vog

Vog is created when volcanic gases (primarily oxides of sulfur) react with sunlight, oxygen and moisture. The result includes sulfuric acid and other sulfates.[http://www.epa.gov/air/urbanair/so2/index.html "Sulfur Dioxide"] on US Environmental Protection Agency web site Vog is made up of a mixture of gases and aerosols which makes it hard to study and potentially more dangerous than either on their own.

Vog, which originates from volcanic vents, differs from laze, created when lava enters the ocean.[http://hilo.hawaii.edu/~nat_haz/vog/media/VogAndLazeSeminar_Abstracts_29July1991.pdf HOW VOG IS MADE: A PHOTOGRAPHIC PERSPECTIVE] {{Webarchive|url=https://web.archive.org/web/20171101215658/http://hilo.hawaii.edu/~nat_haz/vog/media/VogAndLazeSeminar_Abstracts_29July1991.pdf |date=2017-11-01 }}, Vog and Laze Seminar (July 29, 1991)

The Volcanic winter of 536 has reports of "A dense, dry fog" in the Middle East, China and Europe.{{cite book |last1=Ochoa |first1=George |title=Climate: the force that shapes our world and the future of life on earth |last2=Hoffman |first2=Jennifer |last3=Tin |first3=Tina |publisher=Rodale |year=2005 |isbn=978-1-59486-288-5 |location=Emmaus, Pennsylvania |page=71 |language=en-us}}

Image:Vog from Sulfur dioxide emissions.jpg emissions from Halemaʻumaʻu creates vog.]]

Image:Hawaiian Vog.jpg]]

In Hawaii, the gas plumes of Kīlauea rise up from three locations: Halemaʻumaʻu, Puʻu ʻŌʻō, and from along the coastline where lava flows from the East Rift zone enter the ocean. The plumes create a blanket of vog that can envelop the island. Vog mostly affects the Kona coast on the west side of the Island of Hawaii, where the prevailing trade winds blow the vog to the southwest and southern winds then blow it north up the Kohala coast.

Prolonged periods of southerly Kona winds, however, can cause vog to affect the eastern side of the Island on rare occasions, and affect islands across the entire state as well.[http://hvo.wr.usgs.gov/volcanowatch/1996/96_05_29.html "Vog: A Volcanic Hazard"] on USGS web site By the time the vog reaches other islands, the sulfur dioxide has largely dissipated, leaving behind ash, smoke, sulfates, and ammonia.{{Cite web |url=http://www.mauiweekly.com/page/content.detail/id/9344/Vog-Taints-Maui-Skies.html |title=Vog Taints Maui Skies |access-date=2009-12-29 |archive-url=https://web.archive.org/web/20110321000537/http://www.mauiweekly.com/page/content.detail/id/9344/Vog-Taints-Maui-Skies.html |archive-date=2011-03-21 |url-status=dead }}

During the 2016 volcanic events at Kīlauea, the Hawaiian Volcano Observatory, in collaboration with other agencies, published a vog dashboard so community members could track the vog.{{Cite web |last=Ozawa |first=Ryan |date=2016-08-26 |title=Civil Geeks: Feeling The Vog? This Tool Can Help You Deal |url=https://www.civilbeat.org/2016/08/civil-geeks-feeling-voggy-theres-a-website-for-that/ |access-date=2023-06-01 |website=Honolulu Civil Beat |language=en}}

{{unreferenced section|date=August 2021}}

Vog and smog are different. Vog is formed when sulfur oxides emitted by a volcano react with moisture to form an aerosol. The aerosol scatters light, thus making the vog visible. Smog is formed largely from the incomplete combustion of fuel, reacting with nitrogen oxides and ozone produced from carbon monoxide by reactions with sunlight. The result is also a visible aerosol.

When smog levels are high, the sky appears yellowish-grey because nitrogen oxides are yellow. In contrast, sulfur oxides are colorless and vog looks grey. Once the vog layer dissipates, grey spots of vog in the sky may, for a time, remain trapped in the inversion layer.

Several chemicals emitted from cars are not emitted from volcanoes. Similarly, some chemicals emitted from volcanoes, such as hydrogen sulfide, hydrogen chloride, and hydrogen fluoride, are not created by exhaust gas. Moreover, smog generated by factories has its own unique mix of contaminants.{{citation needed|date=August 2019}}

Image:Vog sunset in Kona.jpg created a strangely shaped sun in this sunset.]]

Most studies of vog have been in areas where vog is naturally present and not in controlled conditions. Vog contains chemicals that can damage the environment and the health of plants, humans and other animals. Most of the aerosols are acidic and of a size where they can remain in the lungs to damage the lungs and impair function. Headaches, watery eyes, sore throat, breathing difficulties (including inducing asthma attacks), flu-like symptoms and general lethargy are commonly reported. These effects are especially pronounced in children and in people with respiratory conditions. Vog generally reduces visibility, creating a hazard for road, air and ocean traffic.

The long-term health effects of vog are unknown.

Several studies are underway to measure the air quality near volcanoes more carefully.[http://airnow.gov/index.cfm?action=airnow.fcsummary&stateid=15 Hawaii Air Quality Conditions & Forecasts] {{Webarchive|url=https://web.archive.org/web/20150705222938/http://airnow.gov/index.cfm?action=airnow.fcsummary&stateid=15 |date=2015-07-05 }} on "Airnow" US Government web site

Sulfur dioxide emissions increased on March 12, 2008, when a new vent opened. The increased vog level has caused evacuations and damaged crops. In the summer of 2008 and in 2012, the County of Hawai{{okina}}i received a disaster designation due to the agricultural damage.[http://hawaii.gov/gov/vog "Vog: Important Information and Facts" ] on State of Hawaii Office of the Governor web site

A recent multi-year computer-modeling feasibility study, known as VMAP, designed to predict the location and concentrations of vog from Kīlauea was conducted by the University of Hawaii.{{cite journal | title=Observing and Forecasting Vog Dispersion from Kīlauea Volcano, Hawaii | journal=Bulletin of the American Meteorological Society | year=2015 | volume=96 |issue = 10| pages=1667–1686 | doi=10.1175/BAMS-D-14-00150.1| bibcode=2015BAMS...96.1667B | doi-access=free | last1=Horton | first1=Keith | last2=Pattantyus | first2=Andre | last3=Huff | first3=Roy | last4=Businger | first4=Steven | last5=Sutton | first5=A. Jeff | last6=Elias | first6=Tamar | last7=Cherubini | first7=Tiziana }}

• Laze
• Mist Hardships

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{{Wiktionary}}

• [http://earthobservatory.nasa.gov/IOTD/view.php?id=38709&src=eoa-iotd Hawaiian vog photographed from Space Shuttle]
• [https://www.youtube.com/watch?v=x6zukeZ7aEg Video of vog in Hawaii]
• [https://www.cdc.gov/niosh/docs/2005-100/ National Institute for Occupational Safety and Health Respirator Selection Logic]
• [https://vog.ivhhn.org/ Hawaii Interagency Vog Information Dashboard]

Category:Smog

Category:Volcanism

Category:Weather events in Hawaii

Category:Volcanic degassing