Vättern

{{Infobox body of water

|name = Vättern

|image = A_distant_memory_(2835767026).jpg

|caption = West-to-east view of the lake including Visingsö in the foreground

|alt=Photograph

|image_size = 250

|image_bathymetry =

|caption_bathymetry =

|pushpin_map = Sweden

|pushpin_map_alt = Location of Vättern

|coords = {{Coord|58|24|N|14|36|E|region:SE_type:waterbody_scale:2000000|display=inline,title}}

|type =

|inflow =

|outflow = Motala ström

|catchment = {{convert|4503|km2|abbr=on}}

|basin_countries = Sweden

|length =

|width =

|area = {{convert|1912|km2|abbr=on}}

|depth = {{convert|41|m|abbr=on}}

|max-depth = {{convert|128|m|abbr=on}}

|volume = {{convert|77.0|km3|abbr=on}}

|residence_time =

|shore =

|elevation = {{convert|88|m|abbr=on}}

|islands = Visingsö

|cities = Vadstena, Jönköping, Hjo, Askersund, Åmmeberg, Karlsborg, Motala

|reference = {{Cite book |last=Seppälä |first=Matti |author-link=Matti Seppälä |title=The Physical Geography of Fennoscandia |url=https://books.google.com/books?id=q33WekTp7tgC&pg=PA145 |publisher=Oxford University Press |year=2005 |isbn=978-0-19-924590-1 |page=145}}

}}

Vättern ({{IPAc-en|ˈ|v|ɛ|t|ər|n}} {{respell|VET|ərn}},{{Cite American Heritage Dictionary |Vättern |access-date=14 April 2019}}[https://web.archive.org/web/20190414111009/https://en.oxforddictionaries.com/definition/us/V%25C3%25A4ttern "Vättern"] (US) and {{Cite dictionary |url=http://www.lexico.com/definition/V%C3%A4ttern |title=Vättern |dictionary=Oxford Dictionaries UK English Dictionary |publisher=Oxford University Press}}{{dead link|date=September 2022|bot=medic}}{{cbignore|bot=medic}}{{Cite Merriam-Webster |Vättern |access-date=14 April 2019}} {{IPA|sv|ˈvɛ̌tːɛɳ|lang}}) is the second-largest lake in Sweden, after Vänern, and the sixth-largest lake in Europe. It is a long, finger-shaped body of fresh water in south central Sweden, to the southeast of Vänern, pointing at the tip of Scandinavia. Vättern is deep, containing roughly half as much water as Vänern even though it covers about a third as much area; its deepest point is {{convert|128|m|ft}} below sea level.

Vättern drains into Motala ström through Bråviken into the Baltic Sea, but since 1832 it has also had a downstream connection through the Göta Canal to Vänern and the Kattegat tributary of the Atlantic Ocean. The lake has plenty of sources from rivers and small lakes, with the highest located sources being near Nässjö on the South Swedish Highland near the southeastern shoreline.

Name

The name Vättern is closely related to "vatten", the Swedish word for water, and also means "water, lake".{{cite book |title=Svenskt ortnamnslexikon |year=2003 |publisher=Språk- och folkminnesinstitutet (SOFI) |location=Uppsala |isbn=91-7229-020-X |chapter=Vättern}}

Geography

File:Vättern by Sentinel-2.jpg

The lake's total surface area is about {{convert|1912|km2|abbr=on}}, with a drainage basin a little over double that, about {{convert|4503|km2|abbr=on}}. The deepest known point, located to the south of the island of Visingsö, is {{convert|128|m|sp=us}}. The average depth is {{convert|41|m|sp=us}}. The lake has a perimeter of about {{convert|642|km|abbr=on}}. The volume is {{convert|77.0|km3|abbr=on}}. These numbers tend to be fixed, as the level of the lake is regulated.

Situated in Götaland, the lake is drained by Motala ström, starting at Motala, and flowing ultimately through a controlled canal into the Baltic Sea. The lake includes the scenic island of Visingsö, located outside Gränna. Other towns on the lake include Vadstena, Jönköping, Hjo, Askersund, Åmmeberg and Karlsborg. It is bounded by the Provinces of Västergötland, Närke, Östergötland and Småland.

