1,200 years, worsened by climate change.{{cite web |author=Irina Ivanova |date=2 June 2022 |title=California is rationing water amid its worst drought in 1,200 years |url=https://www.cbsnews.com/news/water-cutbacks-california-6-million-people-drought/ |access-date=2 June 2022 |publisher=CBS News}}

}}

Due to an increase in heavy rainfall events, floods are likely to become more severe when they do occur.{{rp|1155}} The interactions between rainfall and flooding are complex. There are some regions in which flooding is expected to become rarer. This depends on several factors. These include changes in rain and snowmelt, but also soil moisture.{{rp|1156}} Climate change leaves soils drier in some areas, so they may absorb rainfall more quickly. This leads to less flooding. Dry soils can also become harder. In this case heavy rainfall runs off into rivers and lakes. This increases risks of flooding.{{rp|1155}}

Climate change affects many factors associated with droughts. These include how much rain falls and how fast the rain evaporates again. Warming over land increases the severity and frequency of droughts around much of the world.{{Cite journal |last1=Cook |first1=Benjamin I. |last2=Mankin |first2=Justin S. |last3=Anchukaitis |first3=Kevin J. |date=2018-05-12 |title=Climate Change and Drought: From Past to Future |url=https://link.springer.com/article/10.1007/s40641-018-0093-2 |journal=Current Climate Change Reports |volume=4 |issue=2 |pages=164–179 |doi=10.1007/s40641-018-0093-2 |bibcode=2018CCCR....4..164C |s2cid=53624756 |issn=2198-6061}}Douville, H., K. Raghavan, J. Renwick, R.P. Allan, P.A. Arias, M. Barlow, R. Cerezo-Mota, A. Cherchi, T.Y. Gan, J. Gergis, D. Jiang, A. Khan, W. Pokam Mba, D. Rosenfeld, J. Tierney, and O. Zolina, 2021: [https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter08.pdf Chapter 8: Water Cycle Changes]. In [https://www.ipcc.ch/report/ar6/wg1/ Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US, pp. 1055–1210, {{doi|10.1017/9781009157896.010}}{{rp|1057}} In some tropical and subtropical regions of the world, there will probably be less rain due to global warming. This will make them more prone to drought. Droughts are set to worsen in many regions of the world. These include Central America, the Amazon and south-western South America. They also include West and Southern Africa. The Mediterranean and south-western Australia are also some of these regions.{{rp|1157}}

Higher temperatures increase evaporation. This dries the soil and increases plant stress. Agriculture suffers as a result. This means even regions where overall rainfall is expected to remain relatively stable will experience these impacts.{{rp|1157}} These regions include central and northern Europe. Without climate change mitigation, around one third of land areas are likely to experience moderate or more severe drought by 2100.{{rp|1157}} Due to global warming droughts are more frequent and intense than in the past.{{Cite web |date=2023-03-13 |title=Scientists confirm global floods and droughts worsened by climate change |url=https://www.pbs.org/newshour/science/scientists-confirm-global-floods-and-droughts-worsened-by-climate-change |access-date=2023-05-01 |website=PBS NewsHour |language=en-us}}

Several impacts make their impacts worse. These are increased water demand, population growth and urban expansion in many areas.{{Cite journal |last1=Mishra |first1=A. K. |last2=Singh |first2=V. P. |year=2011 |title=Drought modeling – A review |journal=Journal of Hydrology |volume=403 |issue=1–2 |pages=157–175 |bibcode=2011JHyd..403..157M |doi=10.1016/j.jhydrol.2011.03.049}} Land restoration can help reduce the impact of droughts. One example of this is agroforestry.Daniel Tsegai, Miriam Medel, Patrick Augenstein, Zhuojing Huang (2022) [https://www.unccd.int/resources/publications/drought-numbers Drought in Numbers 2022 - restoration for readiness and resilience], United Nations Convention to Combat Desertification (UNCCD)

{{Further|Wildfire#Climate change effects}}

File:1911- Wildfire disasters - worldwide.svg .]]

Climate change promotes the type of weather that makes wildfires more likely. In some areas, an increase of wildfires has been attributed directly to climate change. Evidence from Earth's past also shows more fire in warmer periods.{{cite web |last1=Jones |first1=Matthew |last2=Smith |first2=Adam |last3=Betts |first3=Richard |last4=Canadell |first4=Josep |last5=Prentice |first5=Collin |last6=Le Quéré |first6=Corrine |title=Climate Change Increases the Risk of Wildfires |url=https://sciencebrief.org/briefs/wildfires |access-date=16 February 2022 |website=ScienceBrief |archive-date=26 January 2024 |archive-url=https://web.archive.org/web/20240126143009/https://sciencebrief.org/briefs/wildfires |url-status=dead }} Climate change increases evapotranspiration. This can cause vegetation and soils to dry out. When a fire starts in an area with very dry vegetation, it can spread rapidly. Higher temperatures can also lengthen the fire season. This is the time of year in which severe wildfires are most likely, particularly in regions where snow is disappearing.{{Cite web |last=Dunne |first=Daisy |date=14 July 2020 |title=Explainer: How climate change is affecting wildfires around the world |url=https://www.carbonbrief.org/explainer-how-climate-change-is-affecting-wildfires-around-the-world |access-date=17 February 2022 |website=Carbon Brief }}

Weather conditions are raising the risks of wildfires. But the total area burnt by wildfires has decreased. This is mostly because savanna has been converted to cropland, so there are fewer trees to burn. Prescribed burning is an indigenous practice in the US and Australia. It can reduce wildfire burning.

The carbon released from wildfires adds to carbon dioxide in Earth's atmosphere and therefore contributes to the greenhouse effect. Climate models do not yet fully reflect this climate change feedback.{{rp|20}}

{{Further|Glacial earthquake#Global warming}}

In regions sensitive to climate change the frequency and intensity of eruptions will change as global warming increases. Glacier retreat and stronger precipitation can increase the chances for an eruption. As of 2024, government agencies are already addressing these changes and scientists are working to map the volcanoes most sensitive to climate change. The concerns regions are where glaciers are melting fast, and there are volcanoes heavily affected by precipitation. 716 volcanoes worldwide, may be affected by more extreme precipitation. Melting ice and extreme rainfall also increase secondary hazards, particularly lahars and disturb eruption forecasting by inducing ground displacements.{{cite web |last1=Pinel |first1=Virginie |last2=Aubry |first2=Thomas|title=Climate change will also have an impact on volcanic eruptions |url=https://www.polytechnique-insights.com/en/columns/planet/climate-change-will-also-have-an-impact-on-volcanic-eruptions/ |website=Polytechnique insights |publisher=INSTITUT POLYTECHNIQUE DE PARIS |access-date=12 December 2024}}

Earthquakes can be triggered by changes in the amount of stress on a fault in the Earth's crust. Strong rain, snow, drought and more pumping of groundwater by humans during droughts, can do it by increasing or reducing the weight of water on some pieces of the Earth's crust. So, as climate change will cause more extreme weather, it can induce more earthquakes. Glacier retreat reduce stress loads on Earth’s crust underneath, creating glacial earthquakes. Glacial earthquakes in Greenland for example, peak in frequency in the summer months and are increasing over time, possibly in response to global warming.{{cite web |last1=Blackett |first1=Matthew |title=Climate change could be triggering more earthquakes and volcanic eruptions. Here's how |url=https://www.weforum.org/stories/2023/08/climate-change-trigger-earthquakes-volcanoes/ |website=World Economic Forum |access-date=12 December 2024}}{{cite web |last1=Buis |first1=Alan |title=Can Climate Affect Earthquakes, Or Are the Connections Shaky? |url=https://science.nasa.gov/earth/climate-change/can-climate-affect-earthquakes-or-are-the-connections-shaky/ |website=NASA |access-date=12 December 2024}}

Sea level rise can also create pressure on tectonic faults, increasing risk for earthquakes.{{cite news |last1=Ravilious |first1=Kate |title=Terrawatch: how sea level changes can trigger earthquakes |url=https://www.theguardian.com/science/2023/apr/26/terrawatch-sea-level-changes-earthquakes-turkey |access-date=12 December 2024 |agency=The Guardian |date=26 April 2023}}{{cite web |last1=Irwing |first1=Katherine |title=Will we have more earthquakes because of climate change? |url=https://www.livescience.com/planet-earth/earthquakes/will-we-have-more-earthquakes-because-of-climate-change |website=Live Science |access-date=12 December 2024}}

In Greenland, the climate crisis triggered a landslide, which caused a mega-tsunami in September 2023. The event was so huge that the entire planet vibrated for nine days. Earthquake sensors around the world detected the Earth's vibration but the planetary-scale of the event was so unprecedented that at first scientists failed to understand it. Further investigation revealed that the culprit was collapse of a 1,200-metre-high mountain peak into the remote Dickson Fjord on September 16, 2023 after the glacier below the mountain melted to a sufficient degree. The collapse into the fjord, in turn, launched a wave 200 metres high, which caused repeated movement of water back and forth in the fjord, blasting seismic waves planet wide for nine days.The Guardian, 12 Sept. 2024 [https://www.theguardian.com/environment/2024/sep/12/entire-earth-vibrated-climate-triggered-mega-tsunami?CMP=Share_iOSApp_Other "Entire Earth Vibrated for Nine Days After Climate-Triggered Mega-Tsunami "Landslide in Greenland Caused Unprecedented Seismic Event that Shows Impact of Global Heating, Say Scientists]

File:WhereIsTheHeatOfGlobalWarming2023.svg

File:Co2 time series aloha 08-09-2023.jpg): Time series of atmospheric {{CO2}} at Mauna Loa (in parts per million volume, ppmv; red), surface ocean p{{CO2}} (μatm; blue) and surface ocean pH (green) at Ocean Station ALOHA in the subtropical North Pacific Ocean.{{Cite web |title=Atmospheric {{CO2}} and Ocean pH |url=https://cleanet.org/details/images/33568.html |access-date=2022-11-17 |website=cleanet.org}}{{Cite web |title=Quality of pH Measurements in the NODC Data Archives |url=https://www.pmel.noaa.gov/co2/story/Quality+of+pH+Measurements+in+the+NODC+Data+Archives |access-date=2023-12-18 |website=www.pmel.noaa.gov}}]]{{excerpt|Effects of climate change on oceans|paragraphs=1-3|file=no}}

File:1880- Global average sea level rise (SLR) - annually.svg and storm surge) occur.]]

File:2050 Projected sea level rise - United States coasts - NOAA.svg predicts different levels of sea level rise for coastlines within a single country.{{cite web |title=2022 Sea Level Rise Technical Report |url=https://oceanservice.noaa.gov/hazards/sealevelrise/sealevelrise-tech-report.html |publisher=National Ocean Service, National Oceanic and Atmospheric Administration (NOAA) |archive-url=https://web.archive.org/web/20221129070303/https://oceanservice.noaa.gov/hazards/sealevelrise/sealevelrise-tech-report.html |archive-date=November 29, 2022 |date=February 2022 |url-status=live }}]]

{{excerpt|sea level rise|paragraphs=1-2}}

{{See also|Special Report on the Ocean and Cryosphere in a Changing Climate}}

File:20210125 The Cryosphere - Floating and grounded ice - imbalance - climate change.png

File:2015-2100 Impacts of global warming on glaciers and sea level rise.svg

The cryosphere, the area of the Earth covered by snow or ice, is extremely sensitive to changes in global climate.[https://serc.carleton.edu/eslabs/cryosphere/1c.html Getting to Know the Cryosphere] {{Webarchive|url=https://web.archive.org/web/20191215212026/https://serc.carleton.edu/eslabs/cryosphere/1c.html |date=15 December 2019 }}, Earth Labs There has been an extensive loss of snow on land since 1981. Some of the largest declines have been observed in the spring.{{Cite journal |last1=Thackeray |first1=Chad W. |last2=Derksen |first2=Chris |last3=Fletcher |first3=Christopher G. |last4=Hall |first4=Alex |date=2019-12-01 |title=Snow and Climate: Feedbacks, Drivers, and Indices of Change |url=https://doi.org/10.1007/s40641-019-00143-w |journal=Current Climate Change Reports |language=en |volume=5 |issue=4 |pages=322–333 |doi=10.1007/s40641-019-00143-w |bibcode=2019CCCR....5..322T |s2cid=201675060 |issn=2198-6061}} During the 21st century, snow cover is projected to continue its retreat in almost all regions.IPCC, 2019: [https://www.ipcc.ch/site/assets/uploads/sites/3/2022/03/02_SROCC_TS_FINAL.pdf Technical Summary] [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, E. Poloczanska, K. Mintenbeck, M. Tignor, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. In: [https://www.ipcc.ch/srocc/ IPCC Special Report on the Ocean and Cryosphere in a Changing Climate] [H.- O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 39–69. {{doi|10.1017/9781009157964.002}}{{rp|39–69}}

{{Further|Retreat of glaciers since 1850}}

Since the beginning of the twentieth century, there has been a widespread retreat of glaciers.{{rp|1215}} Those glaciers that are not associated with the polar ice sheets lost around 8% of their mass between 1971 and 2019.{{rp|1275}} In the Andes in South America and in the Himalayas in Asia, the retreat of glaciers could impact water supply.{{Cite journal |last1=Lee |first1=Ethan |last2=Carrivick |first2=Jonathan L. |last3=Quincey |first3=Duncan J. |last4=Cook |first4=Simon J. |last5=James |first5=William H. M. |last6=Brown |first6=Lee E. |date=2021-12-20 |title=Accelerated mass loss of Himalayan glaciers since the Little Ice Age |journal=Scientific Reports |language=en |volume=11 |issue=1 |pages=24284 |bibcode=2021NatSR..1124284L |doi=10.1038/s41598-021-03805-8 |issn=2045-2322 |pmc=8688493 |pmid=34931039}}{{Cite book |url=https://www.worldcat.org/oclc/1085575303 |title=The Andean glacier and water atlas : the impact of glacier retreat on water resources |date=2018 |others=Tina Schoolmeester, Koen Verbist, Kari Synnøve Johansen |isbn=978-92-3-100286-1 |location=Paris, France |pages=9 |oclc=1085575303}} The melting of those glaciers could also cause landslides or glacial lake outburst floods.{{Cite web |title=As Himalayan Glaciers Melt, a Water Crisis Looms in South Asia |url=https://e360.yale.edu/features/himalayas-glaciers-climate-change |access-date=2023-05-01 |website=Yale E360 |language=en-US}}

{{Further|Antarctic ice sheet#Changes due to climate change|Greenland ice sheet#Recent melting}}

The melting of the Greenland and West Antarctic ice sheets will continue to contribute to sea level rise over long time-scales. The Greenland ice sheet loss is mainly driven by melt from the top. Antarctic ice loss is driven by warm ocean water melting the outlet glaciers.{{rp|1215}}

