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87-696: The gradual warming since the Last Glacial Maximum (27,000 to 24,000 years BP) has been interrupted by two cold spells: the Older Dryas and the Younger Dryas (c. 12,900–11,650 BP). In northern Scotland , the glaciers were thicker and deeper during the Older Dryas than the succeeding Younger Dryas, and there is no evidence of human occupation of Britain . In Northwestern Europe there was also an earlier Oldest Dryas (18.5–17 ka BP 15–14 ka BP). The Dryas are named after an indicator genus,

174-410: A change to colder climate. Microstructure observation of the sediments shows that fossil soil wedges or frost cracks were observed in the top of Older Dryas deposits, which indicates mean annual air temperatures below −1 to 0 °C and cold winters. This conclusion is also supported by the presence of Juniperus , which indicates a protecting snow cover in winter. This change is also shown on the records at

261-473: A cold oscillation between 14,025 to13,904 years BP, which is reflected in the increased δO during this period. This cold oscillation was also observed in earlier ice core records (GRIP and GISP2) drilled in the early 1990s by GRIP members. A multi-proxy study on late glacial lake sediments of Moervaart palaeolake shows multiple pieces of evidence in various aspects to support Older Dryas. The lake sediment had an erosional surface prior to Older Dryas suggesting

348-402: A cold oscillation in the second late-glacial (LG2) following the first late-glacial readvance (LG1) at around 14,000±700 to 13,700±1200 years BP. The LG2 cold oscillation around 14,000 years BP can correspond to the cooling of Greenland Interstadial 1 (GI-1d-Older Dryas) that happened around the same time period, which is the first chronological evidence that supports the presence of Older Dryas in

435-520: A cold reversal caused a replacement of much of the arboreal vegetation with Magellanic moorland and Alpine species. On Isla Grande de Chiloé , Magellanic moorland and closed-canopy Nothofagus forests were both present during the LGM, but the former disappeared by the late LGM. Little is known about the extent of glaciers during Last Glacial Maximum north of the Chilean Lake District . To

522-465: A cold-water indicator) suggests a lower summer temperature compared to previous Bølling period. Recent research on sea surface temperature (SST) for the past 15,000 years in southern Okinawa modelled the Paleoclimate of ocean sediment core (ODP 1202B) using an alkenone analysis. The results show a cooling stage at 14,300 to 13,700 years BP between Bølling and Allerød warm phases, corresponding to

609-730: A formal measurement of uncalibrated radiocarbon years , counted from 1950). In New Zealand and neighbouring regions of the Pacific, temperatures may have been further depressed during part of the LGM by the world's most recent supervolcanic eruption , the Oruanui eruption , approximately 25,500 years BP. However, it is estimated that during the LGM, low-to-mid latitude land surfaces at low elevation cooled on average by 5.8 °C relative to their present-day temperatures, based on an analysis of noble gases dissolved in groundwater rather than examinations of species abundances that have been used in

696-598: A heavy breed, similar to a Great Dane , perhaps useful to run down Elephantidae . The large number of mammoth bones at campsites make it clear that even then, the Elephantidae in Europe were approaching the limit of their duration. Their bones were used for many purposes, one being the numerous objects of art, including an engraved star map. Late Upper Palaeolithic culture was by no means uniform. Many local traditions have been defined. The Hamburgian culture had occupied

783-488: A local glacial maximum in the region. In northeastern Italy , in the region around Lake Fimon , Artemisia -dominated semideserts, steppes, and meadow-steppes replaced open boreal forests at the start of the LGM, specifically during Heinrich Stadial 3. The overall climate of the region became both drier and colder. In the Sar Mountains , the glacial equilibrium-line altitude was about 450 metres lower than in

870-410: A mixture of grassland and tundra prevailed, and even here, the northern limit of tree growth was at least 20° farther south than today. In the period before the LGM, many areas that became completely 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 (BP,

957-514: A mixture of grassland and cool-weather alpine species. The biome has been called " Park Tundra ," "Arctic tundra," "Arctic pioneer vegetation," or “birch woodlands." It is now in the transition between taiga and tundra in Siberia . Then, it stretched from Siberia to Great Britain , in a more-or-less unbroken expanse. To the northwest was the Baltic ice lake , which was truncated by the edge of

