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The European Project for Ice Coring in Antarctica (EPICA) is a multinational European project for deep ice core drilling in Antarctica. Its main objective is to obtain full documentation of the climatic and atmospheric record archived in Antarctic ice by drilling and analyzing two ice cores and comparing these with their Greenland counterparts (GRIP and GISP). Evaluation of these records will provide information about the natural climate variability and mechanisms of rapid climatic changes during the last glacial epoch.
The European Science Foundation EPICA Programme (1996–2005) provides co-ordination for EPICA drilling activities at Dome Concordia and Kohnen Station, which are supported by the European Commission and by national contributions from Belgium, Denmark, France, Germany, Italy, the Netherlands, Norway, Sweden, Switzerland and the United Kingdom.
Deep drilling took place at two sites in Antarctica: Concordia Station at Dome C and Kohnen Station.
In 2008 the project received the Descartes Prize for Research. [1]
This site ( 75°06′S123°21′E / 75.100°S 123.350°E , 3233 m above sea level, 560 km from Vostok Station) was chosen to obtain the longest undisturbed chronicle of environmental change, in order to characterise climate variability over several glacial cycles, and to study potential climate forcings and their relationship to events in other regions. The core goes back 740,000 years and reveals 8 previous glacial cycles. Drilling was completed at this site in December 2004, reaching a drilling depth of 3270.2 m, 5 m above bedrock. Present-day annual average air temperature is −54.5 °C and snow accumulation 25 mm/y. Information about the core was first published in Nature on 10 June 2004. [2]
The picture shows delta deuterium data (a proxy for temperature: more negative values indicate lower temperatures) from both EPICA and Vostok. The upper plot, with x-axis being age (years before 1950) clearly shows the extra information in the EPICA core before the start of the Vostok record. The lower picture, plotted against depth, shows how compressed the deeper parts of the cores are: the earliest 100 kyr (thousand years) of the EPICA core are in the bottom 100 m of the core.
Before 400 kyr the character of the ice ages are seen to be somewhat different: interglacial warmth is distinctly less warm than the four most recent interglacials; however, the interglacial periods before 400 kyr occupied a much larger proportion of each cycle than subsequently. The interglacial 400 kyr ago, which is believed (from arguments about the configuration of the orbital parameters of the earth) to be an approximate analogue to the current interglacial, was quite long: 28 kyr. The Nature paper argues that if this analogue is accepted, then the current climate would be expected to continue like today's, in the absence of human influence (which it states is unlikely, given the predicted increases in greenhouse gas concentrations).
Further analysis of the core is hoped to extend the record back somewhat further, possibly as far as the Brunhes–Matuyama magnetic reversal, believed to be at about 780 kyr.
The core time scale is derived from the measured depth scale by a model incorporating surface snow accumulation variations, ice thinning, basal heat fluxes, etc., and is empirically "tied" at 4 times by matches to the marine isotopic record.
Kohnen Station is located at 75°00′S00°04′E / 75.000°S 0.067°E , 2892 m above sea level. Higher annual snowfall and sensitivity to conditions over the South Atlantic will allow the study of any links between shifts in the Atlantic Ocean circulation and the rapid climate events detected over Greenland.
The European project "Beyond EPICA – Oldest Ice" [3] aims at obtaining older ice cores, which are expected to provide climatic data up to 1.5 million years old. A drill site, "Little Dome C", was chosen in 2022 and drilling operations will take place in the following years. [4]
An ice age is a long period of reduction in the temperature of Earth's surface and atmosphere, resulting in the presence or expansion of continental and polar ice sheets and alpine glaciers. Earth's climate alternates between ice ages and greenhouse periods, during which there are no glaciers on the planet. Earth is currently in the ice age called Quaternary glaciation. Individual pulses of cold climate within an ice age are termed glacial periods, and intermittent warm periods within an ice age are called interglacials or interstadials.
Lake Vostok is the largest of Antarctica's 675 known subglacial lakes. Lake Vostok is located at the southern Pole of Cold, beneath Russia's Vostok Station under the surface of the central East Antarctic Ice Sheet, which is at 3,488 m (11,444 ft) above mean sea level. The surface of this fresh water lake is approximately 4,000 m (13,100 ft) under the surface of the ice, which places it at approximately 500 m (1,600 ft) below sea level.
Vostok Station is a Russian research station in inland Princess Elizabeth Land, Antarctica. Founded by the Soviet Union in 1957, the station lies at the southern Pole of Cold, with the lowest reliably measured natural temperature on Earth of −89.2 °C. Research includes ice core drilling and magnetometry. Vostok was named after Vostok, the lead ship of the First Russian Antarctic Expedition captained by Fabian von Bellingshausen. The Bellingshausen Station was named after this captain.
An ice core is a core sample that is typically removed from an ice sheet or a high mountain glacier. Since the ice forms from the incremental buildup of annual layers of snow, lower layers are older than upper ones, and an ice core contains ice formed over a range of years. Cores are drilled with hand augers or powered drills; they can reach depths of over two miles (3.2 km), and contain ice up to 800,000 years old.
Dansgaard–Oeschger events, named after palaeoclimatologists Willi Dansgaard and Hans Oeschger, are rapid climate fluctuations that occurred 25 times during the last glacial period. Some scientists say that the events occur quasi-periodically with a recurrence time being a multiple of 1,470 years, but this is debated. The comparable climate cyclicity during the Holocene is referred to as Bond events.