Future melt of the West Antarctic ice sheet is potentially abrupt under a high emission scenario, as a consequence of a partial collapse.Collins M., M. Sutherland, L. Bouwer, S.-M. Cheong, T. Frölicher, H. Jacot Des Combes, M. Koll Roxy, I. Losada, K. McInnes, B. Ratter, E. Rivera-Arriaga, R.D. Susanto, D. Swingedouw, and L. Tibig, 2019: [https://www.ipcc.ch/site/assets/uploads/sites/3/2022/03/08_SROCC_Ch06_FINAL.pdf Chapter 6: Extremes, Abrupt Changes and Managing Risk]. In: [https://www.ipcc.ch/srocc/ IPCC Special Report on the Ocean and Cryosphere in a Changing Climate] [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 589–655. {{doi|10.1017/9781009157964.008}}.{{rp|595–596}} Part of the ice sheet is grounded on bedrock below sea level. This makes it possibly vulnerable to the self-enhancing process of marine ice sheet instability. Marine ice cliff instability could also contribute to a partial collapse. But there is limited evidence for its importance.{{rp|1269–1270}} A partial collapse of the ice sheet would lead to rapid sea level rise and a local decrease in ocean salinity. It would be irreversible for decades and possibly even millennia.{{rp|595–596}} The complete loss of the West Antarctic ice sheet would cause over {{Convert|5|m}} of sea level rise.{{Cite journal |last1=Stokes |first1=Chris R. |last2=Abram |first2=Nerilie J. |last3=Bentley |first3=Michael J. |display-authors=etal |date=August 2022 |title=Response of the East Antarctic Ice Sheet to past and future climate change |url=https://www.nature.com/articles/s41586-022-04946-0 |journal=Nature |language=en |volume=608 |issue=7922 |pages=275–286 |doi=10.1038/s41586-022-04946-0 |pmid=35948707 |bibcode=2022Natur.608..275S |s2cid=251494636 |issn=1476-4687|hdl=20.500.11820/9fe0943d-ae69-4916-a57f-13965f5f2691 |hdl-access=free }}

In contrast to the West Antarctic ice sheet, melt of the Greenland ice sheet is projected to take place more gradually over millennia.{{rp|595–596}} Sustained warming between {{Convert|1|C-change}} (low confidence) and {{Convert|4|C-change}} (medium confidence) would lead to a complete loss of the ice sheet. This would contribute {{Convert|7|m|abbr=on}} to sea levels globally.{{rp|363}} The ice loss could become irreversible due to a further self-enhancing feedback. This is called the elevation-surface mass balance feedback. When ice melts on top of the ice sheet, the elevation drops. Air temperature is higher at lower altitudes, so this promotes further melting.{{rp|362}}

{{Further|Arctic sea ice decline|Antarctic sea ice#Recent trends and climate change}}

File:1978- Antarctic sea ice extent - Purich and Doddridge.png

Sea ice reflects 50% to 70% of the incoming solar radiation back into space. Only 6% of incoming solar energy is reflected by the ocean.{{Cite web|title=Thermodynamics: Albedo {{!}} National Snow and Ice Data Center|url=https://nsidc.org/cryosphere/seaice/processes/albedo.html|url-status=dead|archive-url=https://web.archive.org/web/20171011021602/https://nsidc.org/cryosphere/seaice/processes/albedo.html|archive-date=11 October 2017|access-date=14 October 2020|website=nsidc.org}} As the climate warms, the area covered by snow or sea ice decreases. After sea ice melts, more energy is absorbed by the ocean, so it warms up. This ice-albedo feedback is a self-reinforcing feedback of climate change.{{cite web|url=https://oceanservice.noaa.gov/facts/sea-ice-climate.html|access-date=21 April 2023|website=NOAA|title=How does sea ice affect global climate?}} Large-scale measurements of sea ice have only been possible since satellites came into use.

{{cite web

| title=Arctic Report Card 2012

| url=http://www.arctic.noaa.gov/reportcard/sea_ice.html

| publisher=NOAA

| access-date=8 May 2013 |archive-url=https://web.archive.org/web/20130217032825/http://www.arctic.noaa.gov/reportcard/sea_ice.html |archive-date=17 February 2013

}}

Sea ice in the Arctic has declined in recent decades in area and volume due to climate change. It has been melting more in summer than it refreezes in winter. The decline of sea ice in the Arctic has been accelerating during the early twenty-first century. It has a rate of decline of 4.7% per decade. It has declined over 50% since the first satellite records.{{Cite journal |last1=Huang |first1=Yiyi |last2=Dong |first2=Xiquan |last3=Bailey |first3=David A. |last4=Holland |first4=Marika M. |author-link4=Marika Holland |last5=Xi |first5=Baike |last6=DuVivier |first6=Alice K. |last7=Kay |first7=Jennifer E. |last8=Landrum |first8=Laura L. |last9=Deng |first9=Yi |date=2019-06-19 |title=Thicker Clouds and Accelerated Arctic Sea Ice Decline: The Atmosphere-Sea Ice Interactions in Spring |journal=Geophysical Research Letters |volume=46 |issue=12 |pages=6980–6989 |bibcode=2019GeoRL..46.6980H |doi=10.1029/2019gl082791 |issn=0094-8276 |s2cid=189968828 |doi-access=free |hdl=10150/634665|hdl-access=free }}{{Cite journal |last1=Senftleben |first1=Daniel |last2=Lauer |first2=Axel |last3=Karpechko |first3=Alexey |date=2020-02-15 |title=Constraining Uncertainties in CMIP5 Projections of September Arctic Sea Ice Extent with Observations |journal=Journal of Climate |volume=33 |issue=4 |pages=1487–1503 |bibcode=2020JCli...33.1487S |doi=10.1175/jcli-d-19-0075.1 |issn=0894-8755 |s2cid=210273007 |doi-access=free}}{{Cite journal |last1=Yadav |first1=Juhi |last2=Kumar |first2=Avinash |last3=Mohan |first3=Rahul |date=2020-05-21 |title=Dramatic decline of Arctic sea ice linked to global warming |url=http://dx.doi.org/10.1007/s11069-020-04064-y |journal=Natural Hazards |volume=103 |issue=2 |pages=2617–2621 |doi=10.1007/s11069-020-04064-y |bibcode=2020NatHa.103.2617Y |issn=0921-030X |s2cid=218762126}} Ice-free summers are expected to be rare at {{Convert|1.5|C-change}} degrees of warming. They are set to occur at least once every decade with a warming level of {{Convert|2|C-change}}.IPCC, 2018: [https://www.ipcc.ch/site/assets/uploads/sites/2/2022/06/SPM_version_report_LR.pdf Summary for Policymakers]. In: [https://www.ipcc.ch/sr15/ Global Warming of 1.5 °C. An IPCC Special Report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty] [Masson-Delmotte, V., P. Zhai, H.-O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T. Maycock, M. Tignor, and T. Waterfield (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 3-24. {{doi|10.1017/9781009157940.001}}.{{rp|8}} The Arctic will likely become ice-free at the end of some summers before 2050.Fox-Kemper, B., H.T. Hewitt, C. Xiao, G. Aðalgeirsdóttir, S.S. Drijfhout, T.L. Edwards, N.R. Golledge, M. Hemer, R.E. Kopp, G. Krinner, A. Mix, D. Notz, S. Nowicki, I.S. Nurhati, L. Ruiz, J.-B. Sallée, A.B.A. Slangen, and Y. Yu, 2021: [https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_Chapter09.pdf Chapter 9: Ocean, Cryosphere and Sea Level Change]. In [https://www.ipcc.ch/report/ar6/wg1/ Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [Masson-Delmotte, V., P. Zhai, A. Pirani, S.L. Connors, C. Péan, S. Berger, N. Caud, Y. Chen, L. Goldfarb, M.I. Gomis, M. Huang, K. Leitzell, E. Lonnoy, J.B.R. Matthews, T.K. Maycock, T. Waterfield, O. Yelekçi, R. Yu, and B. Zhou (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, US {{doi|10.1017/9781009157896.011}}{{rp|9}}

Sea ice extent in Antarctica varies a lot year by year. This makes it difficult to determine a trend, and record highs and record lows have been observed between 2013 and 2023. The general trend since 1979, the start of the satellite measurements, has been roughly flat. Between 2015 and 2023, there has been a decline in sea ice, but due to the high variability, this does not correspond to a significant trend.{{Cite web |date=14 March 2023 |title=Understanding climate: Antarctic sea ice extent |url=http://www.climate.gov/news-features/understanding-climate/understanding-climate-antarctic-sea-ice-extent |access-date=2023-03-26 |website=NOAA Climate.gov |language=}}

{{Further|Permafrost#Impacts of climate change|Climate change in Russia#Permafrost}}

Globally, permafrost warmed by about {{val|0.3|u=degC}} between 2007 and 2016. The extent of permafrost has been falling for decades. More decline is expected in the future.{{rp|1280}} Permafrost thaw makes the ground weaker and unstable. The thaw can seriously damage human infrastructure in permafrost areas such as railways, settlements and pipelines.{{Cite book |last1=Barry |first1=Roger Graham |title=The global cryosphere past, present and future |last2=Gan |first2=Thian-Yew |date=2021 |isbn=978-1-108-48755-9 |edition=Second revised |location=Cambridge, United Kingdom |oclc=1256406954}}{{rp|236}} Thawing soil can also release methane and {{CO2}} from decomposing microbes. This can generate a strong feedback loop to global warming.{{Cite journal|last1=Koven|first1=Charles D.|last2=Riley|first2=William J.|last3=Stern|first3=Alex|date=2012-10-01|title=Analysis of Permafrost Thermal Dynamics and Response to Climate Change in the CMIP5 Earth System Models|journal=Journal of Climate|volume=26|issue=6|pages=1877–1900|doi=10.1175/JCLI-D-12-00228.1|osti=1172703 |url=http://www.escholarship.org/uc/item/9cv093s8|doi-access=free}}{{Cite journal |last1=Armstrong McKay |first1=David I. |last2=Staal |first2=Arie |last3=Abrams |first3=Jesse F. |last4=Winkelmann |first4=Ricarda |last5=Sakschewski |first5=Boris |last6=Loriani |first6=Sina |last7=Fetzer |first7=Ingo |last8=Cornell |first8=Sarah E. |last9=Rockström |first9=Johan |last10=Lenton |first10=Timothy M. |date=2022-09-09 |title=Exceeding 1.5 °C global warming could trigger multiple climate tipping points |journal=Science |volume=377 |issue=6611 |pages=eabn7950 |doi=10.1126/science.abn7950 |pmid=36074831 |hdl=10871/131584 |s2cid=252161375 |hdl-access=free }} Some scientists believe that carbon storage in permafrost globally is approximately 1600 gigatons. This is twice the atmospheric pool.{{cite book |last1=Programme |first1=United Nations Environment |title=The Natural Fix? The Role of Ecosystems in Climate Mitigation: A UNEP Rapid Response Assessment |date=2009 |isbn=978-82-7701-057-1 |hdl=20.500.11822/7852 |pages=20, 55 |publisher=UNEP/Earthprint }}

{{Further|Effects of climate change on biomes}}

{{See also|Extinction risk from climate change}}File:Bleached coral (24577819729).jpg in Australia in 2016 after a coral bleaching event (partly caused by rising ocean temperatures and marine heatwaves).]]Recent warming has had a big effect on natural biological systems.Rosenzweig, C., G. Casassa, D.J. Karoly, A. Imeson, C. Liu, A. Menzel, S. Rawlins, T.L. Root, B. Seguin, P. Tryjanowski, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter1-1.pdf Chapter 1: Assessment of observed changes and responses in natural and managed systems]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 79-131.{{rp|81}} Species worldwide are moving poleward to colder areas. On land, species may move to higher elevations. Marine species find colder water at greater depths.{{cite journal |last1=Pecl |first1=Gretta T. |last2=Araújo |first2=Miguel B. |last3=Bell |first3=Johann D. |last4=Blanchard |first4=Julia |last5=Bonebrake |first5=Timothy C. |last6=Chen |first6=I-Ching |last7=Clark |first7=Timothy D. |last8=Colwell |first8=Robert K. |last9=Danielsen |first9=Finn |last10=Evengård |first10=Birgitta |last11=Falconi |first11=Lorena |last12=Ferrier |first12=Simon |last13=Frusher |first13=Stewart |last14=Garcia |first14=Raquel A. |last15=Griffis |first15=Roger B. |last16=Hobday |first16=Alistair J. |last17=Janion-Scheepers |first17=Charlene |last18=Jarzyna |first18=Marta A. |last19=Jennings |first19=Sarah |last20=Lenoir |first20=Jonathan |last21=Linnetved |first21=Hlif I. |last22=Martin |first22=Victoria Y. |last23=McCormack |first23=Phillipa C. |last24=McDonald |first24=Jan |last25=Mitchell |first25=Nicola J. |last26=Mustonen |first26=Tero |last27=Pandolfi |first27=John M. |last28=Pettorelli |first28=Nathalie |last29=Popova |first29=Ekaterina |last30=Robinson |first30=Sharon A. |last31=Scheffers |first31=Brett R. |last32=Shaw |first32=Justine D. |last33=Sorte |first33=Cascade J. B. |last34=Strugnell |first34=Jan M. |last35=Sunday |first35=Jennifer M. |last36=Tuanmu |first36=Mao-Ning |last37=Vergés |first37=Adriana |last38=Villanueva |first38=Cecilia |last39=Wernberg |first39=Thomas |last40=Wapstra |first40=Erik |last41=Williams |first41=Stephen E. |title=Biodiversity redistribution under climate change: Impacts on ecosystems and human well-being |journal=Science |date=31 March 2017 |volume=355 |issue=6332 |pages=eaai9214 |doi=10.1126/science.aai9214 |pmid=28360268 |s2cid=206653576 |hdl=10019.1/120851 |url=http://ecite.utas.edu.au/115569 |hdl-access=free }} Climate change had the third biggest impact on nature out of various factors in the five decades up to 2020. Only change in land use and sea use and direct exploitation of organisms had a bigger impact.{{Cite book|last=Díaz|first=S.|url=https://ipbes.net/system/tdf/inline/files/ipbes_global_assessment_report_summary_for_policymakers.pdf?file=1&type=node&id=36213|title=Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.|publisher=ISBES secretariat|year=2019|location=Bonn, Germany|page=12|display-authors=etal.|access-date=28 December 2019|archive-date=23 July 2021|archive-url=https://web.archive.org/web/20210723103208/https://ipbes.net/sites/default/files/inline/files/ipbes_global_assessment_report_summary_for_policymakers.pdf|url-status=live}}

The impacts of climate change on nature are likely to become bigger in the next few decades.{{Cite book|last=Díaz|first=S.|url=https://ipbes.net/system/tdf/inline/files/ipbes_global_assessment_report_summary_for_policymakers.pdf?file=1&type=node&id=36213|title=Summary for policymakers of the global assessment report on biodiversity and ecosystem services of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services.|publisher=ISBES secretariat|year=2019|location=Bonn, Germany|page=16|display-authors=etal.|access-date=28 December 2019|archive-date=23 July 2021|archive-url=https://web.archive.org/web/20210723103208/https://ipbes.net/sites/default/files/inline/files/ipbes_global_assessment_report_summary_for_policymakers.pdf|url-status=live}} The stresses caused by climate change, combine with other stresses on ecological systems such as land conversion, land degradation, harvesting, and pollution. They threaten substantial damage to unique ecosystems. They can even result in their complete loss and the extinction of species.{{cite journal |last1=McElwee |first1=Pamela |title=Climate Change and Biodiversity Loss |journal=Current History |date=1 November 2021 |volume=120 |issue=829 |pages=295–300 |doi=10.1525/curh.2021.120.829.295 |s2cid=240056779 |doi-access=free }}{{Cite journal |last1=Meyer |first1=Andreas L. S. |last2=Bentley |first2=Joanne |last3=Odoulami |first3=Romaric C. |last4=Pigot |first4=Alex L. |last5=Trisos |first5=Christopher H. |date=15 August 2022 |title=Risks to biodiversity from temperature overshoot pathways |journal=Philosophical Transactions of the Royal Society B: Biological Sciences |volume=377 |issue=1857 |pages=20210394 |doi=10.1098/rstb.2021.0394 |pmc=9234811 |pmid=35757884}} This can disrupt key interactions between species within ecosystems. This is because species from one location do not leave the warming habitat at the same rate. The result is rapid changes in the way the ecosystem functions. Impacts include changes in regional rainfall patterns. Another is earlier leafing of trees and plants over many regions. Movements of species to higher latitudes and altitudes,{{Cite web |last1=Wolfe |first1=Barrett |last2=Champion |first2=Curtis |last3=Pecl |first3=Gretta |last4=Strugnell |first4=Jan |last5=Watson |first5=Sue-Ann |title=Thousands of photos captured by everyday Australians reveal the secrets of our marine life as oceans warm |url=http://theconversation.com/thousands-of-photos-captured-by-everyday-australians-reveal-the-secrets-of-our-marine-life-as-oceans-warm-189231 |access-date=2023-05-09 |website=The Conversation |date=28 August 2022 |language=en}} changes in bird migrations, and shifting of the oceans' plankton and fish from cold- to warm-adapted communities are other impacts.

