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Alpine Lake
Alpine lakes are classified as lakes at high altitudes in mountainous zones, usually near or above the tree line, with extended periods of ice cover. These lakes are commonly formed from glacial activity (either current or in the past) but can also be formed from geological processes such as volcanic activity or landslides. Many alpine lakes that are fed from glacial melt have the characteristic bright turquoise or green color as a result of glacial flour, suspended minerals derived from a glacier scouring the bedrock. When active glaciers are not supplying water to the lake, such as a majority of alpine lakes of the Rocky Mountains in the U.S., the lakes may still be bright blue due to the lack of algae growth resulting from cold temperatures, lack of nutrient run-off from surrounding land, and lack of sediment input. The coloration and mountain locations of alpine lakes attract lots of recreational activity. Alpine lakes are some of the most abundant types of lakes on Earth. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blanca Lake Hudak
Blanca (meaning "white" in Spanish) may refer to: Locations United States * Casa Blanca, California or Blanca, a former unincorporated community * Blanca, Colorado, a Statutory Town *Blanca Peak, a mountain in Colorado * Blanca Wetlands, a protected area in Colorado *La Blanca, Texas, a census-designated place *one of many early names of Galveston Island, Texas - see History of Galveston, Texas *Blanca Lake, a lake in Washington Elsewhere *La Blanca, an archeological site in Guatemala *Blanca, Sevnica, a settlement in Slovenia * Blanca, Murcia, a town in Spain * Isla Blanca (other) People * Blanca (given name) * Nida Blanca (1936–2001), Filipina actress * Blanca (musician), a contemporary Christian music artist Other uses * ''Blanca'' (album), by Christian musician Blanca * ''Blanca'', a 1971 film by Walerian Borowczyk See also * Blanco (other) * Blanch (other) * Blanche (other) * Blanka (other) *Hurricane Blanca The name Blanca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cirque
A (; from the Latin word ') is an amphitheatre-like valley formed by glacial erosion. Alternative names for this landform are corrie (from Scottish Gaelic , meaning a pot or cauldron) and (; ). A cirque may also be a similarly shaped landform arising from fluvial erosion. The concave shape of a glacial cirque is open on the downhill side, while the cupped section is generally steep. Cliff-like slopes, down which ice and glaciated debris combine and converge, form the three or more higher sides. The floor of the cirque ends up bowl-shaped, as it is the complex convergence zone of combining ice flows from multiple directions and their accompanying rock burdens. Hence, it experiences somewhat greater erosion forces and is most often overdeepened below the level of the cirque's low-side outlet (stage) and its down-slope (backstage) valley. If the cirque is subject to seasonal melting, the floor of the cirque most often forms a tarn (small lake) behind a dam, which marks the d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meromictic Lake
A meromictic lake is a lake which has layers of water that do not intermix. In ordinary, holomictic lakes, at least once each year, there is a physical mixing of the surface and the deep waters. The term ''meromictic'' was coined by the Austrian Ingo Findenegg in 1935, apparently based on the older word ''holomictic''. The concepts and terminology used in describing meromictic lakes were essentially complete following some additions by G. Evelyn Hutchinson in 1937. Characteristics Most lakes are ''holomictic''; that is, at least once per year, physical mixing occurs between the surface and the deep waters. In so-called monomictic lakes, the mixing occurs once per year; in dimictic lakes, the mixing occurs twice a year (typically spring and autumn), and in polymictic lakes, the mixing occurs several times a year. In meromictic lakes, however, the layers of the lake water can remain unmixed for years, decades, or centuries. Meromictic lakes can usually be divided into t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polymictic Lake
Polymictic lakes are holomictic lakes that are too shallow to develop thermal stratification; thus, their waters can mix from top to bottom throughout the ice-free period. Polymictic lakes can be divided into cold polymictic lakes (i.e., those that are ice-covered in winter), and warm polymictic lakes (i.e., polymictic lakes in regions where ice-cover does not develop in winter). While such lakes are well-mixed on average, during low-wind periods, weak and ephemeral stratification can often develop. See also * Amictic lake * Holomictic lake * Meromictic lake * Monomictic lake * Dimictic lake * Thermocline A thermocline (also known as the thermal layer or the metalimnion in lakes) is a thin but distinct layer in a large body of fluid (e.g. water, as in an ocean or lake; or air, e.g. an atmosphere) in which temperature changes more drastically with ... * References External links "Circulation: annual patterns of dimictic lakes" at Encyclopædia Britannica Online Lakes by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dimictic Lake
A dimictic lake is a body of freshwater whose difference in temperature between surface and bottom layers becomes negligible twice per year, allowing all strata of the lake's water to circulate vertically. All dimictic lakes are also considered holomictic, a category which includes all lakes which mix one or more times per year. During winter, dimictic lakes are covered by a layer of ice, creating a cold layer at the surface, a slightly warmer layer beneath the ice, and a still-warmer unfrozen bottom layer, while during summer, the same temperature-derived density differences separate the warm surface waters (the epilimnion), from the colder bottom waters (the hypolimnion). In the spring and fall, these temperature differences briefly disappear, and the body of water overturns and circulates from top to bottom. Such lakes are common in mid-latitude regions with temperate climates. Examples of dimictic lakes * Lake Mendota * Lake Superior * Lake Simcoe * Lake Opeongo * Loch Lo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Stratification