Dome C, also known as Dome Circe, Dome Charlie or Dome Concordia, located at Antarctica at an elevation of 3,233 metres (10,607 ft) above sea level, is one of several summits or "domes" of the Antarctic Ice Sheet. Dome C is located on the Antarctic Plateau, 1,100 kilometres (680 mi) inland from the French research station at Dumont D'Urville, 1,100 kilometres (680 mi) inland from the Australian Casey Station and 1,200 kilometres (750 mi) inland from the Italian Zucchelli station at Terra Nova Bay. Russia's Vostok Station is 560 kilometres (350 mi) away. Dome C is the site of the Concordia Research Station, jointly operated by France and Italy.
Concordia Research Station, which opened in 2005, is a French–Italian research facility that was built 3,233 m (10,607 ft) above sea level at a location called Dome C on the Antarctic Plateau, Antarctica. It is located 1,100 km (680 mi) inland from the French research station at Dumont D'Urville, 1,100 km (680 mi) inland from Australia's Casey Station and 1,200 km (750 mi) inland from the Italian Zucchelli Station at Terra Nova Bay. Russia's Vostok Station is 560 km (350 mi) away. The Geographic South Pole is 1,670 km (1,040 mi) away. The facility is also located within Australia's claim on Antarctica, the Australian Antarctic Territory.
The global temperature record shows the fluctuations of the temperature of the atmosphere and the oceans through various spans of time. There are numerous estimates of temperatures since the end of the Pleistocene glaciation, particularly during the current Holocene epoch. Some temperature information is available through geologic evidence, going back millions of years. More recently, information from ice cores covers the period from 800,000 years before the present time until now. A study of the paleoclimate covers the time period from 12,000 years ago to the present. Tree rings and measurements from ice cores can give evidence about the global temperature from 1,000-2,000 years before the present until now. The most detailed information exists since 1850, when methodical thermometer-based records began. Modifications on the Stevenson-type screen were made for uniform instrument measurements around 1880.
The Greenland Ice Core Project (GRIP) was a research project organized through the European Science Foundation (ESF). The project ran from 1989 to 1995, with drilling seasons from 1990 to 1992. In 1988, the project was accepted as an ESF-associated program, and the fieldwork was started in Greenland in the summer of 1989.
The Mirny Station is a Russian first Antarctic science station located in Queen Mary Land, Antarctica, on the Antarctic coast of the Davis Sea.
Dome Fuji, also called Dome F or Valkyrie Dome, is an Antarctic base located in the eastern part of Queen Maud Land at 77°30′S37°30′E. With an altitude of 3,810 metres (12,500 ft) above sea level, it is the second-highest summit or ice dome of the East Antarctic Ice Sheet and represents an ice divide. Dome F is the site of Dome Fuji Station, a research station operated by Japan.
Jean-Robert Petit studied chemistry and physics at the University of Grenoble and received a PhD in 1984 in paleoclimatology on the study of the aeolian dust record from Antarctic ice cores.
The 100,000-year problem of the Milankovitch theory of orbital forcing refers to a discrepancy between the reconstructed geologic temperature record and the reconstructed amount of incoming solar radiation, or insolation over the past 800,000 years. Due to variations in the Earth's orbit, the amount of insolation varies with periods of around 21,000, 40,000, 100,000, and 400,000 years. Variations in the amount of incident solar energy drive changes in the climate of the Earth, and are recognised as a key factor in the timing of initiation and termination of glaciations.
Dye 3 is an ice core site and previously part of the DYE section of the Distant Early Warning (DEW) line, located at in Greenland. As a DEW line base, it was disbanded in years 1990/1991.
Kohnen-Station is a German summer-only polar research station in the Antarctic, able to accommodate up to 28 people. It is named after the geophysicist Heinz Kohnen (1938–1997), who was for a long time the head of logistics at the Alfred Wegener Institute.
There are hundreds of antarctic lakes in Antarctica. In 2018 researchers at the Alfred Wegener Institute for Polar and Marine Research published a study they claimed cast doubt on the earlier estimate that there were almost 400 subglacial antarctic lakes. Antarctica also has some relatively small regions that are clear of ice and snow, and there are some surface lakes in these regions. They called for on the ground seismic studies, or drilling, to determine a more reliable number.
The Mid-Brunhes Event (MBE) is a climatic shift evident in a number of marine sediment and Antarctic ice cores. It corresponds to an increase in amplitude of glacial-interglacial cycles.
Research stations in Queen Maud Land are connected by the Dronning Maud Land Air Network Project (DROMLAN), which is a cooperative agreement for transportation between eleven nations with research stations in East Antarctica. Long-range aircraft fly between Cape Town, South Africa and either the Troll Airfield, located at the Troll research station, or the runway at the Novolazarevskaya Station. From these two main airfields, smaller aircraft may fly further to other Antarctic destinations.
Dorthe Dahl-Jensen is a Danish palaeoclimatology professor and researcher at the Centre for Ice and Climate at the Niels Bohr Institute, University of Copenhagen in Denmark. Her primary field is the study of ice and climate, specifically the reconstruction of climate records from ice cores and borehole data; ice flow models to date ice cores; continuum mechanical properties of anisotropic ice; ice in the solar system; and the history and evolution of the Greenland Ice Sheet.
Jérôme Chappellaz is a French glaciologist, geochemist and paleoclimatologist who is director of the French Polar Institute. A senior researcher at France's National Center for Scientific Research (CNRS), he is a co-founder and chairman of the Ice Memory Foundation.