{{cite web

| url=http://www.giss.nasa.gov/research/briefs/rosenzweig_02/

| archive-url=https://web.archive.org/web/20090404135111/http://www.giss.nasa.gov/research/briefs/rosenzweig_02/

| url-status=dead

| archive-date=4 April 2009

| title=Science Briefs: Warming Climate is Changing Life on Global Scale

| author=Rosenzweig, C.

| date=December 2008

| publisher=Website of the US National Aeronautics and Space Administration, Goddard Institute for Space Studies

| access-date=8 July 2011

}}

These changes of land and ocean ecosystems have direct effects on human well-being.{{cite book |last1=Parmesan |first1=Camille |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Morecroft |first2=Mike |last3=Trisurat |first3=Yongyut |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=206 |chapter=Chapter 2: Terrestrial and Freshwater Ecosystems and their Services |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter02.pdf}}Cooley, S., D. Schoeman, L. Bopp, P. Boyd, S. Donner, D.Y. Ghebrehiwet, S.-I. Ito, W. Kiessling, P. Martinetto, E. Ojea, M.-F. Racault, B. Rost, and M. Skern-Mauritzen, 2022: [https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter03.pdf Chapter 3: Oceans and Coastal Ecosystems and Their Services]. In: [https://www.ipcc.ch/report/ar6/wg2/ Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 379–550, doi:10.1017/9781009325844.005.{{rp|385}} For instance, ocean ecosystems help with coastal protection and provide food.{{rp|385}} Freshwater and land ecosystems can provide water for human consumption. Furthermore, these ecosystems can store carbon. This helps to stabilize the climate system.

{{Further|Effects of climate change on plant biodiversity}}

Climate change is a major driver of biodiversity loss in different land types. These include cool conifer forests, savannas, mediterranean-climate systems, tropical forests, and the Arctic tundra.Fischlin, A., G.F. Midgley, J.T. Price, R. Leemans, B. Gopal, C. Turley, M.D.A. Rounsevell, O.P. Dube, J. Tarazona, A.A. Velichko, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter4-1.pdf Chapter 4: Ecosystems, their properties, goods, and services]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, 211-272.{{rp|239}} In other ecosystems, land-use change may be a stronger driver of biodiversity loss, at least in the near term.{{rp|239}} Beyond 2050, climate change may be the major cause of biodiversity loss globally.{{rp|239}} Climate change interacts with other pressures. These include habitat modification, pollution and invasive species. Through this interaction, climate change increases the risk of extinction for many terrestrial and freshwater species.{{Cite book|last1=Settele|first1=J.|title={{Harvnb|IPCC AR5 WG2 A|2014}}|last2=Scholes|first2=R.|last3=Betts|first3=R.|last4=Bunn|first4=S.|last5=Leadley|first5=P.|last6=Nepstad|first6=D.|last7=Overpeck|first7=J. T.|last8=Taboada|first8=M. A.|year=2014|page=275|chapter=Chapter 4: Terrestrial and Inland Water Systems|ref={{harvid|IPCC AR5 WG2 Ch4|2014}}|display-authors=4|chapter-url=https://archive.ipcc.ch/pdf/assessment-report/ar5/wg2/WGIIAR5-Chap4_FINAL.pdf|access-date=2 January 2020|archive-date=19 December 2019|archive-url=https://web.archive.org/web/20191219013722/https://archive.ipcc.ch/pdf/assessment-report/ar5/wg2/WGIIAR5-Chap4_FINAL.pdf|url-status=live}} At {{Convert|1.2|C-change}} of warming (around 2023{{Cite web |last=Cuff |first=Madeleine |title=The first breach of 1.5 °C will be a temporary but devastating failure |url=https://www.newscientist.com/article/2354824-the-first-breach-of-1-5c-will-be-a-temporary-but-devastating-failure/ |access-date=2023-05-09 |website=New Scientist |language=en-US}}) some ecosystems are threatened by mass die-offs of trees and from heatwaves.{{Cite web |title=Fact sheet - Biodiversity |url=https://www.ipcc.ch/report/ar6/wg2/downloads/outreach/IPCC_AR6_WGII_FactSheet_Biodiversity.pdf |website=IPCC Sixth Assessment Report}} At {{Convert|2|C-change}} of warming, around 10% of species on land would become critically endangered. This differs by group. For instance insects and salamanders are more vulnerable.{{rp|259}}[[File:20210331 Global tree cover loss - World Resources Institute.svg|thumb| upright=1.35 |The rate of global tree cover loss has approximately doubled since 2001, to an annual loss approaching an area the size of Italy.{{cite news |ref={{harvid|World Resources Institute, 31 March|2021}}

|last1=Butler |first1=Rhett A.

|title=Global forest loss increases in 2020

|url=https://news.mongabay.com/2021/03/global-forest-loss-increases-in-2020-but-pandemics-impact-unclear/

|work=Mongabay

|date=31 March 2021

|archive-url=https://web.archive.org/web/20210401022404/https://news.mongabay.com/2021/03/global-forest-loss-increases-in-2020-but-pandemics-impact-unclear/

|archive-date=1 April 2021

|url-status=live }} ● Data from {{cite web |title=Indicators of Forest Extent / Forest Loss |url=https://research.wri.org/gfr/forest-extent-indicators/forest-loss |publisher=World Resources Institute |archive-url=https://web.archive.org/web/20240527180607/https://research.wri.org/gfr/forest-extent-indicators/forest-loss |archive-date=27 May 2024 |date=4 April 2024 |url-status=live }} Chart in section titled "Annual rates of global tree cover loss have risen since 2000".]]

Rainfall on the Amazon rainforest is recycled when it evaporates back into the atmosphere instead of running off away from the rainforest. This water is essential for sustaining the rainforest. Due to deforestation the rainforest is losing this ability. This effect is even worse because climate change brings more frequent droughts to the area. The higher frequency of droughts in the first two decades of the 21st century and other data signal that a tipping point from rainforest to savanna might be close. A 2019 study concluded that this ecosystem could begin a 50-year-long collapse to a savanna around 2021. After that it would become increasingly and disproportionally more difficult to prevent or reverse this shift.{{cite journal |last1=Lovejoy |first1=Thomas E. |last2=Nobre |first2=Carlos |year=2019 |title=Amazon tipping point: Last chance for action |journal=Science Advances |volume=5 |issue=12 |page=eaba2949 |bibcode=2019SciA....5A2949L |doi=10.1126/sciadv.aba2949 |pmc=6989302 |pmid=32064324 |doi-access=free}}{{cite web |date=10 March 2020 |title=Ecosystems the size of Amazon 'can collapse within decades' |url=https://www.theguardian.com/environment/2020/mar/10/ecosystems-size-of-amazon-rainforest-can-collapse-within-decades |url-status=live |archive-url=https://web.archive.org/web/20200412143545/https://www.theguardian.com/environment/2020/mar/10/ecosystems-size-of-amazon-rainforest-can-collapse-within-decades |archive-date=12 April 2020 |access-date=13 April 2020 |website=The Guardian }}{{cite journal |last1=Cooper |first1=Gregory S. |last2=Willcock |first2=Simon |last3=Dearing |first3=John A. |date=10 March 2020 |title=Regime shifts occur disproportionately faster in larger ecosystems |journal=Nature Communications |volume=11 |issue=1 |pages=1175 |bibcode=2020NatCo..11.1175C |doi=10.1038/s41467-020-15029-x |pmc=7064493 |pmid=32157098 }}

{{Main|Effects of climate change on oceans#Impacts on marine life|Ocean acidification|Ocean deoxygenation}}

File:Climate_change_threats_to_coral_reefs.png ecosystems, through sea level rise, changes to the frequency and intensity of tropical storms, and altered ocean circulation patterns. When combined, all of these impacts dramatically alter ecosystem function, as well as the goods and services coral reef ecosystems provide.{{Cite web |last=US Department of Commerce |first=National Oceanic and Atmospheric Administration |title=How does climate change affect coral reefs? |url=https://oceanservice.noaa.gov/facts/coralreef-climate.html |access-date=2024-02-19 |website=oceanservice.noaa.gov |language=EN-US}}]]

Marine heatwaves are happening more often. They have widespread impacts on life in the oceans. These include mass dying events and coral bleaching.{{cite journal |last1=Smale |first1=Dan A. |last2=Wernberg |first2=Thomas |last3=Oliver |first3=Eric C. J. |last4=Thomsen |first4=Mads |last5=Harvey |first5=Ben P. |last6=Straub |first6=Sandra C. |last7=Burrows |first7=Michael T. |last8=Alexander |first8=Lisa V. |last9=Benthuysen |first9=Jessica A. |last10=Donat |first10=Markus G. |last11=Feng |first11=Ming |last12=Hobday |first12=Alistair J. |last13=Holbrook |first13=Neil J. |last14=Perkins-Kirkpatrick |first14=Sarah E. |last15=Scannell |first15=Hillary A. |last16=Sen Gupta |first16=Alex |last17=Payne |first17=Ben L. |last18=Moore |first18=Pippa J. |title=Marine heatwaves threaten global biodiversity and the provision of ecosystem services |journal=Nature Climate Change |date=April 2019 |volume=9 |issue=4 |pages=306–312 |doi=10.1038/s41558-019-0412-1 |bibcode=2019NatCC...9..306S |s2cid=91471054 |url=https://api.research-repository.uwa.edu.au/ws/files/69272031/AAM_marine_heatwaves_threaten.pdf }} Harmful algae blooms have increased. This is in response to warming waters, loss of oxygen and eutrophication.Bindoff, N.L., W.W.L. Cheung, J.G. Kairo, J. Arístegui, V.A. Guinder, R. Hallberg, N. Hilmi, N. Jiao, M.S. Karim, L. Levin, S. O'Donoghue, S.R. Purca Cuicapusa, B. Rinkevich, T. Suga, A. Tagliabue, and P. Williamson, 2019: [https://www.ipcc.ch/site/assets/uploads/sites/3/2022/03/07_SROCC_Ch05_FINAL.pdf Chapter 5: Changing Ocean, Marine Ecosystems, and Dependent Communities]. In: [https://www.ipcc.ch/srocc/ IPCC Special Report on the Ocean and Cryosphere in a Changing Climate] [H.-O. Pörtner, D.C. Roberts, V. Masson-Delmotte, P. Zhai, M. Tignor, E. Poloczanska, K. Mintenbeck, A. Alegría, M. Nicolai, A. Okem, J. Petzold, B. Rama, N.M. Weyer (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 447–587. {{doi|10.1017/9781009157964.007}}.{{rp|451}} Melting sea ice destroys habitat, including for algae that grows on its underside.{{Cite journal |last1=Riebesell |first1=Ulf |last2=Körtzinger |first2=Arne |last3=Oschlies |first3=Andreas |date=2009 |title=Sensitivities of marine carbon fluxes to ocean change |journal=PNAS |volume=106 |issue=49 |pages=20602–20609 |doi=10.1073/pnas.0813291106 |pmc=2791567 |pmid=19995981 |doi-access=free}}

Ocean acidification can harm marine organisms in various ways. Shell-forming organisms like oysters are particularly vulnerable. Some phytoplankton and seagrass species may benefit. However, some of these are toxic to fish phytoplankton species. Their spread poses risks to fisheries and aquaculture. Fighting pollution can reduce the impact of acidification.{{Cite journal |last1=Hall-Spencer |first1=Jason M. |last2=Harvey |first2=Ben P. |date=2019-05-10 |editor-last=Osborn |editor-first=Dan |title=Ocean acidification impacts on coastal ecosystem services due to habitat degradation |url=https://portlandpress.com/emergtoplifesci/article/3/2/197/219721/Ocean-acidification-impacts-on-coastal-ecosystem |journal=Emerging Topics in Life Sciences |language=en |volume=3 |issue=2 |pages=197–206 |doi=10.1042/ETLS20180117 |issn=2397-8554 |pmc=7289009 |pmid=33523154}}

Warm-water coral reefs are very sensitive to global warming and ocean acidification. Coral reefs provide a habitat for thousands of species. They provide ecosystem services such as coastal protection and food. But 70–90% of today's warm-water coral reefs will disappear even if warming is kept to {{Convert|1.5|C-change}}.Hoegh-Guldberg, O., D. Jacob, M. Taylor, M. Bindi, S. Brown, I. Camilloni, A. Diedhiou, R. Djalante, K.L. Ebi, F. Engelbrecht, J.Guiot, Y. Hijioka, S. Mehrotra, A. Payne, S.I. Seneviratne, A. Thomas, R. Warren, and G. Zhou, 2018: [https://www.ipcc.ch/site/assets/uploads/sites/2/2022/06/SR15_Chapter_3_LR.pdf Chapter 3: Impacts of 1.5 °C Global Warming on Natural and Human Systems]. In: [https://www.ipcc.ch/sr15/ Global Warming of 1.5 °C. An IPCC Special Report on the impacts of global warming of 1.5 °C above pre-industrial levels and related global greenhouse gas emission pathways, in the context of strengthening the global response to the threat of climate change, sustainable development, and efforts to eradicate poverty] [Masson-Delmotte, V., P. Zhai, H.-O. Pörtner, D. Roberts, J. Skea, P.R. Shukla, A. Pirani, W. Moufouma-Okia, C. Péan, R. Pidcock, S. Connors, J.B.R. Matthews, Y. Chen, X. Zhou, M.I. Gomis, E. Lonnoy, T.Maycock, M.Tignor, and T. Waterfield (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, USA, pp. 175-312. {{doi|10.1017/9781009157940.005}}.{{rp|179}} Coral reefs are framework organisms. They build physical structures that form habitats for other sea creatures. Other framework organisms are also at risk from climate change. Mangroves and seagrass are considered to be at moderate risk from lower levels of global warming.{{rp|225}}