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1044-428: A short-term increase in herbaceous pollen. The changed pollen pattern suggests an increased abundance of grass as well as a retreat of tree and shrubs. The change in vegetation distribution further indicates a colder and drier climate during this period. As for aquatic plant evidence, both aquatic and semi-aquatic botanical taxa show a sharp decrease, suggesting lower lake levels caused by a drier climate. The drier climate

1131-461: A slow change in vegetation towards a sparsely distributed vegetation dominated by Nothofagus species. Within this parkland vegetation Magellanic moorland alternated with Nothofagus forest, and as warming progressed even warm-climate trees began to grow in the area. It is estimated that the tree line was depressed about 1,000 m relative to present day elevations during the coldest period, but it rose gradually until 19,300 years ago. At that time

1218-482: Is a correlation between whether a British citizen considers themselves "British" or "European" and whether they live in an area which primarily supported Brexit . Derivatively, the adjective continental refers to the social practices or fashion of continental Europe. Examples include breakfast , topless sunbathing and, historically, long-range driving (before Britain had motorways ) often known as Grand Touring . Differences include electrical plugs, time zones for

1305-531: Is also reflected by increased salinity indicated by diatom analysis. The change in Chironomids population also indicates a colder climate. Microtendipes is an indicator of intermediate temperature in Late glacial deposits in northern Europe (Brooks and Birks, 2001). The abundance of Microtendipes peaked in the early part of Older Dryas suggesting a cold oscillation. The mollusc data ( Valvata piscinalis as

1392-637: Is referred to in Britain as the Dimlington Stadial , dated to between 31,000 and 16,000 years ago. The average global temperature about 21,000 years ago was about 6 °C (11 °F) colder than today. According to the United States Geological Survey (USGS), permanent summer ice covered about 8% of Earth's surface and 25% of the land area during the last glacial maximum. The USGS also states that sea level

1479-407: Is small enough to escape the resolution of most carbon-14 series, as the points are not close enough together to find the segment. One approach to the problem assigns a point and then picks an arbitrary segment. The Older Dryas is sometimes considered to be "centered" near 14,100 BP or to be 100 to 150 years long "at" 14,250 BP. A second approach finds carbon-14 or other dates as close to the end of

1566-610: Is that although the Scandinavian peninsula is attached to continental Europe, and accessible via a land route along the 66th parallel north , it is usually reached by sea. Kontinenten ("the Continent") is a vernacular Swedish expression that refers to an area excluding Sweden , Norway , and Finland but including Denmark (even the Danish Archipelago which is technically not a part of continental Europe) and

1653-471: Is the contiguous mainland of Europe , excluding its surrounding islands. It can also be referred to ambiguously as the European continent , – which can conversely mean the whole of Europe – and, by some, simply as the Continent . When Eurasia is regarded as a single continent, Europe is treated both as a continent and subcontinent . The continental territory of the historical Carolingian Empire

1740-675: The Baltic Shield , and in Russia in particular, the LGM ice margin of the Fennoscandian Ice Sheet was highly lobate. The main LGM lobes of Russia followed the Dvina , Vologda and Rybinsk basins respectively. Lobes originated as result of ice following shallow topographic depressions filled with a soft sediment substrate. The northern Ural region was covered in periglacial steppes. Permafrost covered Europe south of

1827-780: The Barents Sea , the Kara Sea , and Novaya Zemlya , ending at the Taymyr Peninsula in what is now northwestern Siberia. Warming commenced in northern latitudes around 20,000 years ago, but it was limited and considerable warming did not take place until around 14,600 year ago. In northwestern Russia , the Fennoscandian ice sheet reached its LGM extent approximately 17,000 years ago, about five thousand years later than in Denmark, Germany and Western Poland. Outside

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1914-614: The Cantabrian Mountains of the northwestern corner of the Iberian Peninsula , which in the present day have no permanent glaciers, the LGM led to a local glacial recession as a result of increased aridity caused by the growth of other ice sheets farther to the east and north, which drastically limited annual snowfall over the mountains of northwestern Spain. The Cantabrian alpine glaciers had previously expanded between approximately 60,000 and 40,000 years ago during

2001-632: The Cetacean Odontoceti , the Monodontidae : Delphinidae : Of the Mysticetian Eschrichtiidae : The top of the food chain was supported by larger numbers of smaller animals farther down, which lived in the herbaceous blanket covering the tundra or steppe and helped maintain it by carrying seeds, manuring and aerating it. Leporidae : Ochotonidae : Cricetidae : Sciuridae : Dipodidae : Eurasia

