Last Glacial Maximum
The Last Glacial Maximum was the most recent time during the Last Glacial Period when ice sheets were at their greatest extent. Vast ice sheets covered much of North America, northern Europe, Asia; the ice sheets profoundly affected Earth's climate by causing drought, a large drop in sea levels. The ice sheets reached their maximum coverage about 26,500 years ago. Deglaciation commenced in the Northern Hemisphere at 20 ka and in Antarctica at 14.5 ka, consistent with evidence for an abrupt rise in the sea level at about 14.5 ka. The LGM is referred to in Britain as the Dimlington Stadial, dated by Nick Ashton to between 31 and 16 ka. In the archaeology of Paleolithic Europe, the LGM spans the Gravettian, Magdalenian and Périgordian; the LGM was followed by the Late Glacial. According to Blue Marble 3000, the average global temperature around 19,000 BC was 9.0 °C. This is about 6.0 °C colder than the 2013-2017 average. The figures given by the Intergovernmental Panel On Climate Change estimate a lower global temperature than the figures given by the Zurich University of Applied Sciences.
However, these figures are open more to interpretation. According to the IPCC, average global temperatures increased by 5.5 ± 1.5 °C since the last glacial maximum, the rate of warming was about 10 times slower than that of the 20th Century. It appears that they are defining the present as sometime in the 19th Century for this case, but they don’t specify exact years, or give a temperature for the present. Berkeley Earth puts out a list of average global temperatures by year. If you average all of the years from 1850 to 1899, the average temperature comes out to 13.8 °C. When subtracting 5.5 ± 1.5 °C from the 1850-1899 average, the average temperature for the last glacial maximum comes out to 8.3 ± 1.5 °C. This is about 6.7 ± 1.5 °C colder than the 2013-2017 average. This figure is open to interpretation because the IPCC does not specify 1850-1899 as being the present, or give any exact set of years as being the present, it does not state whether or not they agree with the figures given by Berkeley Earth.
According to the United States Geological Survey, permanent summer ice covered about 8% of Earth's surface and 25% of the land area during the last glacial maximum. The USGS states that sea level was about 125 meters lower than in present times; when comparing to the present, the average global temperature was 15.0 °C for the 2013-2017 period. About 3.1% of Earth's surface and 10.7% of the land area is covered in year-round ice. The formation of an ice sheet or ice cap requires both prolonged precipitation. Hence, despite having temperatures similar to those of glaciated areas in North America and Europe, East Asia remained unglaciated except at higher elevations; this difference was. These anticyclones generated air masses that were so dry on reaching Siberia and Manchuria that precipitation sufficient for the formation of glaciers could never occur; the relative warmth of the Pacific Ocean due to the shutting down of the Oyashio Current and the presence of large'east-west' mountain ranges were secondary factors preventing continental glaciation in Asia.
All over the world, climates at the Last Glacial Maximum were cooler and everywhere drier. In extreme cases, such as South Australia and the Sahel, rainfall could be diminished by up to 90% from present, with florae diminished to the same degree as in glaciated areas of Europe and North America. In less affected regions, rainforest cover was diminished in West Africa where a few refugia were surrounded by tropical grasslands; the Amazon rainforest was split into two large blocks by extensive savanna, the tropical rainforests of Southeast Asia were affected, with deciduous forests expanding in their place except on the east and west extremities of the Sundaland shelf. Only in Central America and the Chocó region of Colombia did tropical rainforests remain intact – due to the extraordinarily heavy rainfall of these regions. Most of the world's deserts expanded. Exceptions were in what is now the western United States, where changes in the jet stream brought heavy rain to areas that are now desert and large pluvial lakes formed, the best known being Lake Bonneville in Utah.
