|
Antarctic Dry Valleys
The McMurdo Dry Valleys are a row of largely Antarctic oasis, snow-free valleys in Antarctica, located within Victoria Land west of McMurdo Sound. The Dry Valleys experience extremely low humidity and surrounding mountains prevent the flow of ice from nearby glaciers. The rocks here are granites and gneisses, and glacial tills dot this bedrock landscape, with loose gravel covering the ground. It is one of the driest places on Earth and has not seen rain for nearly two million years. The region is one of the world's most extreme deserts, and includes many features including Lake Vida, a saline lake, and the Onyx River, a meltwater stream and Antarctica's longest river. Although no living organisms have been found in the permafrost here, Endolithic lichen, endolithic Photosynthesis, photosynthetic bacteria have been found living in the relatively moist interior of rocks, and anaerobic bacteria, with a metabolism based on iron and sulfur, live under the Taylor Glacier. The valle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mcmurdo Sound USGS Map
Vice-Admiral Archibald McMurdo (24 September 1812 – 11 December 1875) was a Scottish naval officer and polar explorer after whom Antarctica's McMurdo Sound, McMurdo Station, McMurdo Ice Shelf, McMurdo Dry Valleys and McMurdo–South Pole Highway are named. Early life Archibald William McMurdo was born on September 24, 1812 in Scotland. He was the son of Lieutenant Colonel Archibald McMurdo and grandson of John McMurdo, a chamberlain at Drumlanrig Castle. Career McMurdo joined the Royal Navy on 6 October 1824, at the age of 12. He was promoted to Lieutenant in 1836 for his skill and courage in saving the crew of a shipwrecked whaler from hostile New Zealand natives. He achieved the rank of Commander in 1843 and Captain in 1851. His career included two discovery expeditions aboard HMS ''Terror'', the first to Hudson Bay (1836-1837), the second to Antarctica (1839-1842). In 1836 he served on HMS Volage during its voyage to East India. During the Antarctica voyage, McMurdo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
River
A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of water. Small rivers can be referred to using names such as Stream#Creek, creek, Stream#Brook, brook, rivulet, and rill. There are no official definitions for the generic term river as applied to Geographical feature, geographic features, although in some countries or communities a stream is defined by its size. Many names for small rivers are specific to geographic location; examples are "run" in some parts of the United States, "Burn (landform), burn" in Scotland and northeast England, and "beck" in northern England. Sometimes a river is defined as being larger than a creek, but not always: the language is vague. Rivers are part of the water cycle. Water generally collects in a river from Precipitation (meteorology), precipitation through a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctic, Antarctic, And Alpine Research
''Arctic, Antarctic, and Alpine Research'' is a peer-reviewed scientific journal published by the Institute of Arctic and Alpine Research (University of Colorado Boulder). It covers research on all aspects of Arctic, Antarctic, and alpine environments, including subarctic, subantarctic, subalpine, and paleoenvironments. Jack D. Ives founded the journal in 1969 as ''Arctic and Alpine Research'' and the name was expanded to include the Antarctic in 1999. The editors-in-chief are Anne E. Jennings and Bill Bowman (University of Colorado Boulder). Abstracting and indexing The journal is abstracted and indexed in the Science Citation Index, Current Contents/Agriculture, Biology & Environmental Sciences, The Zoological Record, and BIOSIS Previews. According to the ''Journal Citation Reports'', the journal has a 2017 impact factor The impact factor (IF) or journal impact factor (JIF) of an academic journal is a scientometric index calculated by Clarivate that reflects the yearly me ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ice Wedge
An ice wedge is a crack in the ground formed by a narrow or thin piece of ice that measures up to 3–4 meters in length at ground level and extends downwards into the ground up to several meters. During the winter months, the water in the ground freezes and expands. Once temperatures reach −17 degrees Celsius or lower, the ice that has already formed acts like a solid and expands to form cracks in the surface known as ice wedges. As this process continues over many years ice wedges can grow, up to the size of a swimming pool. Ice wedges usually appear in a polygonal pattern known as ice wedge polygons. The cracks can also be filled with materials other than ice, especially sand, and are then called sand wedges. Formation There are many theories that attempt to explain the origin of ice wedges but only one has been consistently supported by most prominent scientists: the thermal contraction theory. Thermal contraction theory The thermal contraction theory posits that during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ross Sea
The Ross Sea is a deep bay of the Southern Ocean in Antarctica, between Victoria Land and Marie Byrd Land and within the Ross Embayment, and is the southernmost sea on Earth. It derives its name from the British explorer James Clark Ross who visited this area in 1841. To the west of the sea lies Ross Island and Victoria Land, to the east Roosevelt Island and Edward VII Peninsula in Marie Byrd Land, while the southernmost part is covered by the Ross Ice Shelf, and is about from the South Pole. Its boundaries and area have been defined by the New Zealand National Institute of Water and Atmospheric Research as having an area of . The circulation of the Ross Sea is dominated by a wind-driven ocean gyre and the flow is strongly influenced by three submarine ridges that run from southwest to northeast. The circumpolar deep water current is a relatively warm, salty and nutrient-rich water mass that flows onto the continental shelf at certain locations. The Ross Sea is covered with ice ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