{{Main|Tipping points in the climate system|Abrupt climate change}}

File:Tipping_points_2022_list.jpeg |access-date=31 January 2024 }}{{Cite journal |last1=Armstrong McKay |first1=David I. |last2=Staal |first2=Arie |last3=Abrams |first3=Jesse F. |last4=Winkelmann |first4=Ricarda |last5=Sakschewski |first5=Boris |last6=Loriani |first6=Sina |last7=Fetzer |first7=Ingo |last8=Cornell |first8=Sarah E. |last9=Rockström |first9=Johan |last10=Lenton |first10=Timothy M. |date=2022 |title=Exceeding 1.5°C global warming could trigger multiple climate tipping points |url=https://www.science.org/doi/10.1126/science.abn7950 |journal=Science |language=en |volume=377 |issue=6611 |pages=eabn7950 |doi=10.1126/science.abn7950 |pmid=36074831 |issn=0036-8075|hdl=10871/131584 |hdl-access=free }}]]

The climate system exhibits "threshold behavior" or tipping points when parts of the natural environment enter into a new state. Examples are the runaway loss of ice sheets or the dieback of forests.{{cite news|title=Climate emergency: world 'may have crossed tipping points'|newspaper=The Guardian|url=https://www.theguardian.com/environment/2019/nov/27/climate-emergency-world-may-have-crossed-tipping-points|last=Carrington|first=Damian|date=27 November 2019|access-date=4 January 2020|archive-date=4 January 2020|archive-url=https://web.archive.org/web/20200104180138/https://www.theguardian.com/environment/2019/nov/27/climate-emergency-world-may-have-crossed-tipping-points|url-status=live}} Tipping behavior is found in all parts of the climate system. These include ecosystems, ice sheets, and the circulation of the ocean and atmosphere.{{Cite web |last=Leahy |first=Stephen |date=2019-11-27 |title=Climate change driving entire planet to dangerous 'global tipping point' |url=https://www.nationalgeographic.com/science/article/earth-tipping-point |archive-url=https://web.archive.org/web/20210219175124/https://www.nationalgeographic.com/science/article/earth-tipping-point |url-status=dead |archive-date=19 February 2021 |access-date=2023-05-06 |website=National Geographic |language=en}} Tipping points are studied using data from Earth's distant past and by physical modeling.Kopp, R.E., K. Hayhoe, D.R. Easterling, T. Hall, R. Horton, K.E. Kunkel, and A.N. LeGrande, [https://science2017.globalchange.gov/chapter/15/ 2017: Potential surprises – compound extremes and tipping elements]. In: [https://science2017.globalchange.gov/ Climate Science Special Report: Fourth National Climate Assessment, Volume I] [Wuebbles, D.J., D.W. Fahey, K.A. Hibbard, D.J. Dokken, B.C. Stewart, and T.K. Maycock (eds.)]. U.S. Global Change Research Program, Washington, DC, USA, pp. 411-429, doi: 10.7930/J0GB227J There is already moderate risk of global tipping points at {{Convert|1|C-change}} above pre-industrial temperatures. That becomes a high risk at {{Convert|2.5|C-change}}.{{rp|254, 258}} It is possible that some tipping points are close or have already been crossed. Examples are the West Antarctic and Greenland ice sheets, the Amazon rainforest, and warm-water coral reefs.{{Cite journal |last1=Ripple |first1=William J |last2=Wolf |first2=Christopher |last3=Newsome |first3=Thomas M. |last4=Gregg |first4=Jillian W. |last5=Lenton |first5=Tim |author5-link=Tim Lenton |last6=Palomo |first6=Ignacio |last7=Eikelboom |first7=Jasper A. J. |last8=Law |first8=Beverly E. |last9=Huq |first9=Saleemul |last10=Duffy |first10=Philip B. |last11=Rockström |first11=Johan |date=28 July 2021 |title=World Scientists' Warning of a Climate Emergency 2021 |url=https://doi.org/10.1093/biosci/biab079 |journal=BioScience |volume=71 |issue=biab079 |pages=894–898 |doi=10.1093/biosci/biab079 |issn=0006-3568 |hdl-access=free |hdl=1808/30278}}

Tipping points are perhaps the most dangerous aspect of future climate change, potentially leading to irreversible impacts on society.{{cite journal |last1=Lontzek |first1=Thomas S. |last2=Cai |first2=Yongyang |last3=Judd |first3=Kenneth L. |last4=Lenton |first4=Timothy M. |title=Stochastic integrated assessment of climate tipping points indicates the need for strict climate policy |journal=Nature Climate Change |date=May 2015 |volume=5 |issue=5 |pages=441–444 |doi=10.1038/nclimate2570 |bibcode=2015NatCC...5..441L |hdl=10871/35041 |s2cid=84760180 |hdl-access=free }} A collapse of the Atlantic meridional overturning circulation would likely halve rainfall in India and lead to severe drops in temperature in Northern Europe.{{Cite book |url=https://www.oecd-ilibrary.org/docserver/abc5a69e-en.pdf?expires=1683357411&id=id&accname=guest&checksum=793F81B2D97F534B5300C730F4C6EF59 |title=Climate Tipping Points: Insights for Effective Policy Action |vauthors=OECD |publisher=OECD Publishing |year=2022 |isbn=978-92-64-35465-4 |location=Paris |pages=29}} Many tipping points are interlinked such that triggering one may lead to a cascade of effects.{{Cite journal|last1=Lenton|first1=Timothy M.|last2=Rockström|first2=Johan|last3=Gaffney|first3=Owen|last4=Rahmstorf|first4=Stefan|last5=Richardson|first5=Katherine|last6=Steffen|first6=Will|last7=Schellnhuber|first7=Hans Joachim|date=2019|title=Climate tipping points — too risky to bet against|journal=Nature|volume=575|issue=7784|pages=592–595|doi=10.1038/d41586-019-03595-0|doi-access=free|pmid=31776487|bibcode=2019Natur.575..592L|hdl=10871/40141|hdl-access=free}} This remains a possibility even well below {{Convert|2|C-change}} of warming.{{cite news |last1=Carrington |first1=Damian |title=Climate tipping points could topple like dominoes, warn scientists |url=https://www.theguardian.com/environment/2021/jun/03/climate-tipping-points-could-topple-like-dominoes-warn-scientists |access-date=8 June 2021 |work=The Guardian |date=3 June 2021 |archive-date=7 June 2021 |archive-url=https://web.archive.org/web/20210607185015/https://www.theguardian.com/environment/2021/jun/03/climate-tipping-points-could-topple-like-dominoes-warn-scientists |url-status=live }} A 2018 study states that 45% of environmental problems, including those caused by climate change, are interconnected. This increases the risk of a domino effect.{{cite journal |last1=C. Rocha |first1=Juan |last2=Peterson |first2=Garry |last3=Bodin |first3=Örjan |last4=Levin |first4=Simon |title=Cascading regime shifts within and across scales |journal=Science |date=21 December 2018 |volume=362 |issue=6421 |pages=1379–1383 |bibcode=2018Sci...362.1379R |doi=10.1126/science.aat7850 |pmid=30573623 |s2cid=56582186 |doi-access=free }}{{cite news |last1=Watts |first1=Jonathan |title=Risks of 'domino effect' of tipping points greater than thought, study says |url=https://www.theguardian.com/environment/2018/dec/20/risks-of-domino-effect-of-tipping-points-greater-than-thought-study-says?CMP=greenlight_email |access-date=24 December 2018 |work=The Guardian |date=20 December 2018 |archive-date=7 February 2019 |archive-url=https://web.archive.org/web/20190207141140/https://www.theguardian.com/environment/2018/dec/20/risks-of-domino-effect-of-tipping-points-greater-than-thought-study-says?CMP=greenlight_email |url-status=live }}

Further impacts may be irreversible, at least over the timescale of many human generations.Schneider, S.H., S. Semenov, A. Patwardhan, I. Burton, C.H.D. Magadza, M. Oppenheimer, A.B. Pittock, A. Rahman, J.B. Smith, A. Suarez and F. Yamin, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter19-1.pdf Chapter 19: Assessing key vulnerabilities and the risk from climate change]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 779-810{{rp|785}} This includes warming of the deep ocean and acidification. These are set to continue even when global temperatures stop rising.{{Cite book |last1=Arias |first1=Paola A. |title=Climate Change 2021: The Physical Science Basis. Contribution of Working Group I to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |last2=Bellouin |first2=Nicolas |last3=Coppola |first3=Erika |last4=Jones |first4=Richard G. |year=2021 |pages=106 |chapter=Technical Summary |display-authors=etal |chapter-url=https://www.ipcc.ch/report/ar6/wg1/downloads/report/IPCC_AR6_WGI_TS.pdf}} In biological systems, the extinction of species would be an irreversible impact.{{rp|785}} In social systems, unique cultures may be lost.{{rp|785}} Climate change could make it more likely that endangered languages disappear.{{cite journal |last1=Sabūnas |first1=Audrius |last2=Miyashita |first2=Takuya |last3=Fukui |first3=Nobuki |last4=Shimura |first4=Tomoya |last5=Mori |first5=Nobuhito |title=Impact Assessment of Storm Surge and Climate Change-Enhanced Sea Level Rise on Atoll Nations: A Case Study of the Tarawa Atoll, Kiribati |journal=Frontiers in Built Environment |doi=10.3389/fbuil.2021.752599|date=10 November 2021|volume=7 |doi-access=free }}

Humans have a climate niche. This is a certain range of temperatures in which they flourish. Outside that niche, conditions are less favourable. This leads to negative effects on health, food security and more. This niche is a mean annual temperature below 29 °C. As of May 2023, 60 million people lived outside this niche. With every additional 0.1 degree of warming, 140 million people will be pushed out of it.{{cite news |last1=Carrington |first1=Damian |title=Global heating will push billions outside 'human climate niche' |url=https://www.theguardian.com/environment/2023/may/22/global-heating-human-climate-niche |access-date=1 June 2023 |agency=The Guardian |date=22 May 2023}}

{{excerpt|Effects of climate change on human health|paragraphs=1–3|file=no}}

{{excerpt|Effects of climate change on mental health|paragraphs=1–2|file=no}}

{{Main|Effects of climate change on agriculture#Global food security and undernutrition|Climate change and fisheries|Effects of climate change on livestock}}

File:Hasegawa_2016_hunger_DALYs.png), population at risk of hunger and disability-adjusted life years under two Shared Socioeconomic Pathways: the baseline, SSP2, and SSP3, scenario of high global rivalry and conflict. The red and the orange lines show projections for SSP3 assuming high and low intensity of future emissions and the associated climate change.{{cite journal |last1=Hasegawa |first1=Tomoko |last2=Fujimori |first2=Shinichiro |last3=Takahashi |first3=Kiyoshi |last4=Yokohata |first4=Tokuta |last5=Masui |first5=Toshihiko |date=29 January 2016 |title=Economic implications of climate change impacts on human health through undernourishment |journal=Climatic Change |volume=136 |issue=2 |pages=189–202 |doi=10.1007/s10584-016-1606-4|doi-access=free |bibcode=2016ClCh..136..189H }}]]

Climate change will affect agriculture and food production around the world. The reasons include the effects of elevated CO₂ in the atmosphere. Higher temperatures and altered precipitation and transpiration regimes are also factors. Increased frequency of extreme events and modified weed, pest, and pathogen pressure are other factors.Easterling, W.E., P.K. Aggarwal, P. Batima, K.M. Brander, L. Erda, S.M. Howden, A. Kirilenko, J. Morton, J.-F. Soussana, J. Schmidhuber and F.N. Tubiello, 2007: [https://www.ipcc.ch/site/assets/uploads/2018/02/ar4-wg2-chapter5-1.pdf Chapter 5: Food, fibre and forest products]. [https://www.ipcc.ch/report/ar4/wg2/ Climate Change 2007: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change], M.L. Parry, O.F. Canziani, J.P. Palutikof, P.J. van der Linden and C.E. Hanson, Eds., Cambridge University Press, Cambridge, UK, 273-313.{{rp|282}} Droughts result in crop failures and the loss of pasture for livestock.{{cite journal |last1=Ding |first1=Ya |last2=Hayes |first2=Michael J. |last3=Widhalm |first3=Melissa |title=Measuring economic impacts of drought: a review and discussion |journal=Disaster Prevention and Management |date=30 August 2011 |volume=20 |issue=4 |pages=434–446 |doi=10.1108/09653561111161752 |bibcode=2011DisPM..20..434D |url=http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1198&context=natrespapers }} Loss and poor growth of livestock cause milk yield and meat production to decrease.{{cite journal |last1=Ndiritu |first1=S. Wagura |last2=Muricho |first2=Geoffrey |date=2021 |title=Impact of climate change adaptation on food security: evidence from semi-arid lands, Kenya |url=https://www.researchsquare.com/article/rs-174615/v1.pdf?c=1631867581000 |journal=Climatic Change |volume=167 |issue=1–2 |pages=24 |bibcode=2021ClCh..167...24N |doi=10.1007/s10584-021-03180-3 |s2cid=233890082}} The rate of soil erosion is 10–20 times higher than the rate of soil accumulation in agricultural areas that use no-till farming. In areas with tilling it is 100 times higher. Climate change worsens this type of land degradation and desertification.{{rp|5}}

Climate change is projected to negatively affect all four pillars of food security. It will affect how much food is available. It will also affect how easy food is to access through prices, food quality, and how stable the food system is.{{Cite book |last1=Mbow |first1=C. |url=https://www.ipcc.ch/srccl/ |title=IPCC Special Report on climate change, desertification, land degradation, sustainable land management, food security, and greenhouse gas fluxes in terrestrial ecosystems |last2=Rosenzweig |first2=C. |last3=Barioni |first3=L. G. |last4=Benton |first4=T. |last5=Herrero |first5=M. |last6=Krishnapillai |first6=M. V. |last7=Liwenga |first7=E. |last8=Pradhan |first8=P. |last9=Rivera-Ferre |first9=M. G. |year=2019 |page=442 |chapter=Chapter 5: Food Security |display-authors=4 |access-date=24 December 2019 |chapter-url=https://www.ipcc.ch/site/assets/uploads/2019/08/2f.-Chapter-5_FINAL.pdf |archive-url=https://web.archive.org/web/20191127221442/https://www.ipcc.ch/site/assets/uploads/2019/08/2f.-Chapter-5_FINAL.pdf |archive-date=27 November 2019 |url-status=live |first12=Y. |last15=Challinor |first10=T. |last16=Porter |first15=A. J. |last11=Tubiello |first16=J. R. |last12=Xu |first13=A. |first14=N. |last14=Benkeblia |first11=F. N. |last10=Sapkota |last13=Amanullah}} Climate change is already affecting the productivity of wheat and other staples.{{cite journal |last1=Vermeulen |first1=Sonja J. |last2=Campbell |first2=Bruce M. |last3=Ingram |first3=John S.I. |title=Climate Change and Food Systems |journal=Annual Review of Environment and Resources |date=21 November 2012 |volume=37 |issue=1 |pages=195–222 |doi=10.1146/annurev-environ-020411-130608 |s2cid=28974132 |doi-access=free }}{{cite journal |last1=Carter |first1=Colin |last2=Cui |first2=Xiaomeng |last3=Ghanem |first3=Dalia |last4=Mérel |first4=Pierre |title=Identifying the Economic Impacts of Climate Change on Agriculture |journal=Annual Review of Resource Economics |date=5 October 2018 |volume=10 |issue=1 |pages=361–380 |doi=10.1146/annurev-resource-100517-022938 |s2cid=158817046 |url=https://escholarship.org/uc/item/50t4t5j9 }}