This occurred in Afghanistan and Iran, where a major lake formed in the Dasht-e Kavir. In Australia, shifting sand dunes covered half the continent, whilst the Chaco and Pampas in South America became dry. Present-day subtropical regions lost most of their forest cover, notably in eastern Australia, the Atlantic Forest of Brazil, southern China, where open woodland became dominant due to drier conditions. In northern China – unglaciated despite its cold climate – a mixture of grassland and tundra prevailed, here, the northern limit of tree growth was at least 20° farther south than today. In the period before the Last Glacial Maximum, many areas that became barren desert were wetter than they are today, notably in southern Australia, where Aboriginal occupation is believed to coincide with a wet period between 40,000 and 60,000 years Before Present. During the Last Glacial Maximum, much of the world was cold and inhospitable
A glacial period is an interval of time within an ice age, marked by colder temperatures and glacier advances. Interglacials, on the other hand, are periods of warmer climate between glacial periods; the last glacial period ended about 15,000 years ago. The Holocene epoch is the current interglacial. A time with no glaciers on Earth is considered a greenhouse climate state. Within the Quaternary, there have been a number of interglacials; the last glacial period was the most recent glacial period within the Quaternary Ice Age, occurring in the Pleistocene epoch, which began about 110,000 years ago and ended about 15,000 years ago. The glaciations that occurred during this glacial period covered many areas of the Northern Hemisphere and have different names, depending on their geographic distributions: Wisconsin, Midlandian, Würm, Dali, Taibai Luojishan, Tianchi Qomolangma, Llanquihue; the glacial advance reached its maximum extent about 18,000 BP. In Europe, the ice sheet reached Northern Germany.
In the last 650,000 years, there were, on average, seven cycles of glacial retreat. Since orbital variations are predictable, computer models that relate orbital variations to climate can predict future climate possibilities. Work by Berger and Loutre suggests; the amount of heat trapping gases emitted into Earth's Oceans and atmosphere will prevent the next glacial period, which otherwise would begin in around 1,000 years, more glacial cycles
Verkhoyansk is a town in Verkhoyansky District of the Sakha Republic, located on the Yana River near the Arctic Circle, 92 kilometers from Batagay, the administrative center of the district, 675 kilometers north of Yakutsk, the capital of the republic. As of the 2010 Census, its population was 1,311; the town holds the Guinness world record for the greatest temperature range on Earth: 105 °C. Cossacks founded an ostrog in 90 kilometers southwest of the modern town; the ostrog's name "Verkhoyansky" translating from Russian as the town on the Upper Yana, derived from its geographical location on the upper reaches of the Yana River. In 1775, it was moved to the left bank of the Yana River to facilitate tax collection, it was granted town status in 1817. Between the 1860s and 1917, the town was a place of political exile, with some of the more prominent exiles including the Polish writer Wacław Sieroszewski, as well as Bolshevik revolutionaries Ivan Babushkin and Viktor Nogin; as an inhabited locality, Verkhoyansk is classified as a town under district jurisdiction.
Within the framework of administrative divisions, it is incorporated within Verkhoyansky District as the Town of Verkhoyansk. As a municipal division, the Town of Verkhoyansk is incorporated within Verkhoyansky Municipal District as Verkhoyansk Urban Settlement. There is a river port, an airport, a fur-collecting depot, the center of a reindeer-raising area, it is home to the Pole of Cold Museum. Verkhoyansk is notable chiefly for its exceptionally low winter temperatures and some of the greatest temperature differences on Earth between summer and winter. Average monthly temperatures range from −45.4 °C in January to +16.5 °C in July. Mean monthly temperatures are below freezing from October through April and exceed +10 °C from June through August, with the intervening months of May and September constituting short transitional seasons. Verkhoyansk has an extreme subarctic climate dominated much of the year by high pressure; this has the effect of cutting off the region from warming influences in winter and together with a lack of cloud cover leads to extensive heat losses during the cooler months.