2088-772: The Gulf of Oman . Bathymetric data suggests there were two palaeo-basins in the Persian Gulf. The central basin may have approached an area of 20,000 km , comparable at its fullest extent to lakes such as Lake Malawi in Africa. Between 12,000 and 9,000 years ago much of the Gulf's floor was not covered by water, only being flooded by the sea after 8,000 years ago. It is estimated that annual average temperatures in Southern Africa were 6 °C lower than at present during

2175-617: The Hex River Mountains , in the Western Cape , block streams and terraces found near the summit of Matroosberg evidences past periglacial activity which likely occurred during the LGM. Palaeoclimatological proxies indicate the region around Boomplaas Cave was wetter, with increased winter precipitation. The region of the Zambezi River catchment was colder relative to present and the local drop in mean temperature

2262-676: The Last Glacial Coldest Period , was the most recent time during the Last Glacial Period where ice sheets were at their greatest extent 26,000 and 20,000 years ago. Ice sheets covered much of Northern North America , Northern Europe , and Asia and profoundly affected Earth 's climate by causing a major expansion of deserts, along with a large drop in sea levels. Based on changes in position of ice sheet margins dated via terrestrial cosmogenic nuclides and radiocarbon dating , growth of ice sheets in

2349-645: The Strait of Magellan suggest the peak in glacial surface area was constrained to between 25,200 and 23,100 years ago. There are no agreed dates for the beginning and end of the LGM, and researchers select dates depending on their criteria and the data set consulted. Jennifer French, an archeologist specialising in the European Palaeolithic, dates its onset at 27,500 years ago, with ice sheets at their maximum by around 26,000 years ago and deglaciation commencing between 20,000 and 19,000 years ago. The LGM

2436-519: The White Sea , a cooling occurred at 14,700–13,400/13,000, which resulted in a re-advance of the glacier in the initial Allerød. In Canada , the Shulie Lake phase, a re-advance, is dated to 14,000–13,500 BP. On the other hand, varve chronology in southern Sweden indicates a range of 14,050–13,900 BP. Northern Europe offered an alternation of steppe and tundra environments depending on

2523-723: The continental part of Greece (excluding the Aegean Islands , Crete , and the Ionian Islands ), the continental part of Italy (excluding Sardinia , Sicily , etc.), the continental part of Portugal (excluding the Azores and Madeira ), and the continental part of Spain (excluding the Balearic Islands , the Canary Islands , the plazas de soberanía , etc.). The term is used from the perspective of

2610-426: The permafrost line and the latitude . In moister regions, around lakes and streams, were thickets of dwarf birch , willow , sea buckthorn , and juniper . In the river valleys and uplands, to the south, were open birch forests. The first trees, birch and pine , had spread into Northern Europe 500 years earlier. During the Older Dryas, the glacier re-advanced, and the trees retreated southward, to be replaced by

2697-606: The Andes occupying lacustrine and marine basins where they spread out forming large piedmont glacier lobes . Glaciers extended about 7 km west of the modern Llanquihue Lake , but not more than 2 to 3 km south of it. Nahuel Huapi Lake in Argentina was also glaciated by the same time. Over most of the Chiloé Archipelago , glacier advance peaked 26,000 years ago, forming a long north–south moraine system along

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2784-515: The Arctic and Alpine plant Dryas octopetala , the remains of which are found in higher concentrations in deposits from colder periods. The Older Dryas was a variable cold, dry Blytt–Sernander period, observed in climatological evidence in only some regions, dependent on latitude. In regions in which it is not observed, the Bølling–Allerød is considered a single interstadial period. Evidence of

2871-548: The Bølling and the beginning of the Allerød as possible and then selects endpoints that are based on them: for example, 14,000–13,700 BP. The best approach attempts to include the Older Dryas in a sequence of points as close together as possible (high resolution) or within a known event. For example, pollen from the island of Hokkaidō , Japan , records a larch pollen peak and matching sphagnum decline at 14,600–13700 BP. In

2958-632: The Great Barrier Reef was enhanced due to low atmospheric CO 2 levels. The deep waters of the Indian Ocean were significantly less oxygenated during the LGM compared to the Middle Holocene. The deep South Indian Ocean in particular was an enormous carbon sink, partially explaining the very low p CO 2 of the LGM. The intermediate waters of the southeastern Arabian Sea were poorly ventilated relative to today because of