In the north there is a scenic but not mountainous inland fjord, Alsen. About 62% of the drainage basin is still covered with spruce, pine and deciduous forest. About 26.7% is dedicated to agriculture.

Geology

While many of smaller lakes in southern Sweden are thought to have originated by glacial stripping of an irregular weathering mantle in the last 2.5 million years{{cite book |last1=Lidmar-Bergström |first1=K. |last2=Olsson |first2=S. |last3=Roaldset |first3=E. |author-link1=Karna Lidmar-Bergström |date=1999 |chapter=Relief features and palaeoweathering remnants in formerly glaciated Scandinavian basement areas |title=Palaeoweathering, Palaeosurfaces and Related Continental Deposits |editor-last1=Thiry |editor-first1=Médard |editor-last2=Simon-Coinçon |editor-first2=Régine |publisher=Blackwell Science Ltd |pages=275–301 |isbn=0-632-05311-9 |volume=27 |series=Special publication of the International Association of Sedimentologists }} Vättern formed by tectonics as a graben 700 to 800 million years ago in the Neoproterozoic.{{cite journal |title=Major earthquake at the Pleistocene-Holocene transition in Lake Vättern, southern Sweden |first1=M. |last1=Jakobsson |first2=S. |last2=Björck |first3=M. |last3=O'Regan |first4=T. |last4=Flodén |first5=S. L. |last5=Greenwood |first6=H. |last6=Swärd |first7=A. |last7=Lif |first8=L. |last8=Ampel |first9=H. |last9=Koyi |first10=A. |last10=Skelton |journal=Geology |year=2014 |volume=42 |issue=5 |pages=379–382 |doi=10.1130/G35499.1 |doi-access=free }} Granitic basement rocks in the lake are deformed (foliated) by the Protogine Zone that crosses the area. The basin is partially filled by sedimentary rock of the Visingsö Group of Neoproterozoic age. This group include rocks such as conglomerate, sandstone, arkose and carbonates. The older of these sediments deposited before the Vättern came into existence as a graben.{{cite journal |last1=Wikström |first1=Anders |last2=Karis |first2=Lars |date=1993 |title=Note on the basement-cover relationship of the Visingsö group in the northern part of the Lake Vättern basin, south Sweden |journal=GFF |volume=115 |issue=4 |pages=311–313 |doi=10.1080/11035899309453918 }} Acritarch microfossils such as Chuaria circularis are common in Visingsö Group.{{cite journal |last1=Talyzina |first1=Nina M. |date=2000 |title=Ultrastructure and morphology of Chuaria circularis (Walcott, 1899) Vidal and Ford (1985) from the Neoproterozoic Visingsö Group, Sweden |url=https://pdfs.semanticscholar.org/ffbc/542095fca4b65b7f6d7c41eb87de4c8ee786.pdf |archive-url=https://web.archive.org/web/20180122071911/https://pdfs.semanticscholar.org/ffbc/542095fca4b65b7f6d7c41eb87de4c8ee786.pdf |url-status=dead |archive-date=2018-01-22 |journal=Precambrian Research |volume=102 |issue=1–2 |pages=123–134 |doi=10.1016/S0301-9268(00)00062-0 |bibcode=2000PreR..102..123T |s2cid=38532660 }}

During the most recent millions of years multiple glaciations have covered the lake and its surroundings, leaving glacial striations and drumlins as they receded.

The present-day lake began as an independent body of water left by the receding Scandinavian glacier after the last glacial period around 10,000 BP. It became a minor bay of the Baltic ice lake. Most of the lake's relict species (like the Arctic char) date from that time. Subsequently, it was a bay of Yoldia Sea and then became connected to Ancylus Lake, discharging from the north end of its extent. At about 8000 BP an accident of the uneven Scandinavian isostatic land rise brought Vättern above Ancylus and the two became distinct.