Verkhoyansk is one of the places considered the northern Pole of Cold, the others being Oymyakon, located 629 km away by air, Delyankir. The lowest temperature recorded there, in February 1892, was −67.6 °C, recorded on February 5 and 7. This was the coldest recorded temperature in the Northern Hemisphere. However, on February 6, 1933, the temperature at Oymyakon reached −67.7 °C, just exceeding Verkhoyansk's record. Only Antarctica has recorded lower temperatures than Oymyakon or Verkhoyansk: the lowest directly recorded temperature at ground level is −89.2 °C, recorded at the Vostok Station in Antarctica on July 21, 1983. and a temperature of −93.2 °C was recorded via satellite observations at the East Antarctic Plateau in Antarctica on August 10, 2010. In this area, temperature inversions form in winter due to the cold and dense air of the Siberian High pooling in deep hollows, so that temperatures increase rather than decrease with higher altitude. In Verkhoyansk it sometimes happens that the average minimum temperatures for January and December are below −50 °C.
Oymyakon and Verkhoyansk are the only two permanently populated places in the world that have recorded temperatures below −60.0 °C every day of January. In June and August, daytime temperatures over +30 °C are not uncommon; the warmest month on record is July 2001, at +21.9 °C. The average annual temperature for Verkhoyansk is −14.5 °C. On July 25, 1988, Verkhoyansk recorded a temperature of +37.3 °C, yielding a temperature range of 105 °C based on reliable records, the greatest temperature range in the world. Oymyakon and Yakutsk are the only other places in the world with a temperature range higher than 100 °C. Verkhoyansk has never recorded a temperature above freezing between November 10 and March 14. Verkhoyansk has a dry climate with little rainfall or snowfall: the average annual precipitation is 180 millimeters. Although no month can be described as wet, there are strong seasonal differences in precipitation, with the summer being much wetter than the winter. Winter precipitation is light because of the dominance of high pressure at this time of year.
Official website of the Sakha Republic. Registry of the Administrative-Territorial Divisions of the Sakha Republic. Verkhoyansky District. Государственное Собрание Республики Саха. Закон №173-З №353-III от 30 ноября 2004 г. «Об установлении границ и о наделении статусом городского и сельского поселений муниципальных образований Республики Саха », в ред. Закона №1058-З №1007-IV от 25 апреля 2012 г. «О внесении изменений в Закон Республики Саха "Об установлении границ и о наделении статусом городского и сельского поселений муниципальных образований Республики Саха"». Вступил в силу со дня официального опубликования. Опубликован: "Якутия", №245, 31 декабря 2004 г. (State Assembly of the Sakha Republic. Law #173-Z No. 353-III of November 30, 2004 On Establishing the Borders and on Granting the Urban and Rural Settlement Status to the Municipal Formations of the Sakha Republic, as amended by the Law #1058-Z No. 1007-IV of April 25, 2012 On Amending the Law of the Sakha Republic "On Establishing the Borders and on Granting the Urban and Rural Settlement Status to the Municipal Form
The Indigirka River is a river in the Sakha Republic in Russia between the Yana River and the Kolyma River. It is 1,726 kilometres long; the area of its basin is 360,000 square kilometres. The river flows into East Siberian Sea, it stays under the ice until May -- June. The main tributaries are the: Kuydusun River Kyuente River Elgi River Nera River, Moma River Badyarikha River Selennyakh River Uyandina Main ports on the river are: Khonuu Druzhina Chokurdakh Tabor. There is a gold prospecting industry in the Indigirka basin. Ust-Nera, a gold-mining center, is the largest settlement on the river; the Indigirka River teems with a variety of fishes. Among the most valuable are several whitefish species, such as vendace, muksun, omul, etc; the isolated village of Russkoye Ustye, located on the delta of the Indigirka, is known for the unique traditional culture of the Russian settlers whose ancestors came there several centuries ago. Some historians have speculated. In 1638 Ivan Rebrov reached the Indigirka.