3045-550: The Holocene. In Greece , steppe vegetation predominated. Megafaunal abundance in Europe peaked around 27,000 and 21,000 BP; this bountifulness was attributable to the cold stadial climate. In Greenland, the difference between LGM temperatures and present temperatures was twice as great during winter as during summer. Greenhouse gas and insolation forcings dominated temperature changes in northern Greenland, whereas Atlantic meridional overturning circulation (AMOC) variability

3132-678: The LGM except in transient intervals around 23,200 and 22,300 BP. In the western South Atlantic , where Antarctic Intermediate Water forms, sinking particle flux was heightened as a result of increased dust flux during the LGM and sustained export productivity. The increased sinking particle flux removed neodymium from shallow waters, producing an isotopic ratio change. On the Island of Hawaii , geologists have long recognized deposits formed by glaciers on Mauna Kea during recent ice ages. The latest work indicates that deposits of three glacial episodes since 150,000 to 200,000 years ago are preserved on

3219-544: The LGM, 21,000 years ago, the sea level was about 125 meters (about 410 feet) lower than it is today. Across most of the globe, the hydrological cycle slowed down, explaining increased aridity in many regions of the world. In Africa and the Middle East, many smaller mountain glaciers formed, and the Sahara and other sandy deserts were greatly expanded in extent. The Atlantic deep sea sediment core V22-196, extracted off

3306-702: The Last Glacial Maximum. This temperature drop alone would however not have been enough to generate widespread glaciation or permafrost in the Drakensberg Mountains or the Lesotho Highlands . Seasonal freezing of the ground in the Lesotho Highlands might have reached depths of 2 meters or more below the surface. A few small glaciers did however develop during the LGM, in particular in south-facing slopes. In

3393-688: The Laurentide Ice Sheet reached 3.2 km in height around Keewatin Dome and about 1.7-2.1 km along the Plains divide. In addition to the large Cordilleran Ice Sheet in Canada and Montana , alpine glaciers advanced and (in some locations) ice caps covered much of the Rocky and Sierra Nevada Mountains further south. Latitudinal gradients were so sharp that permafrost did not reach far south of

3480-579: The Nordic archipelago, as well as nearby oceanic islands , including the Canary Islands , Madeira , the Azores , Iceland , the Faroe Islands , and Svalbard . The Scandinavian Peninsula is sometimes also excluded even though it is a part of "mainland Europe", as the de facto connections to the rest of the continent were historically across the Baltic Sea or North Sea (rather than via

3567-705: The North Atlantic was reduced, as measured by the increased proportion of radiogenic isotopes in neodymium isotope ratios. There is controversy whether upwelling off the Moroccan coast was stronger during the LGM compared to today. Though coccolith size increases in Calcidiscus leptoporus suggest stronger trade winds during the LGM caused there to be increased coastal upwelling of the northwestern coast of Africa, planktonic foraminiferal δ C records show upwelling and primary productivity were not enhanced during

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3654-465: The North Atlantic were better ventilated during the LGM by Glacial North Atlantic Intermediate Water (GNAIW) relative to its present-day ventilation by upper North Atlantic Deep Water (NADW). GNAIW was nutrient poor compared to present day upper NADW. Below GNAIW, southern source bottom water that was very rich in nutrients filled the deep North Atlantic. Due to the presence of immense ice sheets in Europe and North America, continental weathering flux into

3741-625: The Older Dryas event. Another study on an ocean sediment core from the Norwegian Trench also suggests a cooling between Bølling and Allerød warm phases. The glacial polar faunal study on ocean sediment core Troll 3.1 based on Neogloboquadrina pachyderma abundances suggests that there were two cooling events before Younger Dryas in which one of the events occurred within Bølling-Allerød interstadial and can be associated with Older Dryas. The study on late-glacial climate change in

3828-467: The Older Dryas is strongest in northern Eurasia, particularly part of Northern Europe , roughly equivalent to Pollen zone Ic. In the Greenland oxygen isotope record, the Older Dryas appears as a downward peak establishing a small, low-intensity gap between the Bølling and the Allerød. That configuration presents a difficulty in estimating its time, as it is more of a point than a segment. The segment