Lake stratification is the tendency of lakes to form separate and distinct thermal layers during warm weather. Typically stratified lakes show three distinct layers, the Epilimnion comprising the top warm layer, the thermocline (or Metalimnion): the middle layer, which may change depth throughout the day, and the colder Hypolimnion extending to the floor of the lake. Definition The thermal stratification of lakes refers to a change in the temperature at different depths in the lake, and is due to the density of water varying with temperature. Cold water is denser than warm water and the epilimnion generally consists of water that is not as dense as the water in the hypolimnion. However, the temperature of maximum density for freshwater is 4 °C. In temperate regions where lake water warms up and cools through the seasons, a cyclical pattern of overturn occurs that is repeated from year to year as the cold dense water at the top of the lake sinks (see stable and unstable s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lago Di Cadagno
__NOTOC__ Lake Cadagno (Italian: ''Lago di Cadagno'') is a meromictic lake in the Piora valley (canton of Ticino), Switzerland. As one of a few meromictic lakes in Europe, it is the object of numerous scientific studies. The Piora valley - located in the Saint-Gotthard Massif (central Swiss Alps) in the Southern part of Switzerland near Airolo at an altitude of 1921 m above sea level - is a landlocked alpine valley whose scientific value has been recognized for more than two centuries. In the past, the lake was used as a reservoir. Lake Cadagno is a rare example of crenogenic meromixis. Its waters show a permanent stratification due to a natural geological phenomenon. The lower abounds with dissolved mineral salts (sulphate, magnesium, calcium, carbonate) originating from sublacustrine springs, whereas the separate upper layer is permanently oxygenated. Anaerobic phototrophic bacteria – among them ''Chromatium okenii''—thrive between the two layers where they find the ideal co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lake Louise, Alberta
Lake Louise is a hamlet within Banff National Park in Alberta, Canada. Named after Princess Louise, Duchess of Argyll, it lies in Alberta's Rockies on the Bow River, northeast of the lake that shares its name. Initially settled in 1884 as an outpost for the Canadian Pacific Railway, Lake Louise sits at an elevation of , making it Canada's highest community. The nearby lake, framed by mountains, is one of the most famous mountain vistas in the world; the famous Chateau Lake Louise also overlooks the lake. History Prior to the arrival of Europeans, Indigenous peoples lived in the foothills and forests of the Rocky Mountains - including what is today Lake Louise, where they hunted bison and other big game animals. In the Stoney language of the Nakoda people the area is called , meaning "lake of the little fishes". During the 1870s, the construction of the Canadian Pacific Railway (CPR) started. The railway was planned to run through Bow Valley. A Nakoda guide took CPR workm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laurentide Ice Sheet
The Laurentide Ice Sheet was a massive sheet of ice that covered millions of square miles, including most of Canada and a large portion of the Northern United States, multiple times during the Quaternary glacial epochs, from 2.58 million years ago to the present. The last advance covered most of northern North America between c. 95,000 and c. 20,000 years before the present day and, among other geomorphological effects, gouged out the five Great Lakes and the hosts of smaller lakes of the Canadian Shield. These lakes extend from the eastern Northwest Territories, through most of northern Canada, and the upper Midwestern United States (Minnesota, Wisconsin, and Michigan) to the Finger Lakes, through Lake Champlain and Lake George areas of New York, across the northern Appalachians into and through all of New England and Nova Scotia. At times, the ice sheet's southern margin included the present-day sites of coastal towns of the Northeastern United States, and cities suc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Worm Glacier
Ice is water frozen into a solid state, typically forming at or below temperatures of 0 degrees Celsius or Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color. In the Solar System, ice is abundant and occurs naturally from as close to the Sun as Mercury to as far away as the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice. It is abundant on Earth's surfaceparticularly in the polar regions and above the snow lineand, as a common form of precipitation and deposition, plays a key role in Earth's water cycle and climate. It falls as snowflakes and hail or occurs as frost, icicles or ice spikes and aggregates from snow as glaciers and ice sheets. Ice exhibits at least eighteen phases ( packing geometries), depending on temperature and pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form depending on it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Climate Change
In common usage, climate change describes global warming—the ongoing increase in global average temperature—and its effects on Earth's climate system. Climate change in a broader sense also includes previous long-term changes to Earth's climate. The current rise in global average temperature is more rapid than previous changes, and is primarily caused by humans burning fossil fuels. Fossil fuel use, deforestation, and some agricultural and industrial practices increase greenhouse gases, notably carbon dioxide and methane. Greenhouse gases absorb some of the heat that the Earth radiates after it warms from sunlight. Larger amounts of these gases trap more heat in Earth's lower atmosphere, causing global warming. Due to climate change, deserts are expanding, while heat waves and wildfires are becoming more common. Increased warming in the Arctic has contributed to melting permafrost, glacial retreat and sea ice loss. Higher temperatures are also causing ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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