Portal:Lakes
The Lakes Portal
A portal dedicated to Lakes
Introduction
A lake is an area filled with water, localized in a basin, surrounded by land, apart from any river or other outlet that serves to feed or drain the lake. Lakes lie on land and are not part of the ocean, although like the much larger oceans, they form part of earth's water cycle. Lakes are distinct from lagoons which are generally coastal parts of the ocean. They are generally larger and deeper than ponds, which also lie on land, though there are no official or scientific definitions. Lakes can be contrasted with rivers or streams, which are usually flowing in a channel on land. Most lakes are fed and drained by rivers and streams.
Natural lakes are generally found in mountainous areas, rift zones, and areas with ongoing glaciation. Other lakes are found in endorheic basins or along the courses of mature rivers, where a river channel has widened into a basin. In some parts of the world there are many lakes because of chaotic drainage patterns left over from the last Ice Age. All lakes are temporary over geologic time scales, as they will slowly fill in with sediments or spill out of the basin containing them.
Many lakes are artificial and are constructed for industrial or agricultural use, for hydro-electric power generation or domestic water supply, or for aesthetic, recreational purposes, or other activities. (Full article...)
Selected article -
A subglacial lake is a lake that is found under a glacier, typically beneath an ice cap or ice sheet. Subglacial lakes form at the boundary between ice and the underlying bedrock, where gravitational pressure decreases the pressure melting point of ice. Over time, the overlying ice gradually melts at a rate of a few millimeters per year. Meltwater flows from regions of high to low hydraulic pressure under the ice and pools, creating a body of liquid water that can be isolated from the external environment for millions of years.
Since the first discoveries of subglacial lakes under the Antarctic Ice Sheet, more than 400 subglacial lakes have been discovered in Antarctica, beneath the Greenland Ice Sheet, and under Iceland's Vatnajökull ice cap. Subglacial lakes contain a substantial proportion of Earth's liquid freshwater, with the volume of Antarctic subglacial lakes alone estimated to be about 10,000 km3, or about 15% of all liquid freshwater on Earth.
As ecosystems isolated from Earth's atmosphere, subglacial lakes are influenced by interactions between ice, water, sediments, and organisms. They contain active biological communities of extremophilic microbes that are adapted to cold, low-nutrient conditions and facilitate biogeochemical cycles independent of energy inputs from the sun. Subglacial lakes and their inhabitants are of particular interest in the field of astrobiology and the search for extraterrestrial life. (Full article...)General topics
Need assistance?
Do you have a question about lakes that you can't find the answer to? Consider asking it at the Wikipedia reference desk.
General images
Lava lake at Mount Nyiragongo in the Democratic Republic of the Congo
A schematic cross-section of the subglacial pool beneath Taylor Glacier and its outflow, Blood Falls. Image credit: Zina Deretsky / US National Science Foundation
Badwater Basin dry lake, 15 February 2007. Landsat 5 satellite photo
Lake Kaniere is a glacial lake in the West Coast region of New Zealand.
Lake Sevan is the largest body of water in Armenia and the Caucasus region. It is one of the largest freshwater high-altitude (alpine) lakes in Eurasia
Lake Mapourika, New Zealand
Russian scientist Peter Kropotkin first proposed the idea of fresh water under Antarctic ice.
Soda Lakes in Nevada, USA
The first view of the sediment at the bottom of subglacial Lake Whillans, captured by the WISSARD expedition. Image credit: NASA/JPL, California Institute of Technology
These kettle lakes in Alaska were formed by a retreating glacier
A view of the southern polar plain of Mars. The area where a subglacial lake has been detected is highlighted. Image credit: USGS Astrogeology Science Center, Arizona State University
Garibaldi Lake in British Columbia, Canada, is impounded by lava flows comprising The Barrier
Lake of Flowers (Liqeni i Lulëve), one of the Lurë Mountains glacial lakes, Albania
The Caspian Sea is either the world's largest lake or a full-fledged sea
Lake Tahoe on the border of California and Nevada
Crater Lake in Oregon, USA
Heaven Lake, the crater lake of Paektu Mountain on the China–North Korea border
Ephemeral 'Lake Badwater', a lake only noted after heavy winter and spring rainfall, Badwater Basin, Death Valley National Park, 9 February 2005. Landsat 5 satellite photo
Lake zones (left) and algal communities (right)
There are some 187,888 lakes in Finland larger than 500 square metres. Isojärvi is the 97th largest lake in Finland.
An artist's depiction of the subglacial lakes and rivers beneath the Antarctic Ice Sheet. Image credit: Zina Deretsky / US National Science Foundation
Oeschinen Lake in the Swiss Alps
Titan's north polar hydrocarbon seas and lakes as seen in a false-color Cassini synthetic aperture radar mosaic
The crater lake of Volcán Irazú, Costa Rica
Ice Melting on Lake Balaton
Round Tangle Lake, one of the Tangle Lakes, 2,864 feet (873 m) above sea level in interior Alaska
The Seven Rila Lakes are a group of glacial lakes in the Bulgarian Rila mountains
An illustration of ice core drilling above subglacial Lake Vostok. These drilling efforts collected re-frozen lake water that has been analyzed to understand the lake's chemistry. Image credit: Nicolle Rager-Fuller / US National Science Foundation
Satellite image of subglacial Lake Vostok in Antarctica. Image credit: NASA
_and_algal_communities_(right).jpg)
.jpg)
Related portals
WikiProjects
Categories
More articles
Associated Wikimedia
External media
- World Lake Database. International Lake Environment Committee Foundation. – provides a searchable database
- Global Lakes and Wetlands Database. World Wide Fund for Nature. – available for free download
Portals