3915-577: The Rieme sites on the Great SandRidge of Maldegem-Stekene at Snellegem in NW Belgium, and many other sites in north-western Europe. δO measurements show a decreasing trend in δO at the transition to the Older Dryas, which corresponds to the ice core record of precipitation in the northern hemisphere. Pollen analysis shows a temporary decrease in the pollen levels of trees and shrubs with

4002-849: The Tatra Mountains. Older Dryas species are usually found in the sediment below the bottom layer of the bog. Indicator species are the Alpine plants: Grasslands species are the following: A well-stocked biozone prevailed on the Arctic plains and thickets of the Late Pleistocene. Plains mammals were most predominant: Artiodactyls : Perissodactyls : Proboscidea : So much meat on the hoof must have supported large numbers of Carnivora : Ursidae : Hyaenidae : Felidae : Canidae : Mustelidae : The sea also had its share of carnivores; their maritime location made them survive until modern times: Phocidae : Odobenidae : Of

4089-720: The White Mountains (New Hampshire, USA) refined the deglaciation history of the White Mountain Moraine System (WMMS) by mapping moraine belts and related lake sequences. The result suggests that the Littleton-Bethlehem (L-B) readvance of the ice sheet occurred between 14,000 and 13,800 years BP. The L-B readvance coincided with the Older Dryas events and provides the first well-documented and dated evidence of Older Dryas. Another Glacial chronology and palaeoclimate study on moraine suggests

4176-416: The atmosphere . The massive sheets of ice locked away water, lowering the sea level, exposing continental shelves , joining land masses together, and creating extensive coastal plains . The ice sheets also changed the atmospheric circulation, causing the northern Pacific and Atlantic oceans to cool and produce more clouds, which amplified the global cooling as the clouds reflected even more sunlight. During

4263-919: The best known being Lake Bonneville in Utah . This also occurred in Afghanistan and Iran , where a major lake formed in the Dasht-e Kavir . In Australia , shifting sand dunes covered half the continent, while the Chaco and Pampas in South America became similarly dry. Present-day subtropical regions also lost most of their forest cover, notably in eastern Australia, the Atlantic Forest of Brazil , and southern China , where open woodland became dominant due to much drier conditions. In northern China – unglaciated despite its cold climate –

4350-507: The changing abundance pattern of fauna and flora are most commonly used when examining lake sediments. Moraine belts are usually studied in places with palaeoglacier presented. As for ocean sediments, the variations of alkenone levels and faunal abundances were measured to model paleotemperatures in separate studies shown in the following sections. The North Greenland Ice Core Project (GRIP) members drilled an undisturbed ice core from North Greenland (75.1 8N, 42.3 8W). The ice core record showed

4437-402: The coast of Senegal, shows a major southward expansion of the Sahara. The Persian Gulf averages about 35 metres in depth and the seabed between Abu Dhabi and Qatar is even shallower, being mostly less than 15 metres deep. For thousands of years the Ur-Shatt (a confluence of the Tigris - Euphrates Rivers ) provided fresh water to the Gulf, as it flowed through the Strait of Hormuz into

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4524-420: The continents: the Indonesian islands as far east as Borneo and Bali were connected to the Asian continent in a landmass called Sundaland . Palawan was also part of Sundaland, while the rest of the Philippine Islands formed one large island separated from the continent only by the Sibutu Passage and the Mindoro Strait . The environment along the coast of South China was not very different from that of

4611-466: The east and west extremities of the Sundaland shelf. Only in Central America and the Chocó region of Colombia did tropical rainforests remain substantially intact – probably due to the extraordinarily heavy rainfall of these regions. Most of the world's deserts expanded. Exceptions were in what is the present-day Western United States , where changes in the jet stream brought heavy rain to areas that are now desert and large pluvial lakes formed,

4698-491: The eastern coast of Chiloé Island (41.5–43° S). By that time the glaciation at the latitude of Chiloé was of ice sheet type contrasting to the valley glaciation found further north in Chile. Despite glacier advances much of the area west of Llanquihue Lake was still ice-free during the Last Glacial Maximum. During the coldest period of the Last Glacial Maximum vegetation at this location was dominated by Alpine herbs in wide open surfaces. The global warming that followed caused

4785-405: The estimated ages can vary using different age dating methods. Numerous studies on chronology and palaeoclimate of last deglaciation show a cooling event within Bølling–Allerød warming that reflects the occurrence of Older Dryas. The determination of paleotemperatures varies from study to study depending on the sample collected. δO measurements are most common when analyzing Ice core samples whereas