In many areas, fishery catches are already decreasing because of global warming and changes in biochemical cycles. In combination with overfishing, warming waters decrease the amount of fish in the ocean.{{rp|12}} Per degree of warming, ocean biomass is expected to decrease by about 5%. Tropical and subtropical oceans are most affected, while there may be more fish in polar waters.{{cite book |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter05.pdf |chapter=Chapter 5: Food, Fibre, and other Ecosystem Products |last1= Bezner Kerr |first1=Rachel |last2=Hasegawa |first2=Toshihiro |last3=Lasco |first3=Rodel |last4=Bhatt |first4=Indra | publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |display-authors=etal| title=Climate Change 2022: Impacts, Adaptation and Vulnerability| page=766}}

{{Further|Water security#Climate change}}

Water resources can be affected by climate change in various ways. The total amount of freshwater available can change, for instance due to dry spells or droughts. Heavy rainfall and flooding can have an impact on water quality. They can transport pollutants into water bodies through increased surface runoff. In coastal regions, more salt may find its way into water resources due to higher sea levels and more intense storms. Higher temperatures also directly degrade water quality. This is because warm water contains less oxygen. Changes in the water cycle threaten existing and future water infrastructure. It will be harder to plan investments for water infrastructure. This is because there are significant uncertainties about future variability of the water cycle.{{cite book |last1=Sadoff |first1=Claudia |title=Oxford Research Encyclopedia of Environmental Science |last2=Grey |first2=David |last3=Borgomeo |first3=Edoardo |year=2020 |isbn=978-0-19-938941-4 |chapter=Water Security |doi=10.1093/acrefore/9780199389414.013.609}}

Between 1.5 and 2.5 billion people live in areas with regular water security issues. If global warming reaches {{Convert|4|C-change}}, water insecurity would affect about twice as many people.{{cite book |last1=Caretta |first1=Martina Angela |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Mukherji |first2=Aditi |publisher=Intergovernmental Panel on Climate Change |series=Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |at=FAQ4.1 |chapter=Chapter 4: Water |display-authors=etal |chapter-url=https://report.ipcc.ch/ar6wg2/pdf/IPCC_AR6_WGII_FinalDraft_Chapter04.pdf |access-date=12 March 2022 |archive-date=25 June 2022 |archive-url=https://web.archive.org/web/20220625205812/https://report.ipcc.ch/ar6wg2/pdf/IPCC_AR6_WGII_FinalDraft_Chapter04.pdf |url-status=dead }} Water resources are likely to decrease in most dry subtropical regions and mid-latitudes. But they will increase in high latitudes. However, variable streamflow means even regions with increased water resources can experience additional short-term shortages.Jiménez Cisneros, B.E., T. Oki, N.W. Arnell, G. Benito, J.G. Cogley, P. Döll, T. Jiang, and S.S. Mwakalila, 2014: [https://archive.ipcc.ch/pdf/assessment-report/ar5/wg2/WGIIAR5-Chap3_FINAL.pdf Chapter 3: Freshwater resources]. In: [https://www.ipcc.ch/report/ar5/wg2/ Climate Change 2014: Impacts,Adaptation, and Vulnerability. Part A: Global and Sectoral Aspects. Contribution of Working Group II to the Fifth Assessment Report of the Intergovernmental Panel on Climate Change] [Field, C.B., V.R. Barros, D.J. Dokken, K.J. Mach, M.D. Mastrandrea, T.E. Bilir, M. Chatterjee, K.L. Ebi, Y.O. Estrada, R.C. Genova, B. Girma, E.S. Kissel, A.N. Levy, S. MacCracken, P.R. Mastrandrea, and L.L.White (eds.)]. Cambridge University Press, Cambridge, United Kingdom and New York, NY, USA, pp. 229-269.{{rp|251}} In the arid regions of India, China, the US and Africa dry spells and drought are already affecting water availability.

Climate change is particularly likely to affect the Arctic, Africa, small islands, Asian megadeltas and the Middle East regions.{{citation |title=Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change |access-date=28 December 2018 |archive-url=https://web.archive.org/web/20181223030123/https://archive.ipcc.ch/publications_and_data/ar4/syr/en/main.html |url-status=live |at=[http://archive.ipcc.ch/publications_and_data/ar4/syr/en/mains3-3-3.html Sec. 3.3.3 Especially affected systems, sectors and regions] |chapter=Synthesis report |chapter-url=http://archive.ipcc.ch/publications_and_data/ar4/syr/en/main.html |archive-date=23 December 2018}}, in {{harvnb|IPCC AR4 SYR|2007}}.{{cite journal |last1=Waha |first1=Katharina |date=April 2017 |title=Climate change impacts in the Middle East and Northern Africa (MENA) region and their implications for vulnerable population groups |url=https://www.researchgate.net/publication/316057764 |url-status=live |journal=Regional Environmental Change |volume=17 |issue=6 |pages=1623–1638 |doi=10.1007/s10113-017-1144-2 |bibcode=2017REnvC..17.1623W |hdl=1871.1/15a62c49-fde8-4a54-95ea-dc32eb176cf4 |s2cid=134523218 |archive-url=https://web.archive.org/web/20210723103211/https://www.researchgate.net/publication/316057764_Climate_change_impacts_in_the_Middle_East_and_Northern_Africa_MENA_region_and_their_implications_for_vulnerable_population_groups |archive-date=23 July 2021 |access-date=25 May 2020|hdl-access=free }} Low-latitude, less-developed regions are most at risk of experiencing negative climate change impacts.{{rp|795–796}} The ten countries of the Association of Southeast Asian Nations (ASEAN) are among the most vulnerable in the world to the negative effects of climate change. ASEAN's climate mitigation efforts are not in proportion to the climate change threats the region faces.{{cite journal |last1=Overland |first1=Indra |last2=Sagbakken |first2=Haakon Fossum |last3=Chan |first3=Hoy-Yen |last4=Merdekawati |first4=Monika |last5=Suryadi |first5=Beni |last6=Utama |first6=Nuki Agya |last7=Vakulchuk |first7=Roman |date=December 2021 |title=The ASEAN climate and energy paradox |journal=Energy and Climate Change |volume=2 |page=100019 |doi=10.1016/j.egycc.2020.100019 |hdl-access=free |hdl=11250/2734506}}

{{Further|Climate change and cities|}}File:Overlap between future population distribution and extreme heat.jpgRegions inhabited by a third of the human population could become as hot as the hottest parts of the Sahara within 50 years. This would happen if greenhouse gas emissions continue to grow rapidly without a change in patterns of population growth and without migration. The projected average temperature of above {{Convert|29|C}} for these regions would be outside the "human temperature niche". This is a range for climate that is biologically suitable for humans. It is based on historical data of mean annual temperatures. The most affected regions have little adaptive capacity.{{cite news |date=5 May 2020 |title=Climate change: More than 3bn could live in extreme heat by 2070 |work=BBC News |url=https://www.bbc.co.uk/news/science-environment-52543589 |url-status=live |access-date=6 May 2020 |archive-url=https://web.archive.org/web/20200505153614/https://www.bbc.co.uk/news/science-environment-52543589 |archive-date=5 May 2020}}{{cite journal |last1=Xu |first1=Chi |last2=Kohler |first2=Timothy A. |last3=Lenton |first3=Timothy M. |last4=Svenning |first4=Jens-Christian |last5=Scheffer |first5=Marten |date=26 May 2020 |title=Future of the human climate niche|journal=Proceedings of the National Academy of Sciences |volume=117 |issue=21 |pages=11350–11355 |bibcode=2020PNAS..11711350X |doi=10.1073/pnas.1910114117 |pmc=7260949 |pmid=32366654 |doi-access=free}}

Increased extreme heat exposure from climate change and the urban heat island effect threatens urban settlements.{{Cite journal |last1=Tuholske |first1=Cascade |last2=Caylor |first2=Kelly |last3=Funk |first3=Chris |last4=Verdin |first4=Andrew |last5=Sweeney |first5=Stuart |last6=Grace |first6=Kathryn |last7=Peterson |first7=Pete |last8=Evans |first8=Tom |date=12 October 2021 |title=Global urban population exposure to extreme heat |journal=Proceedings of the National Academy of Sciences |volume=118 |issue=41 |pages=e2024792118 |bibcode=2021PNAS..11824792T |doi=10.1073/pnas.2024792118 |pmc=8521713 |pmid=34607944 |doi-access=free}} This is made worse by the loss of shade from urban trees that cannot withstand the heat stress.{{Cite journal |last1=Esperon-Rodriguez |first1=Manuel |last2=Tjoelker |first2=Mark G. |last3=Lenoir |first3=Jonathan |last4=Baumgartner |first4=John B. |last5=Beaumont |first5=Linda J. |last6=Nipperess |first6=David A. |last7=Power |first7=Sally A. |last8=Richard |first8=Benoît |last9=Rymer |first9=Paul D. |last10=Gallagher |first10=Rachael V. |date=October 2022 |title=Climate change increases global risk to urban forests |url=https://www.nature.com/articles/s41558-022-01465-8 |journal=Nature Climate Change |language=en |volume=12 |issue=10 |pages=950–955 |bibcode=2022NatCC..12..950E |doi=10.1038/s41558-022-01465-8 |issn=1758-6798 |s2cid=252401296}}

In 2019, the Crowther Lab from ETH Zurich paired the climatic conditions of 520 major cities worldwide with the predicted climatic conditions of cities in 2050. It found that 22% of the major cities would have climatic conditions that do not exist in any city today. For instance, 2050 London would have a climate similar to 2019 Melbourne in Australia. Athens and Madrid would be like Fez in Morocco. Nairobi in Kenya would be like Maputo in Mozambique. The Indian city Pune would be like Bamako in Mali and Bamako would be like Niamey in Niger. Brasilia would be like Goiania, both in Brazil.[https://crowtherlab.pageflow.io/cities-of-the-future-visualizing-climate-change-to-inspire-action#213121 Cities of the future: visualizing climate change to inspire action, current vs future cities] {{Webarchive|url=https://web.archive.org/web/20230108082440/https://crowtherlab.pageflow.io/cities-of-the-future-visualizing-climate-change-to-inspire-action#213121 |date=8 January 2023 }}, Crowther Lab, Department für Umweltsystemwissenschaften, Institut für integrative Biologie, ETH Zürich, zugegriffen: 11 July 2019.[https://journals.plos.org/plosone/article/file?id=10.1371/journal.pone.0217592&type=printable Understanding climate change from a global analysis of city analogues], Bastin J-F, Clark E, Elliott T, Hart S, van den Hoogen J, Hordijk I, et al. (2019), PLOS ONE 14(7): e0217592, Crowther Lab, Department for Environmental Systems Science, Institut for Integrative Biology, ETH Zürich, 10 July 2019.

{{Further|Effects of climate change on small island countries}}Low-lying cities and other settlements near the sea face multiple simultaneous risks from climate change. They face flooding risks from sea level rise. In addition they may face impacts from more severe storms, ocean acidification, and salt intrusion into the groundwater. Changes like continued development in exposed areas increase the risks that these regions face.Glavovic, B.C., R. Dawson, W. Chow, M. Garschagen, M. Haasnoot, C. Singh, and A. Thomas, 2022: [https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_CCP2.pdf Cross-Chapter Paper 2: Cities and Settlements by the Sea]. In: Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, US, pp. 2163–2194, {{doi|10.1017/9781009325844.019}}

File:Cyclone Nargis flooding before-and-after.jpg which was submerged by Cyclone Nargis.]]

Population density on the coasts is high. Estimates of the number of people at risk of coastal flooding from climate-driven sea level rise vary. Estimates range from 190 million[https://www.bbc.com/news/science-environment-50236882 Climate change: Sea level rise to affect 'three times more people'] {{Webarchive|url=https://web.archive.org/web/20200106151232/https://www.bbc.com/news/science-environment-50236882|date=6 January 2020}}, BBC News, 30 October 2019 to 300 million. It could even be 640 million in a worst-case scenario related to the instability of the Antarctic ice sheet.[https://www.theguardian.com/environment/2019/oct/29/rising-sea-levels-pose-threat-to-homes-of-300m-people-study Rising sea levels pose threat to homes of 300m people – study] {{Webarchive|url=https://web.archive.org/web/20191230044325/https://www.theguardian.com/environment/2019/oct/29/rising-sea-levels-pose-threat-to-homes-of-300m-people-study|date=30 December 2019}}, The Guardian, 29 October 2019{{Cite journal |last1=Kulp |first1=Scott A. |last2=Strauss |first2=Benjamin H. |date=29 October 2019 |title=New elevation data triple estimates of global vulnerability to sea-level rise and coastal flooding |journal=Nature Communications |volume=10 |issue=1 |page=4844 |bibcode=2019NatCo..10.4844K |doi=10.1038/s41467-019-12808-z |pmc=6820795 |pmid=31664024 |s2cid=204962583}} People are most affected in the densely-populated low-lying megadeltas of Asia and Africa.{{cite web |author=IPCC |year=2007 |title=3.3.1 Impacts on systems and sectors. In (section): Synthesis Report. In: Climate Change 2007: Synthesis Report. Contribution of Working Groups I, II and III to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (Core Writing Team, Pachauri, R.K and Reisinger, A. (eds.)) |url=http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains3-3-1.html |url-status=dead |archive-url=https://web.archive.org/web/20181103102842/http://www.ipcc.ch/publications_and_data/ar4/syr/en/mains3-3-1.html |archive-date=3 November 2018 |access-date=10 April 2010 |publisher=Book version: IPCC, Geneva, Switzerland. This version: IPCC website}}

Small island developing states are especially vulnerable. They are likely to experience more intense storm surges, salt water intrusion and coastal destruction.{{cite web |last1=Rasheed Hassan |first1=Hussain |last2=Cliff |first2=Valerie |date=24 September 2019 |title=For small island nations, climate change is not a threat. It's already here |url=https://www.weforum.org/agenda/2019/09/island-nations-maldives-climate-change/ |access-date=28 January 2021 |website=World Economic Fourm}} Low-lying small islands in the Pacific, Indian, and Caribbean regions even risk permanent inundation. This would displace their population.{{cite journal |last1=Barnett |first1=Jon |last2=Adger |first2=W. Neil |date=December 2003 |title=Climate Dangers and Atoll Countries |journal=Climatic Change |volume=61 |issue=3 |pages=321–337 |doi=10.1023/B:CLIM.0000004559.08755.88 |bibcode=2003ClCh...61..321B |s2cid=55644531}}{{cite journal |last1=Church |first1=John A. |last2=White |first2=Neil J. |last3=Hunter |first3=John R. |date=2006 |title=Sea-level rise at tropical Pacific and Indian Ocean islands |journal=Global and Planetary Change |volume=53 |issue=3 |pages=155–168 |bibcode=2006GPC....53..155C |doi=10.1016/j.gloplacha.2006.04.001}}

{{cite journal |last=Mimura |first=N |date=1999 |title=Vulnerability of island countries in the South Pacific to sea level rise and climate change |journal=Climate Research |volume=12 |pages=137–143 |bibcode=1999ClRes..12..137M |doi=10.3354/cr012137 |doi-access=free}}

On the islands of Fiji, Tonga and western Samoa, migrants from outer islands inhabit low and unsafe areas along the coasts. The entire populations of small atoll nations such as Kiribati, Maldives, the Marshall Islands, and Tuvalu are at risk of being displaced.{{cite journal |last=Tsosie |first=Rebecca |year=2007 |title=Indigenous People and Environmental Justice:The Impact of Climate Change |journal=University of Colorado Law Review |url=https://papers.ssrn.com/sol3/papers.cfm?abstract_id=1399659|volume=78 |pages=1625|ssrn=1399659 }}

This could raise issues of statelessness.