In 1636–42 Elisei Buza pioneered the overland route to the Indigirka river system. At about the same time, Poznik Ivanov ascended a tributary of the lower Lena, crossed the Verkhoyansk Range to the upper Yana and crossed the Chersky Range to the Indigirka. In 1642 Mikhail Stadukhin reached the Indigirka overland from the Lena. Zashiversk on the Indigirka was an important colonial outpost during the early days of Russian colonization, it was subsequently abandoned in the 19th century. Other historical settlements, now long abandoned, were Uyandinskoye Zimov ` ye. In 1892–94 Baron Eduard Von Toll carried out geological surveys in the basin of the Indigirka on behalf of the Russian Academy of Sciences. During one year and two days the expedition covered 25,000 kilometres, of which 4,200 kilometres were up rivers, carrying out geodesic surveys en route; the Indigirka forms a large delta, consisting of a number of islands. About 100 kilometres before reaching the East Siberian Sea, the river splits into two major northeast-flowing streams.
The left arm is known as the Russko-Ustyinskaya Protoka. Further downstream, the third major arm, the Kolymskaya Protoka splits off the Srednyaya Protoka as its right distributary, thus justifying the "middle" moniker for the Srednyaya Protoka. While Srednyaya Protoka means the "Middle Arm", the names of the main western and eastern arms indicate their relative location as well; the Kolymskaya Protoka, or Kolymskoye Ustye is the arm one located on the eastern side, i.e. the "Kolyma side" of the delta. The Russko-Ustyinskaya Protoka known earlier as Russkoye Ustye is the arm one located on the western side, i.e. the "Russian side" of the delta. These days the name of the Russko-Ustyinskaya Protoka appears as if it were formed from the name of the old Russian village Russkoye Ustye situated there, but the opposite is to have been the case, the village being named after the river arm on which it was located. Several flat islands are formed by the channels of the delta. Listed from the east to the west, the major ones are: Usun-Ary 71.387°N 151.255°E / 71.387.
It is 12 kilometres and 2.7 kilometres wide. Uparovskiy Island 71.582°N 151.196°E / 71.582. It is 1 km wide. Ploskiy Island 71.480°N 150.890°E / 71.480. It is about 3 km long. Bolshoy Fedorovskiy 71.533°N 150.510°E / 71.533. It has a maximum width of 4 km. Vkodnoy and Oleniy islands lie right at the Prot. Russko Ust'inskaya mouth 71.546°N 150.266°E / 71.546. Both are of about 4 km in length. Krestovyy Island 71.447°N 149.766°E / 71.447. It is 1.6 km wide. Indigirka at GEOnet Names Server Location of islands William Barr, Baron Eduard Von Toll's Last Expedition. Arctic, Sept 1980
Ust-Kuyga is an urban locality in Ust-Yansky District of the Sakha Republic, located 224 kilometers from Deputatsky, the administrative center of the district, on the Yana River. As of the 2010 Census, its population was 979. Urban-type settlement status was granted to Ust-Kuyga in 1967. Within the framework of administrative divisions, the urban-type settlement of Ust-Kuyga is incorporated within Ust-Yansky District as the Settlement of Ust-Kuyga; as a municipal division, the Settlement of Ust-Kuyga is incorporated within Ust-Yansky Municipal District as Ust-Kuyga Urban Settlement. Ust-Kuyga is served by the Ust-Kuyga Airport. Official website of the Sakha Republic. Registry of the Administrative-Territorial Divisions of the Sakha Republic. Ust-Yansky District. Государственное Собрание Республики Саха. Закон №173-З №353-III от 30 ноября 2004 г. «Об установлении границ и о наделении статусом городского и сельского поселений муниципальных образований Республики Саха », в ред. Закона №1058-З №1007-IV от 25 апреля 2012 г.