4872-505: The glacier. Species had access to Denmark and southern Sweden. Most of Finland and the Baltic countries were under the ice or the lake for most of the period. Northern Scandinavia was glaciated. Between Britain and Continental Europe were rolling hills prolifically populated with animals. Thousands of specimens, hundreds of tons of bones, have been recovered from the bottom of the North Sea , called " Doggerland ," and they continue to be recovered. There are many more species found for

4959-581: The ice sheet down to as far south as present-day Szeged in Southern Hungary. Ice covered the whole of Iceland . In addition, ice covered Ireland along with roughly the northern half of the British Isles with the southern boundary of the ice sheet running approximately from the south of Wales to the north east of England, and then across the now submerged land of Doggerland to Denmark . Central Europe had isolated pockets of relative warmth corresponding to hydrothermally active areas, which served as refugia for taxa not adapted to extremely cold climates. In

5046-421: The ice sheets except at high elevations. Glaciers forced the early human populations who had originally migrated from northeast Siberia into refugia , reshaping their genetic variation by mutation and drift . This phenomenon established the older haplogroups found among Native Americans , and later migrations are responsible for northern North American haplogroups. In southeastern North America, between

5133-499: The lengthy land route that involves travelling to the north of the peninsula where it meets Finland, and then south through northeast Europe). The Øresund Bridge now links the Scandinavian road and rail networks to those of Western Europe. In both Great Britain and Ireland, the Continent is widely and generally used to refer to the mainland of Europe. An amusing British newspaper headline supposedly once read, "Fog in Channel ; Continent Cut Off". It has also been claimed that this

5220-464: The lowlands and Northern Germany before the Older Dryas. During the Older Dryas, contemporaneous with the Havelte Group of the late Hamburgian, the Federmesser culture appeared and occupied Denmark and southern Sweden, following the reindeer. South of the Hamburgian was the longstanding Magdalenian . In Ukraine was the Moldovan, which used tusks to build shelters. Last Glacial Maximum The Last Glacial Maximum ( LGM ), also referred to as

5307-592: The most part, the use of left-hand traffic , and for the United Kingdom, currency and the continued use of certain imperial units alongside the metric units which have long since displaced customary units in continental Europe. Britain is physically connected to continental Europe through the undersea Channel Tunnel (the longest undersea tunnel in the world), which accommodates both the Eurotunnel Shuttle (passenger and vehicle use – vehicle required) and Eurostar (passenger use only) services. These services were established to transport passengers and vehicles through

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5394-412: The north, in the dry Andes of Central and the Last Glacial Maximum is associated with increased humidity and the verified advance of at least some mountain glaciers. Montane glaciers in the northern Andes reached their peak extent approximately 27,000 years ago. In northwestern Argentina, pollen deposits record the altitudinal descent of the treeline during the LGM. Amazonia was much drier than in

5481-428: The past. During the Last Glacial Maximum, much of the world was cold, dry, and inhospitable, with frequent storms and a dust-laden atmosphere. The dustiness of the atmosphere is a prominent feature in ice cores; dust levels were as much as 20 to 25 times greater than they are in the present. This was probably due to a number of factors: reduced vegetation, stronger global winds, and less precipitation to clear dust from

5568-413: The period than in this article. Most families were more diverse than they are today, and they were yet more so in the last interglacial. A great extinction , especially of mammals, continued throughout the end of the Pleistocene , and it may be continuing today. The Older Dryas is a period of cooling during the Bølling–Allerød warming , estimated to be from 13,900 to 13,600 years before present (BP), and

5655-654: The persistence of rainforests in eastern Australia at this time. Rivers maintained their sinuous form in southeastern Australia and there was increased aeolian deposition of sediment in compared to today. The Flinders Ranges likewise experienced humid conditions. In southwestern Western Australia, forests disappeared during the LGM. Between Sahul and Sundaland – a peninsula of South East Asia that comprised present-day Malaysia and western and northern Indonesia – there remained an archipelago of islands known as Wallacea . The water gaps between these islands, Sahul and Sundaland were considerably narrower and fewer in number than in