{{cite report|date=May 2011 |last=Park|first=Susan|title=Climate change and the risk of statelessness |url=https://www.unhcr.org/media/30513 |access-date=29 April 2023}}

Several factors increase their vulnerability. These are small size, isolation from other land, low financial resources, and lack of protective infrastructure.

{{anchor|Climate doom loop}}

File:2020- Climate change's projected damage to GDP growth.svg vary widely, and even this approach to predicting damage does not consider impacts of climate tipping points, climate-driven extreme events, human health impacts, resource or migration-driven conflict, geopolitical tension, nature-driven risks, or sea level rise.{{cite web |last1=Trust |first1=Sandy |last2=Saye |first2=Lucy |last3=Bettis |first3=Oliver |last4=Bedenham |first4=Georgina |last5=Hampshire |first5=Oliver |last6=Lenton |first6=Timothy M. |last7=Abrams |first7=Jesse F |title=Planetary Solvency–finding our balance with nature Global risk management for human prosperity |url=https://actuaries.org.uk/document-library/thought-leadership/thought-leadership-campaigns/climate-papers/planetary-solvency-finding-our-balance-with-nature/ |publisher=Institute and Faculty of Actuaries |pages=12–13 (Figure 2) |archive-url=https://web.archive.org/web/20250117012930/https://actuaries.org.uk/document-library/thought-leadership/thought-leadership-campaigns/climate-papers/planetary-solvency-finding-our-balance-with-nature/ |archive-date=17 January 2025 |date=January 2025 |url-status=live}} ● Trust et al. cite {{cite journal |last1=Kotz |first1=Maximilian |last2=Levermann |first2=Anders |last3=Wenz |first3=Leonie |title=The economic commitment of climate change |journal=Nature |date=17 April 2024 |volume=628 |pages=551–557 |doi=10.1038/s41586-024-07732-2|pmc=11236700 }}]]

Climate change has many impacts on society.{{cite journal |last1=Dietz |first1=Thomas |last2=Shwom |first2=Rachael L. |last3=Whitley |first3=Cameron T. |title=Climate Change and Society |journal=Annual Review of Sociology |date=2020 |volume=46 |issue=1 |pages=135–158 |doi=10.1146/annurev-soc-121919-054614 |doi-access=free}} It affects health, the availability of drinking water and food, inequality and economic growth. The effects of climate change are often interlinked. They can exacerbate each other as well as existing vulnerabilities.{{cite journal |last1=O'Brien |first1=Karen L |last2=Leichenko |first2=Robin M |date=1 October 2000 |title=Double exposure: assessing the impacts of climate change within the context of economic globalization |journal=Global Environmental Change |volume=10 |issue=3 |pages=221–232 |doi=10.1016/S0959-3780(00)00021-2 |bibcode=2000GEC....10..221O }}{{cite journal |last1=Zhang |first1=Li |last2=Chen |first2=Fu |last3=Lei |first3=Yongdeng |year=2020 |title=Climate change and shifts in cropping systems together exacerbate China's water scarcity |journal=Environmental Research Letters |volume=15 |issue=10 |page=104060 |bibcode=2020ERL....15j4060Z |doi=10.1088/1748-9326/abb1f2 |s2cid=225127981|doi-access=free }}{{cite journal |last1=Cramer |first1=Wolfgang |last2=Guiot |first2=Joël |last3=Fader |first3=Marianela |last4=Garrabou |first4=Joaquim |last5=Gattuso |first5=Jean-Pierre |last6=Iglesias |first6=Ana |last7=Lange |first7=Manfred A. |last8=Lionello |first8=Piero |last9=Llasat |first9=Maria Carmen |last10=Paz |first10=Shlomit |last11=Peñuelas |first11=Josep |date=November 2018 |title=Climate change and interconnected risks to sustainable development in the Mediterranean |url=http://ddd.uab.cat/record/203562 |journal=Nature Climate Change |volume=8 |issue=11 |pages=972–980 |bibcode=2018NatCC...8..972C |doi=10.1038/s41558-018-0299-2 |s2cid=92556045 |first13=Andrea |last14=Tsimplis |first12=Maria |last13=Toreti |first15=Elena |last15=Xoplaki |first14=Michael N. |last12=Snoussi|hdl=10261/172731 |hdl-access=free }} Some areas may become too hot for humans to live in.{{cite news |last1=Watts |first1=Jonathan |date=5 May 2020 |title=One billion people will live in insufferable heat within 50 years – study |work=The Guardian |url=https://www.theguardian.com/environment/2020/may/05/one-billion-people-will-live-in-insufferable-heat-within-50-years-study |url-status=live |access-date=7 May 2020 |archive-url=https://web.archive.org/web/20200507000700/https://www.theguardian.com/environment/2020/may/05/one-billion-people-will-live-in-insufferable-heat-within-50-years-study |archive-date=7 May 2020}}{{cite journal |last1=Xu |first1=Chi |last2=M. Lenton |first2=Timothy |last3=Svenning |first3=Jens-Christian |last4=Scheffer |first4=Marten |date=26 May 2020 |title=Future of the human climate niche |journal=Proceedings of the National Academy of Sciences of the United States of America |volume=117 |issue=21 |pages=11350–11355 |doi=10.1073/pnas.1910114117 |pmc=7260949 |pmid=32366654 |bibcode=2020PNAS..11711350X |doi-access=free}} Climate-related changes or disasters may lead people in some areas to move to other parts of the country or to other countries.

Some scientists describe the effects of climate change, with continuing increases in greenhouse gas emissions, as a "climate emergency" or "climate crisis".{{cite journal |last1=Ripple |first1=William J |last2=Wolf |first2=Christopher |last3=Newsome |first3=Thomas M |last4=Barnard |first4=Phoebe |last5=Moomaw |first5=William R |title=Corrigendum: World Scientists' Warning of a Climate Emergency |journal=BioScience |date=1 January 2020 |volume=70 |issue=1 |pages=100 |doi=10.1093/biosci/biz152 |doi-access=free }}[https://www.smithsonianmag.com/science-nature/scientists-around-world-declare-climate-emergency-180973462/ Scientists Around the World Declare 'Climate Emergency'] {{Webarchive|url=https://web.archive.org/web/20191216235752/https://www.smithsonianmag.com/science-nature/scientists-around-world-declare-climate-emergency-180973462/|date=16 December 2019}}, Smithsonian Magazine, 5 November 2019 Some researchers[https://edition.cnn.com/2019/06/04/health/climate-change-existential-threat-report-intl/index.html Climate change could pose 'existential threat' by 2050: report] {{Webarchive|url=https://web.archive.org/web/20200127102054/https://edition.cnn.com/2019/06/04/health/climate-change-existential-threat-report-intl/index.html|date=27 January 2020}}, CNN, 5 June 2019.{{cite journal |last1=Lenton |first1=Timothy M. |last2=Rockström |first2=Johan |last3=Gaffney |first3=Owen |last4=Rahmstorf |first4=Stefan |last5=Richardson |first5=Katherine |last6=Steffen |first6=Will |last7=Schellnhuber |first7=Hans Joachim |title=Climate tipping points — too risky to bet against |journal=Nature |date=November 2019 |volume=575 |issue=7784 |pages=592–595 |doi=10.1038/d41586-019-03595-0 |pmid=31776487 |bibcode=2019Natur.575..592L |hdl=10871/40141 |s2cid=208330359 |hdl-access=free }} and activists[https://www.theguardian.com/commentisfree/2019/sep/25/greta-thunberg-showed-the-world-what-it-means-to-lead Greta Thunberg showed the world what it means to lead] {{Webarchive|url=https://web.archive.org/web/20211029085350/https://www.theguardian.com/commentisfree/2019/sep/25/greta-thunberg-showed-the-world-what-it-means-to-lead|date=29 October 2021}}, The Guardian, 25 September 2019 describe them as an existential threat to civilization. Some define these threats under climate security. The consequences of climate change, and the failure to address it, can distract people from tackling its root causes. This leads to what some researchers have termed a "climate doom loop".{{cite web |last1=Laybourn |first1=Laurie |last2=Throp |first2=Henry |last3=Sherman |first3=Suzannah |website=Institute for Public Policy Research (IPPR) |title=1.5 °C – Dead or Alive? The Risks to Transformational Change Reaching and Breaching the Paris Agreement Goal |url=https://www.ippr.org/files/2023-02/1676546139_1.5c-dead-or-alive-feb23.pdf |publisher=Chatham House, the Royal Institute of International Affairs |archive-url=https://web.archive.org/web/20230309035603/https://www.ippr.org/files/2023-02/1676546139_1.5c-dead-or-alive-feb23.pdf |archive-date=9 March 2023 |date=February 2023 |url-status=live}} Explained by Tigue, Kristoffer, {{cite web |title=What's a Climate 'Doom Loop?' These Researchers Fear We're Heading Into One |url=https://insideclimatenews.org/todaysclimate/whats-a-climate-doom-loop-these-researchers-fear-were-heading-into-one/ |publisher=Inside Climate News |archive-url=https://web.archive.org/web/20230306041102/https://insideclimatenews.org/todaysclimate/whats-a-climate-doom-loop-these-researchers-fear-were-heading-into-one/ |archive-date=6 March 2023 |date=17 February 2023 |url-status=live}}

{{Further|Climate migration|Climate change adaptation#Migration and managed retreat}}

Displacement is when people move within a country. Migration is when they move to another country. Some people use the terms interchangeably. Climate change affects displacement in several ways. More frequent and severe weather-related disasters may increase involuntary displacement. These destroy homes and habitats. Climate impacts such as desertification and rising sea levels gradually erode livelihoods. They force communities to abandon traditional homelands. Other forms of migration are adaptive and voluntary. They are based on individual or household decisions.Cissé, G., R. McLeman, H. Adams, P. Aldunce, K. Bowen, D. Campbell-Lendrum, S. Clayton, K.L. Ebi, J. Hess, C. Huang, Q. Liu, G. McGregor, J. Semenza, and M.C. Tirado, 2022: [https://www.ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter07.pdf Health, Wellbeing, and the Changing Structure of Communities.] In: [https://www.ipcc.ch/report/ar6/wg2/ Climate Change 2022: Impacts, Adaptation and Vulnerability. Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change] [H.-O. Pörtner, D.C. Roberts, M. Tignor, E.S. Poloczanska, K. Mintenbeck, A. Alegría, M. Craig, S. Langsdorf, S. Löschke, V. Möller, A. Okem, B. Rama (eds.)]. Cambridge University Press, Cambridge, UK and New York, NY, US, pp. 1041–1170, {{doi|10.1017/9781009325844.009}}{{rp|1079}} On the other hand, some households may fall into poverty or get poorer due to climate change. This limits their ability to move to less affected areas.{{Cite journal |last1=Kaczan |first1=David J. |last2=Orgill-Meyer |first2=Jennifer |date=2020 |title=The impact of climate change on migration: a synthesis of recent empirical insights |journal=Climatic Change |volume=158 |issue=3 |pages=281–300 |bibcode=2020ClCh..158..281K |doi=10.1007/s10584-019-02560-0 |s2cid=207988694}}

Migration due to climate and weather is usually within countries. But it is long-distance. Slow-onset disasters such as droughts and heat are more likely to cause long-term migration than weather disasters like floods. Migration due to desertification and reduced soil fertility is typically from rural areas in developing countries to towns and cities.{{citation |author=The World Bank |title=Managing social risks: Empower communities to protect themselves |access-date=29 August 2011 |archive-url=https://web.archive.org/web/20110507173000/http://siteresources.worldbank.org/INTWDR2010/Resources/5287678-1226014527953/Chapter-2.pdf |url-status=live |chapter=Part One: Chapter 2: Reducing Human Vulnerability: Helping People Help Themselves |date=6 November 2009 |publisher=World Bank Publications |isbn=9780821379882 |chapter-url=https://books.google.com/books?id=MGOJs900Q-MC |archive-date=7 May 2011}}{{rp|109}}

According to the Internal Displacement Monitoring Centre, extreme weather events displaced approximately 30 million people in 2020. Violence and wars displaced approximately 10 million in the same year. There may have been a contribution of climate change to these conflicts.{{cite book |title=GRID Internal displacement in a changing climate |date=2021 |publisher=Internal Displacement Monitoring Center |pages=42–53 |url=https://www.internal-displacement.org/sites/default/files/publications/documents/grid2021_idmc.pdf#page=42 |access-date=24 May 2021}}{{cite news |last1=Niranjan |first1=Ajit |title=Extreme Weather Displaces Record Numbers of People as Temperatures Rise |url=https://www.ecowatch.com/extreme-weather-climate-refugees-2653071338.html |access-date=24 May 2021 |agency=Ecowatch |date=21 May 2021}} In 2018, the World Bank estimated that climate change will cause internal migration of between 31 and 143 million people by 2050. This would be as they escape crop failures, water scarcity, and sea level rise. The study covered only Sub-Saharan Africa, South Asia, and Latin America.[https://www.nationalgeographic.com/news/2018/03/climate-migrants-report-world-bank-spd/ 143 Million People May Soon Become Climate Migrants] {{Webarchive|url=https://web.archive.org/web/20191219010304/https://www.nationalgeographic.com/news/2018/03/climate-migrants-report-world-bank-spd/|date=19 December 2019}}, National Geographic, 19 March 2018{{Cite book |last1=Kumari Rigaud |first1=Kanta |url=https://openknowledge.worldbank.org/bitstream/handle/10986/29461/WBG_ClimateChange_Final.pdf |title=Groundswell: preparing for internal climate migration |last2=de Sherbinin |first2=Alex |last3=Jones |first3=Bryan |publisher=The World Bank |year=2018 |location=Washington DC |page=xxi |display-authors=etal |access-date=29 December 2019 |archive-url=https://web.archive.org/web/20200102172649/https://openknowledge.worldbank.org/bitstream/handle/10986/29461/WBG_ClimateChange_Final.pdf |archive-date=2 January 2020 |url-status=live}}

File:Majuro_-_Main_Atoll_of_the_RMI.jpg, reaching the edge of a village (from the documentary One Word)]]

{{Main|Climate security}}

File:Overlap between state fragility, extreme heat, and nuclear and biological catastrophic hazards.jpgs]]