The annual post-glacial rebound today is {{convert|3.5|mm|abbr=on}} in northeastern Motala and {{convert|2.6|mm|abbr=on}} in southern Jönköping. This means that Vättern is tilting to the south by {{convert|1|mm|abbr=on}} every year.{{cite web |title=Fakta om Vättern |language=sv |url=http://www.lansstyrelsen.se/jonkoping/projektwebbar/fiskaivattern/Fakta+om+Vattern/ |url-status=dead |archive-url=https://web.archive.org/web/20090806212311/http://www.lansstyrelsen.se/jonkoping/projektwebbar/fiskaivattern/Fakta+om+Vattern/ |archive-date=6 August 2009 }}

Biology

The lake contains both phytoplankton and zooplankton, such as Copepoda and Cladocera. The benthos species include Crustacea, Oligochaeta, Diptera and Bivalvia. In addition are several species of fish, including Salvelinus salvelinus, Coregonus lavaretus and Salmo salar. The lake is known for its Vättern char, as it is called, Salvelinus alpinus.{{cite web

|title = "Fakta om Fisk, fiske och Fiskevård". A four page brochure from Sweden's Fishing Institute

|url = http://www.fiskeriverket.se/publikationer/f-fakta/pdf/f-fakta16-04_web.pdf

|language = sv

|access-date = 2005-11-02

|archive-url = https://web.archive.org/web/20060526102118/http://www.fiskeriverket.se/publikationer/f-fakta/pdf/f-fakta16-04_web.pdf

|archive-date = 2006-05-26

|url-status = dead

}} The Vättern char is genetically close to the Sommen char in nearby Lake Sommen and chars of Lake Ladoga in Russia.{{cite journal |last1=Hammar |first1=J. |date=2014 |title=Natural resilience in Arctic charr Salvelinus alpinus: life history, spatial and dietary alterations along gradients of interspecific interactions |journal=Fish Biology |volume=85 |issue=1 |pages=81–118 |doi=10.1111/jfb.12321 |pmid=24754706 }}

Uses

=The lake=

Vättern has been famous for the excellent quality of its transparent water. Many of the municipalities in the area receive their drinking water directly from Vättern. The lake water requires very little treatment before being pumped into the municipal systems and the natural, untreated water can be safely drunk from almost any point in the lake. It has been suggested that Vättern is the largest body of potable water in the world. The surrounding municipalities process 100% of their sewage.

Vättern is known for the annual recreational cycling race Vätternrundan, attracting some 20,000 participants to finish the 300 km trip around the shores of the lake.

Vättern is also noted for its fishing, serving people in the nearby districts. Tourist sport fishermen and vacationers are free to fish in the lake as long as they don't use nets. The lake is also used for commercial fishing.

=The drainage basin=

A number of industries provide employment in the drainage basin: mining, manufacturing, forestry and paper. Agriculturalists raise cattle, sheep, swine and poultry.

=Cultural notes=

According to the Catholic Church, Saint Catherine of Vadstena performed a miracle involving three people in peril on lake ice.{{Cite web |url=https://wikihost.uib.no/medieval/index.php/Sancta_Katherina |title=Medieval Nordic Literature in Latin: Sancta Katherina |access-date=2012-10-09 |archive-date=2016-08-16 |archive-url=https://web.archive.org/web/20160816141416/https://wikihost.uib.no/medieval/index.php/Sancta_Katherina |url-status=dead }}

Thomas Nashe mentions this lake (Lake Vether) in his Terrors of the NightNashe, Thomas. Ed. J.B. Steane. The Unfortunate Traveller and Other Works. Penguin, 1972, p. 223. (published 1594), although he mistakenly locates the lake in Iceland:

Admirable, above the rest, are the incomprehensible wonders of the bottomless Lake Vether, over which no fowl flies but is frozen to death, nor any man passeth but he is senselessly benumbed like a statue of marble.

All the inhabitants round about it are deafened with the hideous roaring of his waters when the winter breaketh up, and the ice in his dissolving gives a terrible crack like to thunder, whenas out of the midst of it, as out of Mont-Gibell, a sulphureous stinking smoke issues, that wellnigh poisons the whole country.

Lake Vether is also mentioned in Samuel Johnson's essay for The Idler No. 96, on Hacho of Lapland.

John Bauer, his wife Ester and their three-year-old son, Bengt, drowned in the sinking in bad weather of the steamer Per Brahe on the lake on the night 19 November 1918.