«О внесении изменений в Закон Республики Саха "Об установлении границ и о наделении статусом городского и сельского поселений муниципальных образований Республики Саха"». Вступил в силу со дня официального опубликования. Опубликован: "Якутия", №245, 31 декабря 2004 г
Pole of Cold
The Poles of Cold are the places in the southern and northern hemispheres where the lowest air temperatures have been recorded. In the southern hemisphere, the Pole of Cold is located in Antarctica, at the Russian Antarctic station Vostok at 78°28′S 106°48′E. On July 21, 1983, this station recorded a temperature of −89.2 °C. This is the lowest occurring temperature recorded on Earth. Vostok station is located at the elevation of 3,488 m above sea level, far removed from the moderating influence of oceans, high latitude that results in three months of civil polar night every year, all combine to produce an environment where temperatures rise above −25 °C during summer and fall below −70 °C in winter. By comparison, the South Pole, due to its lower elevation, is, on average, 5 to 10 °C warmer than Vostok, the lowest temperature recorded at the South Pole is −82.8 °C. It is thought that Vostok is not the coldest place in Antarctica, there are locations that are modestly colder on average; the now inactive Plateau Station, located on the central Antarctic plateau, recorded an average yearly temperature, lower than that of Vostok Station during the 37-month period that it was active in the late 1960s, with its average for the coldest month being several degrees lower than the same statistic for Vostok.
Plateau Station never recorded a temperature. However, temperatures at Plateau Station were only recorded during the 37 months. Had a lower temperature than the Vostok record occurred there at a date, it would never have been recorded. Monitoring stations in Antarctica are few and far between. Temperatures below −89.2 °C, if they did occur elsewhere, would not have been recorded. The automatic weather station at Dome A was only installed in 2005, has recorded −82.5 °C as the coldest so far. However a review of satellite measurements taken between 2010–2013 found several places located along a ridge between Dome A and Dome F which recorded lower temperatures of −92 to −94 °C, with the lowest reliable temperature being −93.2 °C recorded in 2010, at 81°48′S 59°18′E, at an elevation of 3,900 m. The extreme low temperatures are found in hollows below the peak of the ice ridge, where cold air gets trapped as it flows downhill, since the same low temperature ranges were detected at several different sites along the ridge across multiple years, it is thought this may be the lowest temperature achievable under local atmospheric conditions.
In the northern hemisphere, there are two places in the Sakha Republic, Russia that vie for the honour of being considered the "Pole of Cold" in winter. These are Oymyakon. In December 1868 and in February 1869 Ivan Khudyakov made the discovery of the Northern Pole of Cold by measuring a record temperature of −63.2 °C in Verkhoyansk. On January 15, 1885, a temperature of −67.8 °C was registered there by Sergey Kovalik. This measurement was published in the Annals of the General Physical Observatory in 1892. One can still find this incorrect value in some literature; the coldest reliably measured temperature in Verkhoyansk was −67.6 °C on February 5 and 7 of 1892. On February 6, 1933, a temperature of −67.7 °C was recorded at Oymyakon's weather station. This is the coldest reliably measured temperature for the Northern Hemisphere; the weather station is in a valley between Tomtor. The station is at 750 m and the surrounding mountains at 1,100 m, causing cold air to pool in the valley: recent studies show that winter temperatures in the area increase with elevation by as much as 10 °C.
The small rural locality of Delyankir in the Sakha Republic, has a lower average temperature throughout all winter months than either Oymyakon or Verkhoyansk, as well as a lower yearly average. Its record low temperature of −65 °C is higher than the record lows set at Oymyakon and Verkhoyansk, however. List of weather records Life in the Freezer Living in Antarctica Ask about life in the Pole of Cold Visit the Pole of Cold
In geology, permafrost is ground, including rock or soil, at or below the freezing point of water 0 °C for two or more years. Most permafrost is located in high latitudes, but at lower latitudes alpine permafrost occurs at higher elevations. Ground ice is not always present, as may be in the case of non-porous bedrock, but it occurs and it may be in amounts exceeding the potential hydraulic saturation of the ground material. Permafrost accounts for 0.022% of total water on Earth and the permafrost region covers 24% of exposed land in the Northern Hemisphere. It occurs subsea on the continental shelves of the continents surrounding the Arctic Ocean, portions of which were exposed during the last glacial period; the thawing of permafrost has implications for the global climate. A global temperature rise of 1.5 °C above current levels would be enough to start the thawing of permafrost in Siberia, according to one group of scientists. "In contrast to the relative dearth of reports on frozen ground in north America prior to World War II, a vast literature on the engineering aspects of permafrost was available in Russian.