Climate change is unlikely to cause international wars in the foreseeable future. However, climate change can increase the risk for intrastate conflicts, such as civil wars, communal violence, or protests.{{cite journal |last1=Mach |first1=Katharine J. |last2=Kraan |first2=Caroline M. |last3=Adger |first3=W. Neil |last4=Buhaug |first4=Halvard |last5=Burke |first5=Marshall |last6=Fearon |first6=James D. |last7=Field |first7=Christopher B. |last8=Hendrix |first8=Cullen S. |last9=Maystadt |first9=Jean-Francois |last10=O'Loughlin |first10=John |last11=Roessler |first11=Philip |last12=Scheffran |first12=Jürgen |last13=Schultz |first13=Kenneth A. |last14=von Uexkull |first14=Nina |date=July 2019 |title=Climate as a risk factor for armed conflict |url=https://eprints.lancs.ac.uk/id/eprint/134710/1/Mach_2019_accepted_manuscript.pdf |url-status=dead |journal=Nature |volume=571 |issue=7764 |pages=193–197 |bibcode=2019Natur.571..193M |doi=10.1038/s41586-019-1300-6 |pmid=31189956 |s2cid=186207310 |archive-url=https://web.archive.org/web/20220412022049/https://eprints.lancs.ac.uk/id/eprint/134710/1/Mach_2019_accepted_manuscript.pdf |archive-date=12 April 2022 |access-date=21 November 2022 |hdl=10871/37969}} The IPCC Sixth Assessment Report concludes: "Climate hazards have affected armed conflict within countries (medium confidence), but the influence of climate is small compared to socio-economic, political, and cultural factors (high confidence)."{{Cite book |last=Intergovernmental Panel on Climate Change (IPCC) |url=https://www.cambridge.org/core/books/climate-change-2022-impacts-adaptation-and-vulnerability/161F238F406D530891AAAE1FC76651BD |title=Climate Change 2022 – Impacts, Adaptation and Vulnerability: Working Group II Contribution to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |date=2023 |publisher=Cambridge University Press |location=Cambridge |page=1045 |doi=10.1017/9781009325844|isbn=978-1-009-32584-4 }}

Climate change can increase conflict risks by causing tensions about scarce resources like food, water and land, by weakening state institutions, by reducing the opportunity costs for impoverished individuals to join armed groups, and by causing tensions related to (climate-induced) migration.{{cite journal |last1=Koubi |first1=Vally |year=2019 |title=Climate Change and Conflict |journal=Annual Review of Political Science |volume=22 |pages=343–360 |doi=10.1146/annurev-polisci-050317-070830 |doi-access=free}} Efforts to mitigate or adapt to climate change can also cause conflicts, for instance due to higher food and energy prices or when people are forcibly re-located from vulnerable areas.{{Cite journal |last1=Gilmore |first1=Elisabeth A. |last2=Buhaug |first2=Halvard |date=17 June 2021 |title=Climate mitigation policies and the potential pathways to conflict: Outlining a research agenda |journal=WIREs Climate Change |language=en |volume=12 |issue=5 |pages=e722 |doi=10.1002/wcc.722 |issn=1757-7780 |pmc=8459245 |pmid=34594401|bibcode=2021WIRCC..12E.722G }}{{Cite journal |last=Siddiqi |first=Ayesha |date=20 April 2022 |title=The missing subject: Enabling a postcolonial future for climate conflict research |journal=Geography Compass |language=en |volume=16 |issue=5 |doi=10.1111/gec3.12622 |bibcode=2022GComp..16E2622S |issn=1749-8198|doi-access=free }}

Research has shown that climate change is not the most important conflict driver, and that it can only affect conflict risks under certain circumstances. Relevant context factors include agricultural dependence, a history of political instability, poverty, and the political exclusion of ethnic groups.{{Cite journal |last1=Ide |first1=Tobias |last2=Brzoska |first2=Michael |last3=Donges |first3=Jonathan F. |last4=Schleussner |first4=Carl-Friedrich |date=2020-05-01 |title=Multi-method evidence for when and how climate-related disasters contribute to armed conflict risk |url=https://www.sciencedirect.com/science/article/pii/S0959378019307307 |journal=Global Environmental Change |volume=62 |pages=102063 |doi=10.1016/j.gloenvcha.2020.102063 |bibcode=2020GEC....6202063I |issn=0959-3780}}{{Cite journal |last1=von Uexkull |first1=Nina |last2=Croicu |first2=Mihai |last3=Fjelde |first3=Hanne |last4=Buhaug |first4=Halvard |date=17 October 2016 |title=Civil conflict sensitivity to growing-season drought |journal=Proceedings of the National Academy of Sciences |language=en |volume=113 |issue=44 |pages=12391–12396 |doi=10.1073/pnas.1607542113 |doi-access=free |issn=0027-8424 |pmc=5098672 |pmid=27791091|bibcode=2016PNAS..11312391V }}{{Cite journal |last=Ide |first=Tobias |date=2023 |title=Rise or Recede? How Climate Disasters Affect Armed Conflict Intensity |journal=International Security |volume=47 |issue=4 |pages=50–78 |doi=10.1162/isec_a_00459 |issn=0162-2889|doi-access=free }} Climate change has thus been described as a "threat multiplier".{{cite journal |last=Spaner |first=J S |author2=LeBali, H |date=October 2013 |title=The Next Security Frontier |url=http://www.usni.org/magazines/proceedings/2013-10/next-security-frontier |url-status=live |journal=Proceedings of the United States Naval Institute |volume=139 |issue=10 |pages=30–35 |archive-url=https://web.archive.org/web/20181107014339/https://www.usni.org/magazines/proceedings/2013-10/next-security-frontier |archive-date=7 November 2018 |access-date=23 November 2015}} Yet, an impact of climate change on specific conflicts like the Syrian civil war{{Cite journal |last1=Dinc |first1=Pinar |last2=Eklund |first2=Lina |date=2023-07-01 |title=Syrian farmers in the midst of drought and conflict: the causes, patterns, and aftermath of land abandonment and migration |journal=Climate and Development |volume=16 |issue=5 |language=en |pages=349–362 |doi=10.1080/17565529.2023.2223600 |issn=1756-5529|doi-access=free }}{{Cite journal |last1=Ash |first1=Konstantin |last2=Obradovich |first2=Nick |date=2020 |title=Climatic Stress, Internal Migration, and Syrian Civil War Onset |url=http://journals.sagepub.com/doi/10.1177/0022002719864140 |journal=Journal of Conflict Resolution |language=en |volume=64 |issue=1 |pages=3–31 |doi=10.1177/0022002719864140 |issn=0022-0027}} or the armed conflict in Darfur{{Cite journal |last=De Juan |first=Alexander |date=2015-03-01 |title=Long-term environmental change and geographical patterns of violence in Darfur, 2003–2005 |url=https://www.sciencedirect.com/science/article/pii/S0962629814000821 |journal=Political Geography |volume=45 |pages=22–33 |doi=10.1016/j.polgeo.2014.09.001 |issn=0962-6298}}{{cite news |last1=Perez |first1=Ines |date=4 March 2013 |title=Climate Change and Rising Food Prices Heightened Arab Spring |url=https://www.scientificamerican.com/article/climate-change-and-rising-food-prices-heightened-arab-spring/ |url-status=live |archive-url=https://web.archive.org/web/20180820074131/https://www.scientificamerican.com/article/climate-change-and-rising-food-prices-heightened-arab-spring/ |archive-date=20 August 2018 |access-date=21 August 2018 |work=Republished with permission by Scientific American |publisher=Environment & Energy Publishing, LLC}} remains hard to prove.

Climate change does not affect people within communities in the same way. It can have a bigger impact on vulnerable groups such as women, the elderly, religious minorities and refugees than on others.{{cite book |last1=Begum |first1=Rawshan Ara |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Lempert |first2=Robert |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |chapter=Chapter 1: Point of Departure and Key Concept |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_Chapter01.pdf|page=170}}

• People living with disability. Climate impacts on disabled people have been identified by activists and advocacy groups as well as through the UNHCR adopting a resolution on climate change and the rights of people with disabilities.{{Cite web |last1=CounterAct |last2=Women's Climate Justice Collective |date=2020-05-04 |title=Climate Justice and Feminism Resource Collection |url=https://commonslibrary.org/climate-justice-feminism/ |access-date=2024-07-08 |website=The Commons Social Change Library |language=en-AU}}
• People living in poverty: Climate change disproportionally affects poor people in low-income communities and developing countries around the world. Those in poverty have a higher chance of experiencing the ill-effects of climate change, due to their increased exposure and vulnerability.{{cite journal |last=Rayner |first=S. and E.L. Malone |year=2001 |title=Climate Change, Poverty, and Intragernerational Equity: The National Leve |journal=International Journal of Global Environmental Issues |series=1 |volume=I |issue=2 |pages=175–202 |doi=10.1504/IJGENVI.2001.000977}} A 2020 World Bank paper estimated that between 32 million to 132 million additional people will be pushed into extreme poverty by 2030 due to climate change.{{Cite web |date=September 2020 |title=Revised Estimates of the Impact of Climate Change on Extreme Poverty by 2030 |url=http://documents1.worldbank.org/curated/en/706751601388457990/pdf/Revised-Estimates-of-the-Impact-of-Climate-Change-on-Extreme-Poverty-by-2030.pdf |access-date= }}
• Women: Climate change increases gender inequality.{{cite journal |last1=Eastin |first1=Joshua |title=Climate change and gender equality in developing states |journal=World Development |date=1 July 2018 |volume=107 |pages=289–305 |doi=10.1016/j.worlddev.2018.02.021 |s2cid=89614518 }} It reduces women's ability to be financially independent,{{Cite journal |last1=Goli |first1=Imaneh |last2=Omidi Najafabadi |first2=Maryam |last3=Lashgarara |first3=Farhad |date=9 March 2020 |title=Where are We Standing and Where Should We Be Going? Gender and Climate Change Adaptation Behavior |journal=Journal of Agricultural and Environmental Ethics |volume=33 |issue=2 |pages=187–218 |doi=10.1007/s10806-020-09822-3 |bibcode=2020JAEE...33..187G |s2cid=216404045 }} and has an overall negative impact on the social and political rights of women. This is especially the case in economies that are heavily based on agriculture.
• Indigenous peoples: Indigenous communities tend to rely more on the environment for food and other necessities. This makes them more vulnerable to disturbances in ecosystems.{{cite book |last1=Pörtner |first1=H.-O. |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Roberts |first2=D.C. |last3=Adams |first3=H. |last4=Adelekan |first4=I. |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=47 |chapter=Technical Summary |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_TechnicalSummary.pdf}} Indigenous communities across the globe generally have bigger economic disadvantages than non-indigenous communities. This is due to the oppression they have experienced. These disadvantages include less access to education and jobs and higher rates of poverty. All this makes them more vulnerable to climate change.{{Cite journal |last=Ford |first=James D. |date=17 May 2012 |title=Indigenous Health and Climate Change |journal=American Journal of Public Health |volume=102 |issue=7 |pages=1260–1266 |doi=10.2105/AJPH.2012.300752 |pmc=3477984 |pmid=22594718 }}
• Children: The Lancet review on health and climate change lists children among the worst-affected by global warming.{{Cite journal |last1=Watts |first1=Nick |last2=Amann |first2=Markus |last3=Arnell |first3=Nigel |last4=Ayeb-Karlsson |first4=Sonja |last5=Belesova |first5=Kristine |last6=Boykoff |first6=Maxwell |last7=Byass |first7=Peter |last8=Cai |first8=Wenjia |last9=Campbell-Lendrum |first9=Diarmid |last10=Capstick |first10=Stuart |last11=Chambers |first11=Jonathan |date=16 November 2019 |title=The 2019 report of The Lancet Countdown on health and climate change: ensuring that the health of a child born today is not defined by a changing climate |journal=Lancet |volume=394 |issue=10211 |pages=1836–1878 |doi=10.1016/S0140-6736(19)32596-6 |pmid=31733928 |bibcode=2019Lanc..394.1836W |s2cid=207976337 |url=http://sro.sussex.ac.uk/id/eprint/88053/4/__smbhome.uscs.susx.ac.uk_tjk30_Documents_The%202019%20Report%20of%20the%20Lancet%20Countdown%20-%20revised.pdf }} Children are 14–44 percent more likely to die from environmental factors.{{Cite journal |last1=Bartlett |first1=Sheridan |year=2008 |title=Climate change and urban children: Impacts and implications for adaptation in low- and middle-income countries |journal=Environment and Urbanization |volume=20 |issue=2 |pages=501–519 |doi=10.1177/0956247808096125 |bibcode=2008EnUrb..20..501B |s2cid=55860349}}

{{Main|Climate change and civilizational collapse|Global catastrophe scenarios#Climate change}}

Climate change has long been described as a severe risk to humans. Climate change as an existential threat has emerged as a key theme in the climate movement. People from small island nations also use this theme. There has not been extensive research in this topic. Existential risks are threats that could cause the extinction of humanity or destroy the potential of intelligent life on Earth. Key risks of climate change do not fit that definition. However, some key climate risks do have an impact people's ability to survive. For instance, areas may become too hot to survive, or sea level rise may make it impossible to live at a specific location.{{cite web |last1=Pester |first1=Patrick |title=Could climate change make humans go extinct? |url=https://www.livescience.com/climate-change-humans-extinct.html |website=Live Science |date=30 August 2021 |access-date=31 August 2021 |archive-date=30 August 2021 |archive-url=https://web.archive.org/web/20210830224155/https://www.livescience.com/climate-change-humans-extinct.html |url-status=live }}{{cite journal |last1=Steffen |first1=Will |last2=Persson |first2=Åsa |last3=Deutsch |first3=Lisa |last4=Zalasiewicz |first4=Jan |last5=Williams |first5=Mark |last6=Richardson |first6=Katherine |last7=Crumley |first7=Carole |last8=Crutzen |first8=Paul |last9=Folke |first9=Carl |last10=Gordon |first10=Line |last11=Molina |first11=Mario |last12=Ramanathan |first12=Veerabhadran |last13=Rockström |first13=Johan |last14=Scheffer |first14=Marten |last15=Schellnhuber |first15=Hans Joachim |last16=Svedin |first16=Uno |title=The Anthropocene: From Global Change to Planetary Stewardship |journal=Ambio |date=12 October 2011 |volume=40 |issue=7 |pages=739–761 |doi=10.1007/s13280-011-0185-x |pmid=22338713 |pmc=3357752 |bibcode=2011Ambio..40..739S }}{{Cite journal |last1=Huggel |first1=Christian |last2=Bouwer |first2=Laurens M. |last3=Juhola |first3=Sirkku |last4=Mechler |first4=Reinhard |last5=Muccione |first5=Veruska |last6=Orlove |first6=Ben |last7=Wallimann-Helmer |first7=Ivo |date=2022-09-12 |title=The existential risk space of climate change |url=https://doi.org/10.1007/s10584-022-03430-y |journal=Climatic Change |language=en |volume=174 |issue=1 |pages=8 |doi=10.1007/s10584-022-03430-y |issn=1573-1480 |pmc=9464613 |pmid=36120097|bibcode=2022ClCh..174....8H }} Text was copied from this source, which is available under a [https://creativecommons.org/licenses/by/4.0/ Creative Commons Attribution 4.0 International License]