5742-744: The present day, featuring moist subtropical evergreen forests, despite sea levels in the South China Sea being about 100 metres lower than the present day. The Australian mainland, New Guinea , Tasmania and many smaller islands comprised a single land mass. This continent is now referred to sometimes as Sahul . In the Bonaparte Gulf of northwestern Australia, sea levels were about 125 metres lower than present. Interior Australia saw widespread aridity, evidenced by extensive dune activity and falling lake levels. Eastern Australia experienced two nadirs in temperature. Lacustrine sediments from North Stradbroke Island in coastal Queensland indicated humid conditions. Data from Little Llangothlin Lagoon likewise indicate

5829-507: The present day. The two main islands of New Zealand, along with associated smaller islands, were joined as one landmass. Virtually all of the Southern Alps were under permanent ice cover, with alpine glaciers extending from them into much of the surrounding high country . Northern Europe was largely covered by ice, with the southern boundary of the ice sheets passing through Germany and Poland. This ice extended northward to cover Svalbard and Franz Josef Land and northeastward to occupy

5916-498: The present, with flora diminished to almost the same degree as in glaciated areas of Europe and North America. Even in less affected regions, rainforest cover was greatly diminished, especially in West Africa where a few refugia were surrounded by tropical grasslands . The Amazon rainforest was split into two large blocks by extensive savanna , and the tropical rainforests of Southeast Asia probably were similarly affected, with deciduous forests expanding in their place except on

6003-485: The present. δ D values from plant waxes from the LGM are significantly more enriched than those in the present and those dating back to MIS 3, evidencing this increased aridity. Eastern Brazil was also affected; the site of Guanambi in Bahia was much drier than today. AMOC was weaker and more shallow during the LGM. Sea surface temperatures in the western subtropical gyre of the North Atlantic were around 5 °C colder compared to today. Intermediate depth waters of

6090-448: The rest of continental Europe. In Norway, similarly, one speaks about Kontinentet as a separate entity. In Denmark, Jutland is referred to as the mainland and thereby a part of continental Europe. The Scandinavian Peninsula is now connected to the Danish mainland (the Jutland Peninsula ) by several bridges and tunnels. The Continent may sometimes refer to the continental part of France (excluding Corsica and overseas France ),

6177-407: The shutting down of the Oyashio Current and the presence of large east–west mountain ranges were secondary factors that prevented the development of continental glaciation in Asia . All over the world, climates at the Last Glacial Maximum were cooler and almost everywhere drier. In extreme cases, such as South Australia and the Sahel , rainfall could have been diminished by up to 90% compared to

6264-606: The southern Appalachian Mountains and the Atlantic Ocean, there was an enclave of unusually warm climate. In the Southern Hemisphere, the Patagonian Ice Sheet covered the whole southern third of Chile and adjacent areas of Argentina. On the western side of the Andes the ice sheet reached sea level as far north as in the 41 degrees south at Chacao Channel . The western coast of Patagonia

6351-502: The southern hemisphere commenced 33,000 years ago and maximum coverage has been estimated to have occurred sometime between 26,500 years ago and 20,000 years ago. After this, deglaciation caused an abrupt rise in sea level. Decline of the West Antarctica ice sheet occurred between 14,000 and 15,000 years ago, consistent with evidence for another abrupt rise in the sea level about 14,500 years ago. Glacier fluctuations around

6438-645: The tunnel on a 24/7 basis between England and continental Europe, while still maintaining passport and immigration control measures on both sides of the tunnel. This route is popular with refugees and migrants seeking to enter the UK. Especially in Germanic studies , continental refers to the European continent excluding the Scandinavian Peninsula , Britain, Ireland, and Iceland. The reason for this

6525-569: The volcano. Glacial moraines on the volcano formed about 70,000 years ago and from about 40,000 to 13,000 years ago. If glacial deposits were formed on Mauna Loa , they have long since been buried by younger lava flows. Low sea surface temperature (SST) and sea surface salinity (SSS) in the East China Sea during the LGM suggests the Kuroshio Current was reduced in strength relative to the present. Abyssal Pacific overturning

6612-618: The weakened thermohaline circulation. Evidence from sediment cores in the Scotia Sea suggests the Antarctic Circumpolar Current was weaker during the LGM than during the Holocene. The Antarctic Polar Front (APF) was located much farther to the north compared to its present-day location. Studies suggest it could have been placed as far north as 43°S, reaching into the southern Indian Ocean. Continental Europe Continental Europe or mainland Europe