East Antarctic Ice Sheet
The East Antarctic Ice Sheet (EAIS) is one of two large ice sheets in Antarctica, and the largest on the entire planet. The EAIS lies between 45° west and 168° east longitudinally. The EAIS holds enough ice to raise global sea levels by and is considerably larger in area and mass than the West Antarctic Ice Sheet (WAIS). It is separated from the WAIS by the Transantarctic Mountains. The EAIS is the driest, windiest, and coldest place on Earth, with temperatures reported down to nearly -100°C. The EAIS holds the thickest ice on Earth, at . It is home to the geographic South Pole and the Amundsen–Scott South Pole Station. Temperature changes Cooling in East Antarctica during the decades of the 1980s and 1990s partially offset the impact of climate change on the West Antarctic Ice Sheet, which has warmed by more than 0.1 °C/decade in the last 50 years. The continent-wide average surface temperature trend of Antarctica is positive and statistically significant at >0.0 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secretariat Of The Antarctic Treaty
__NOTOC__ The Antarctic Treaty Secretariat (ATS) is a subsidiary body of the Antarctic Treaty Consultative Meeting (ATCM) and, as such, performs its duties under the ATCM's direction. The ATCM is the forum that brings together the Antarctic Treaty Consultative Parties, Non-Consultative Parties, Observers and Experts. The Antarctic Treaty was signed in 1959 and entered into force in 1961. The Secretariat is located at 757 Maipú Street, in the Autonomous City of Buenos Aires, Argentina. The Government of Argentina provides the office where the Secretariat operates, and the Headquarters Agreement –signed in 2010, during ATCM XXXIII—establishes the relationship between the ATCM and the Argentine Republic regarding the operations of the Secretariat in Argentina. Mission The mission of the Secretariat is to assist the ATCM and the Committee for Environmental Protection (CEP) in performing their functions, with the aim of strengthening the Antarctic Treaty System and ensuring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antarctic Specially Managed Area
An Antarctic Specially Managed Area (ASMA) is a protected area on the continent of Antarctica, or on its adjacent islands. ASMAs are managed by the governments of Brazil, Poland, Ecuador, Peru, United States, New Zealand, Australia, Norway, Spain, United Kingdom, Chile, India, Russia, and Romania. The purpose of the ASMA sites are "to assist in the planning and coordination of activities within a specified area, avoid possible conflicts, improve cooperation between ATCPs and minimise environmental impacts. ASMAs may include areas where activities pose risks of mutual interference or cumulative environmental impacts, as well as sites or monuments of recognised historical value." Unlike the Antarctic Specially Protected Areas An Antarctic Specially Protected Area (ASPA) is an area on the continent of Antarctica, or on nearby islands, which is protected by scientists and several different international bodies. The protected areas were established in 1961 under the Antarct ..., ASMAs do n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taylor Glacier
__NOTOC__ The Taylor Glacier is an Antarctic glacier about long, flowing from the plateau of Victoria Land into the western end of Taylor Valley, north of the Kukri Hills, south of the Asgard Range. The middle part of the glacier is bounded on the north by the Inland Forts and on the south by Beacon Valley. History The glacier was discovered by the British National Antarctic Expedition (1901–04) and at that time thought to be a part of Ferrar Glacier. The Western Journey Party of the British Antarctic Expedition of 1910 determined that the upper and lower portions of what was then known as Ferrar Glacier are apposed, i.e., joined in Siamese-twin fashion north of Knobhead. With this discovery Robert Falcon Scott named the upper portion for Thomas Griffith Taylor, geologist and leader of the Western Journey Party. Glaciology Research The Taylor Glacier has been the focus of a measurement and modeling effort carried out by researchers from the University of California, B ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anaerobic Bacteria
An anaerobic organism or anaerobe is any organism that does not require molecular oxygen for growth. It may react negatively or even die if free oxygen is present. In contrast, an aerobic organism (aerobe) is an organism that requires an oxygenated environment. Anaerobes may be unicellular (e.g. protozoans, bacteria) or multicellular. Most fungi are obligate aerobes, requiring oxygen to survive. However, some species, such as the Chytridiomycota that reside in the rumen of cattle, are obligate anaerobes; for these species, anaerobic respiration is used because oxygen will disrupt their metabolism or kill them. Deep waters of the ocean are a common anoxic environment. First observation In his letter of 14 June 1680 to The Royal Society, Antonie van Leeuwenhoek described an experiment he carried out by filling two identical glass tubes about halfway with crushed pepper powder, to which some clean rain water was added. Van Leeuwenhoek sealed one of the glass tubes using a flame and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