As of October 2024, the possibility of societal collapse became more probable, the number of articles speaking about climate change and societal collapse increased sharply. Leading climate scientists emphasize that "“Climate change is a glaring symptom of a deeper systemic issue: ecological overshoot, [which] is an inherently unstable state that cannot persist indefinitely". To prevent it, they propose phase down fossil fuels, reduce methane emissions, overconsumption, and birth rate, switch to plant-based food, protect and restore ecosystems and adopt an ecological, post-growth economics which includes social justice. Climate change education should be integrated into core curriculums worldwide.{{cite journal |title=The 2024 state of the climate report: Perilous times on planet Earth |journal=BioScience |date=8 October 2024 |doi=10.1093/biosci/biae087 |url=https://academic.oup.com/bioscience/advance-article/doi/10.1093/biosci/biae087/7808595 |access-date=29 October 2024 |last1=Ripple |first1=William J. |last2=Wolf |first2=Christopher |last3=Gregg |first3=Jillian W. |last4=Rockström |first4=Johan |last5=Mann |first5=Michael E. |last6=Oreskes |first6=Naomi |last7=Lenton |first7=Timothy M. |last8=Rahmstorf |first8=Stefan |last9=Newsome |first9=Thomas M. |last10=Xu |first10=Chi |last11=Svenning |first11=Jens-Christian |last12=Pereira |first12=Cássio Cardoso |last13=Law |first13=Beverly E. |last14=Crowther |first14=Thomas W. |pages=biae087 |doi-access=free }}{{cite news |last1=Carrington |first1=Damian |title=Earth's 'vital signs' show humanity's future in balance, say climate experts |url=https://www.theguardian.com/environment/2024/oct/08/earths-vital-signs-show-humanitys-future-in-balance-say-climate-experts |access-date=29 October 2024 |agency=The Guardian |publisher=Bioscience |date=8 October 2024}}

{{Main|Economic analysis of climate change}}

File:Kotz 2024 aggregate impacts map.png

Economic forecasts of the impact of global warming vary considerably. The impacts are worse if there is insufficient adaptation.{{cite book |last1=Pörtner |first1=H.-O. |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Roberts |first2=D.C. |last3=Adams |first3=H. |last4=Adelekan |first4=I. |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=67 |chapter=Technical Summary |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_TechnicalSummary.pdf}} Economic modelling may underrate the impact of catastrophic climatic changes. When estimating losses, economists choose a discount rate. This determines how much one prefers to have goods or cash now compared to at a future date. Using a high discount rate may understate economic losses. This is because losses for future generations weigh less heavily.{{Cite journal |last1=Kompas |first1=Tom |last2=Pham |first2=Van Ha |last3=Che |first3=Tuong Nhu |date=2018 |title=The Effects of Climate Change on GDP by Country and the Global Economic Gains From Complying With the Paris Climate Accord |journal=Earth's Future |volume=6 |issue=8 |pages=1153–1173 |bibcode=2018EaFut...6.1153K |doi=10.1029/2018EF000922 |doi-access=free |hdl-access=free |hdl=1885/265534}}

Economic impacts are bigger the more the temperature rises.* {{Cite book |author=IPCC |author-link=IPCC |title={{Harvnb|IPCC AR5 WG2 A|2014}} |year=2014 |page=12 |chapter=Summary for Policymakers |ref={{harvid|IPCC AR5 WG2 Summary for Policymakers|2014}} |access-date=15 February 2020 |chapter-url=https://archive.ipcc.ch/pdf/assessment-report/ar5/wg2/ar5_wgII_spm_en.pdf |archive-url=https://web.archive.org/web/20191219013825/https://archive.ipcc.ch/pdf/assessment-report/ar5/wg2/ar5_wgII_spm_en.pdf |archive-date=19 December 2019 |url-status=live}} Scientists have compared impacts with warming of 1.5 °C (2.7 °F) and a level of 3.66 °C (6.59 °F). They use this higher figure to represent no efforts to stop emissions. They found that total damages at 1.5 °C were 90% less than at 3.66 °C.{{rp|256}} One study found that global GDP at the end of the century would be 3.5% less if warming is limited to {{Convert|3|C-change}}. This study excludes the potential effect of tipping points. Another study found that excluding tipping points underestimates the global economic impact by a factor of two to eight.{{rp|256}} Another study found that a temperature rise of {{Convert|2|C-change}} by 2050 would reduce global GDP by 2.5%–7.5%. By 2100 in this scenario the temperature would rise by {{Convert|4|C-change}}. This could reduce global GDP by 30% in the worst case.{{cite web |last1=Koning Beals |first1=Rachel |title=Global GDP will suffer at least a 3% hit by 2050 from unchecked climate change, say economists |url=https://www.marketwatch.com/story/global-gdp-will-suffer-at-least-a-3-hit-by-2050-from-unchecked-climate-change-say-economists-2019-11-20 |url-status=live |archive-url=https://web.archive.org/web/20200329094156/https://www.marketwatch.com/story/global-gdp-will-suffer-at-least-a-3-hit-by-2050-from-unchecked-climate-change-say-economists-2019-11-20 |archive-date=29 March 2020 |access-date=29 March 2020 |website=MarketWatch}} A 2024 study, which checked the data from the last 120 years, found that climate change has already reduced welfare by 29% and further temperature rise will rise the number to 47%. The temperature rise during the years 1960-2019 alone has cut current GDP per capita by 18%. A 1 degree warming reduces global GDP by 12%. An increase of 3 degrees by 2100, will reduce capital by 50%. The effects are similar to experiencing the 1929 Great Depression permanently. The correct social cost of carbon according to the study is 1065 dollars per tonne of CO2.{{cite book |last1=Bilal |first1=Adrien |last2=R. Känzig |first2=Diego |title=THE MACROECONOMIC IMPACT OF CLIMATE CHANGE: GLOBAL VS. LOCAL TEMPERATURE |date=August 2024 |publisher=NATIONAL BUREAU OF ECONOMIC RESEARCH |location=1050 Massachusetts Avenue Cambridge, MA 02138 |pages=1, 4, 5, 38, 39 |url=https://www.nber.org/system/files/working_papers/w32450/w32450.pdf |access-date=8 November 2024}}{{cite news |title=1°C global temperature rise could slash GDP by 12%, warns environmentalists |url=https://www.indiatoday.in/information/story/1degc-global-temperature-rise-could-slash-gdp-by-12-warns-environmentalists-2617153-2024-10-15 |access-date=8 November 2024 |agency=India Today |date=15 October 2024}}

Global losses reveal rapidly rising costs due to extreme weather events since the 1970s.{{rp|110}} Socio-economic factors have contributed to the observed trend of global losses. These factors include population growth and increased wealth.{{Citation |last=Bouwer |first=Laurens M. |title=Observed and Projected Impacts from Extreme Weather Events: Implications for Loss and Damage |date=2019 |work=Loss and Damage from Climate Change: Concepts, Methods and Policy Options |pages=63–82 |editor-last=Mechler |editor-first=Reinhard |series=Climate Risk Management, Policy and Governance |place=Cham |publisher=Springer International Publishing |doi=10.1007/978-3-319-72026-5_3 |isbn=978-3-319-72026-5 |editor2-last=Bouwer |editor2-first=Laurens M. |editor3-last=Schinko |editor3-first=Thomas |editor4-last=Surminski |editor4-first=Swenja |doi-access=free}} Regional climatic factors also play a role. These include changes in precipitation and flooding events. It is difficult to quantify the relative impact of socio-economic factors and climate change on the observed trend.{{citation |author=IPCC |title=Synthesis Report |url=http://www.grida.no/climate/ipcc_tar/vol4/english/016.htm |access-date=21 June 2012 |archive-url=https://web.archive.org/web/20160305033232/http://www.grida.no/climate/ipcc_tar/vol4/english/016.htm |archive-date=5 March 2016 |url-status=dead |at=[http://www.grida.no/climate/ipcc_tar/vol4/english/025.htm Question 2, Sections 2.25 and 2.26]}}, p. 55, {{harvnb|IPCC TAR SYR|2001}}. The trend does suggest social systems are increasing vulnerable to climate change.

File:20220712 Global economic damage due to greenhouse gas emissions - by country.svg

Climate change has contributed to global economic inequality. Wealthy countries in colder regions have felt little overall economic impact from climate change or may have benefited. Poor hotter countries probably grew less than if there had been no global warming.{{Cite journal |last1=Diffenbaugh |first1=Noah S. |last2=Burke |first2=Marshall |date=2019 |title=Global warming has increased global economic inequality |journal=Proceedings of the National Academy of Sciences |volume=116 |issue=20 |pages=9808–9813 |bibcode=2019PNAS..116.9808D |doi=10.1073/pnas.1816020116 |pmc=6525504 |pmid=31010922 |doi-access=free}}{{cite book |last1=Begum |first1=Rawshan Ara |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Lempert |first2=Robert |publisher=Intergovernmental Panel on Climate Change |series=Contribution of Working Group II to the Sixth Assessment Report of the Intergovernmental Panel on Climate Change |at=Section 1.3.2.1 |chapter=Chapter 1: Point of Departure and Key Concept |display-authors=etal |access-date=5 March 2022 |chapter-url=https://report.ipcc.ch/ar6wg2/pdf/IPCC_AR6_WGII_FinalDraft_Chapter01.pdf |archive-url=https://web.archive.org/web/20220524204555/https://report.ipcc.ch/ar6wg2/pdf/IPCC_AR6_WGII_FinalDraft_Chapter01.pdf |archive-date=24 May 2022 |url-status=dead}}

Climate change has a bigger impact on economic sectors directly affected by weather than on other sectors.{{cite book |last1=Pörtner |first1=H.-O. |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Roberts |first2=D.C. |last3=Adams |first3=H. |last4=Adelekan |first4=I. |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=54 |chapter=Technical Summary |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_TechnicalSummary.pdf}} It heavily affects agriculture, fisheries and forestry.{{Cite web |title=Consequences of climate change |url=https://climate.ec.europa.eu/climate-change/consequences-climate-change_en |access-date=2023-04-15 |website=climate.ec.europa.eu |language=en}} It also affects the tourism and energy sectors. Agriculture and forestry have suffered economic losses due to droughts and extreme heat.{{cite book |last1=Pörtner |first1=H.-O. |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Roberts |first2=D.C. |last3=Adams |first3=H. |last4=Adelekan |first4=I. |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=48 |chapter=Technical Summary |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_TechnicalSummary.pdf}} If global warming goes over 1.5 °C, there may be limits to how much tourism and outdoor work can adapt.{{cite book |last1=Pörtner |first1=H.-O. |title=Climate Change 2022: Impacts, Adaptation and Vulnerability |last2=Roberts |first2=D.C. |last3=Adams |first3=H. |last4=Adelekan |first4=I. |publisher=Cambridge University Press |series=The Sixth Assessment Report of the Intergovernmental Panel on Climate Change |page=85 |chapter=Technical Summary |display-authors=etal |chapter-url=https://ipcc.ch/report/ar6/wg2/downloads/report/IPCC_AR6_WGII_TechnicalSummary.pdf}}

In the energy sector, thermal power plants depend on water to cool them. Climate change can increase the likelihood of drought and fresh water shortages. Higher operating temperatures make them less efficient. This reduces their output.Dr. Frauke Urban and Dr. Tom Mitchell 2011. [https://citeseerx.ist.psu.edu/viewdoc/download?doi=10.1.1.825.4966&rep=rep1&type=pdf Climate change, disasters and electricity generation] {{webarchive|url=https://web.archive.org/web/20120920024704/http://www.odi.org.uk/resources/details.asp?id=5792&title=climate-change-disasters-electricity-generation|date=20 September 2012}}. London: Overseas Development Institute and Institute of Development Studies Hydropower is affected by changes in the water cycle such as river flows. Diminished river flows can cause power shortages in areas that depend on hydroelectric power. Brazil relies on hydroelectricity. So it is particularly vulnerable. Rising temperatures, lower water flow, and changes in rainfall could reduce total energy production by 7% annually by the end of the century. Climate change affects oil and natural gas infrastructure. This is also vulnerable to the increased risk of disasters such as storms, cyclones, flooding and rising sea levels.{{Cite web |last1=Nichols |first1=Will |last2=Clisby |first2=Rory |title=40% of Oil and Gas Reserves Threatened by Climate Change |url=https://www.maplecroft.com/insights/analysis/40-of-oil-and-gas-reserves-threatened-by-climate-change/ |access-date=15 February 2022 |website=Verisk Maplecroft}}

Global warming affects the insurance and financial services sectors.{{rp|212–213, 228, 252}} Insurance is an important tool to manage risks. But it is often unavailable to poorer households. Due to climate change, premiums are going up for certain types of insurance, such as flood insurance. Poor adaptation to climate change further widens the gap between what people can afford and the costs of insurance, as risks increase.{{cite journal |last1=Surminski |first1=Swenja |last2=Bouwer |first2=Laurens M. |last3=Linnerooth-Bayer |first3=Joanne |date=April 2016 |title=How insurance can support climate resilience |url=http://eprints.lse.ac.uk/65672/7/Nature%20Climate%20Change%206-2016.pdf |journal=Nature Climate Change |volume=6 |issue=4 |pages=333–334 |bibcode=2016NatCC...6..333S |doi=10.1038/nclimate2979}} In 2019 Munich Re said climate change could make home insurance unaffordable for households at or below average incomes.{{cite web |last=Neslen |first=Arthur |date=21 March 2019 |title=Climate change could make insurance too expensive for most people – report |url=https://www.theguardian.com/environment/2019/mar/21/climate-change-could-make-insurance-too-expensive-for-ordinary-people-report |access-date=22 March 2019 |website=The Guardian}}

It is possible that climate change has already begun to affect the shipping sector by impacting the Panama Canal. Lack of rainfall possibly linked to climate change reduced the number of ships passing through the canal per day, from 36 to 22 and by February 2024, it is expected to be 18.{{cite news |last1=Yerushalmy |first1=Jonathan |date=22 December 2023 |title=Changing climate casts a shadow over the future of the Panama Canal – and global trade |url=https://www.theguardian.com/environment/2023/dec/22/changing-climate-casts-a-shadow-over-the-future-of-the-panama-canal-and-global-trade |access-date=28 December 2023 |agency=The Guardian}}

{{portal|Climate change|Ecology|Environment|World}}

• Anthropocene
• Climate crisis
• Extinction risk from climate change
• Extreme event attribution
• Global catastrophic risk
• History of climate change science
• List of areas depopulated due to climate change
• Politics of climate change

{{clear}}

{{reflist}}

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{{Commons category}}

• [https://www.ipcc.ch/working-group/wg1/ IPCC Working Group I (WG I)]. Intergovernmental Panel on Climate Change group which assesses the physical scientific aspects of the climate system and climate change.
• [https://web.archive.org/web/20231215221733/https://public-old.wmo.int/en/our-mandate/climate Climate] from the World Meteorological Organization
• [https://sdgs.un.org/topics/climate-change Climate change] UN Department of Economic and Social Affairs Sustainable Development
• [https://www.metoffice.gov.uk/weather/climate-change/effects-of-climate-change Effects of climate change] from the Met Office
• [https://www.unep.org/unep-and-climate-emergency United Nations Environment Programme and the climate emergency]
• [http://www.zinnedproject.org/news/climate-crisis-has-a-history/ The Climate Crisis Has a History]. Timeline by Mimi Eisen and Ursula Wolfe-Rocca.

{{Climate change|state=expanded}}

{{World topic|Climate change in|title=Climate change by country|noredlinks=yes|state=show}}

Category:Climate change and society

Glob

{{Authority control}}