6699-629: Was a pocket of relative warmth. Following a preceding period of relative retreat from 52,000 to 40,000 years ago, the Laurentide Ice Sheet grew rapidly at the onset of the LGM until it covered essentially all of Canada east of the Rocky Mountains and extended roughly to the Missouri and Ohio Rivers , and eastward to Manhattan , reaching a total maximum volume of around 26.5 to 37 million cubic kilometres. At its peak,

6786-490: Was a regular weather forecast in Britain in the 1930s. In addition, the word Europe itself is also regularly used to mean Europe excluding the islands of Great Britain, Iceland, and Ireland (although the term is often used to refer to the European Union ). The term mainland Europe is also sometimes used. Usage of these terms may reflect political or cultural allegiances, for example it has been observed that there

6873-750: Was about 125 meters (410 ft) lower than in present times (2012). When comparing to the present, the average global temperature was 15 °C (59 °F) for the 2013–2017 period. As of 2012 about 3.1% of Earth's surface and 10.7% of the land area is covered in year-round ice. Carbon sequestration in the highly stratified and productive Southern Ocean was essential in producing the LGM. The formation of an ice sheet or ice cap requires both prolonged cold and precipitation ( snow ). 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

6960-565: Was because the ice sheets in Europe produced extensive anticyclones above them. 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 (except in Kamchatka where these westerly winds lifted moisture from the Sea of Japan ). The relative warmth of the Pacific Ocean due to

7047-486: Was largely glaciated, but some authors have pointed out the possible existence of ice-free refugia for some plant species. On the eastern side of the Andes, glacier lobes occupied the depressions of Seno Skyring , Seno Otway , Inútil Bay , and Beagle Channel . On the Straits of Magellan, ice reached as far as Segunda Angostura . During the LGM, valley glaciers in the southern Andes (38–43° S) merged and descended from

7134-518: Was one of the many old cultural concepts used for mainland Europe . This was consciously invoked in the 1950s as one of the basis for the prospective European integration (see also multi-speed Europe ) The most common definition of mainland Europe excludes these continental islands : the Greek islands , Cyprus , Malta , Sicily , Sardinia , Corsica , the Balearic Islands , Great Britain and Ireland and surrounding islands, Novaya Zemlya and

7221-643: Was populated by Homo sapiens sapiens ( Cro-Magnon man ) during the late Upper Paleolithic . Bands of humans survived by hunting the mammals of the plains. In the Northern Europe they preferred reindeer, in Ukraine the woolly mammoth . They sheltered in huts and manufactured tools around campfires. Ukrainian shelters were supported by mammoth tusks. Humans were already established across Siberia and North America. Two domestic dogs ( Canis familiaris ) have been found in late Pleistocene Ukraine and were

7308-793: Was seasonally uniform. On the island of Mauritius in the Mascarenhas Archipelago , open wet forest vegetation dominated, contrasting with the dominantly closed-stratified-tall-forest state of Holocene Mauritian forests. There were ice sheets in modern Tibet (although scientists continue to debate the extent to which the Tibetan Plateau was covered with ice) as well as in Baltistan and Ladakh . In Southeast Asia , many smaller mountain glaciers formed, and permafrost covered Asia as far south as Beijing . Because of lowered sea levels, many of today's islands were joined to

7395-570: Was similar in spatial extent. The outflow of North Pacific Intermediate Water through the Tasman Sea was stronger during the LGM. In the Great Barrier Reef along the coast of Queensland , reef development shifted seaward due to the precipitous drop in sea levels, reaching a maximum distance from the present coastline as sea levels approached their lowest levels around 20,700-20,500 years ago. Microbial carbonate deposition in

7482-505: Was the dominant influence on southern Greenland's climate. Illorsuit Island was exclusively covered by cold-based glaciers. Eastern Beringia was extremely cold and dry. July air temperatures in northern Alaska and Yukon were about 2-3 °C lower compared to today. Equilibrium line altitudes in Alaska suggest summer temperatures were 2-5 °C compared to preindustrial. Sediment core analysis from Lone Spruce Pond in southwestern Alaska show it

7569-526: Was weaker during the LGM than in the present day, although it was temporarily stronger during some intervals of ice sheet retreat. The El Niño–Southern Oscillation (ENSO) was strong during the LGM. Evidence suggests that the Peruvian Oxygen Minimum Zone in the eastern Pacific was weaker than it is in the present day, likely as a result of increased oxygen concentrations in seawater permitted by cooler ocean water temperatures, though it

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