Beginning in 1942, Siemon William Muller delved into the relevant Russian literature held by the Library of Congress and the U. S. Geological Survey Library so that he was able to furnish the government an engineering field guide and a technical report about permafrost by 1943", year in which he coined the term as a contraction of permamently frozen ground. Although classified, in 1947 a revised report was released publicly, regarded as the first North American treatise on the subject. Permafrost is soil, rock or sediment, frozen for more than two consecutive years. In areas not overlain by ice, it exists beneath a layer of soil, rock or sediment, which freezes and thaws annually and is called the "active layer". In practice, this means that permafrost occurs at an mean annual temperature of − 2 colder. Active layer thickness is 0.3 to 4 meters thick. The extent of permafrost varies with the climate: in the Northern Hemisphere today, 24% of the ice-free land area, equivalent to 19 million square kilometers, is more or less influenced by permafrost.
Of this area more than half is underlain by continuous permafrost, around 20 percent by discontinuous permafrost, a little less than 30 percent by sporadic permafrost. Most of this area is found in Siberia, northern Canada and Greenland. Beneath the active layer annual temperature swings of permafrost become smaller with depth; the deepest depth of permafrost occurs. Above that bottom limit there may be permafrost, whose temperature doesn't change annually—"isothermal permafrost". Permafrost forms in any climate where the mean annual air temperature is less than the freezing point of water. Exceptions are found in moist-wintered forest climates, such as in Northern Scandinavia and the North-Eastern part of European Russia west of the Urals, where snow acts as an insulating blanket. Glaciated areas may be exceptions. Since all glaciers are warmed at their base by geothermal heat, temperate glaciers, which are near the pressure-melting point throughout, may have liquid water at the interface with the ground and are therefore free of underlying permafrost.
"Fossil" cold anomalies in the Geothermal gradient in areas where deep permafrost developed during the Pleistocene persist down to several hundred metres. This is evident from temperature measurements in boreholes in North Europe; the below-ground temperature varies less from season to season than the air temperature, with mean annual temperatures tending to increase with depth as a result of the geothermal crustal gradient. Thus, if the mean annual air temperature is only below 0 °C, permafrost will form only in spots that are sheltered—usually with a northerly aspect—creating discontinuous permafrost. Permafrost will remain discontinuous in a climate where the mean annual soil surface temperature is between −5 and 0 °C. In the moist-wintered areas mentioned before, there may not be discontinuous permafrost down to −2 °C. Discontinuous permafrost is further divided into extensive discontinuous permafrost, where permafrost covers between 50 and 90 percent of the landscape and is found in areas with mean annual temperatures between −2 and −4 °C, sporadic permafrost, where permafrost cover is less than 50 percent of the landscape and occurs at mean annual temperatures between 0 and −2 °C.
In soil science, the sporadic permafrost zone is abbreviated SPZ and the extensive discontinuous permafrost zone DPZ. Exceptions occur in un-glaciated Siberia and Alaska where the present depth of permafrost is a relic of climatic conditions during glacial ages where winters were up to 11 °C colder than those of today. At mean annual soil surface temperatures below −5 °C the influence of aspect can never be sufficient to thaw permafrost and a zone of continuous permafrost forms. A line of continuous permafrost in the Northern Hemisphere represents the most southerly border where land is covered by continuous permafrost or glacial ice; the line of continuous permafrost varies around the world northward or southward due to regional climatic changes. In the southern hemisphere, most of the equivalent line would fall within the Southern Ocean if there were land there. Most of the Antarctic continent is overl