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49-596: The NGRIP record helps to resolve a problem with the GRIP and GISP2 records – the unreliability of the Eemian Stage portion of the record. NGRIP covers 5 kyr of the Eemian, and shows that temperatures then were roughly as stable as the pre-industrial Holocene temperatures were. This is confirmed by sediment cores, in particular MD95-2042. In 2003, NGRIP recovered what seem to be plant remnants nearly two miles below

98-645: A catastrophic erosion and flood event. Consequently the ice-age-muted flows from the Thames and Scheldt flowed through the gap into the English Channel/Inlet, but the Meuse and Rhine still flowed without any significant link to the inlet (such as today's IJssel distributary supports). In a second flood about 225,000 years ago supported by glaciers extending from areas then land such as the Zuiderzee ,

147-694: A dam from Scandinavia to Scotland, and the Rhine, combined with the Thames and drainage from much of north Europe , created a vast lake behind the dam, which eventually spilled over the Weald into the English Channel. This overflow followed by further scouring became recognisably the Short Straits (an alternative name for this strait) about 425,000 years ago. A narrow deep channel along the middle of

196-671: A land bridge that linked the Weald in Great Britain to the Boulonnais in the Pas de Calais . Though pitted by troughs and rivers, the English Channel was almost mainly land at the height of the last ice age. The predominant geology of both and of the seafloor is chalk . Although somewhat resistant to erosion, erosion of both coasts has created the famous white cliffs of Dover in the UK and

245-626: A result of mixing of Last Interglacial ice with ice from the preceding or succeeding glacial intervals. The warmest peak of the Last Interglacial was around 125,000 years ago, when forests reached as far north as North Cape, Norway (which is now tundra ) well above the Arctic Circle at 71°10′21″N 25°47′40″E  /  71.17250°N 25.79444°E  / 71.17250; 25.79444 . Hardwood trees such as hazel and oak grew as far north as Oulu , Finland. At

294-567: Is a transition zone for the species of the Atlantic Ocean and those of the southern part of the North Sea. This mix of various environments promotes a wide variety of wildlife. The Ridens de Boulogne , a 10–20 m (33–66 ft) deep rocky shoal, partially sand-capped,15 nmi (28 km; 17 mi) west of Boulogne , boasts the highest profusion of maerl in the strait. Thus some 682 km (263 sq mi) of

343-518: Is given by Lorié (1887), and Spaink (1958). Since their discovery, Last Interglacial beds in the Netherlands have mainly been recognized by their marine molluscan content combined with their stratigraphical position and other palaeontology. The marine beds there are often underlain by tills that are considered to date from the Saalian , and overlain by local fresh water or wind-blown deposits from

392-591: Is located. Harting noticed the marine molluscan assemblages to be very different from the modern fauna of the North Sea . Many species from the Last Interglacial layers nowadays show a much more southern distribution, ranging from South of the Strait of Dover to Portugal ( Lusitanian faunal province) and even into the Mediterranean (Mediterranean faunal province). More information on the molluscan assemblages

441-584: Is provided by Bosch, Cleveringa and Meijer, 2000. The Last Interglacial climate is believed to have been warmer than the current Holocene. The temperature of the Last Interglacial peaked during the early part of the period, around 128,000 to 123,000 years Before Present , before declining during the latter half of the period. Changes in the Earth's orbital parameters from today (greater obliquity and eccentricity, and perihelion), known as Milankovitch cycles , probably led to greater seasonal temperature variations in

490-730: Is within the territorial waters of France and the United Kingdom, but a right of transit passage under the United Nations Convention on the Law of the Sea allows vessels of other nations to move freely through the strait. On a clear day, it is possible to see the opposite coastline of England from France and vice versa with the naked eye, with the most famous and obvious sight being the White Cliffs of Dover from

539-518: The American lion ( Panthera atrox ) appeared and become widespread across North America, having descended from populations of the Eurasian cave lion ( Panthera spelaea ) that had migrated into Alaska during the preceding Penultimate Glacial Period. The range of cold-adapted taxa like the woolly mammoth ( Mammuthus primigenius ) contracted towards refugia . Neanderthals managed to colonise

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588-677: The Atlantic via the Pentland Firth in the last glaciation (of over 300,000 years) is a necessary pre-condition for the relatively late cutting through of the Strait to the south. Likewise, a 2007 study concluded that the Strait was formed by erosion caused by two major floods. The first was about 425,000 years ago, when an ice-dammed lake in the southern North Sea overflowed and broke the Weald- Artois (Boulonnais) chalk range in

637-592: The Canadian Arctic Archipelago : currently, the northern limit is further south at Kuujjuaq in northern Quebec . Coastal Alaska was warm enough during the summer due to reduced sea ice in the Arctic Ocean to allow Saint Lawrence Island (now tundra) to have boreal forest, although inadequate precipitation caused a reduction in the forest cover in interior Alaska and Yukon Territory despite warmer conditions. The prairie-forest boundary in

686-700: The Cap Blanc Nez in France. The Channel Tunnel was bored through solid chalk – compacted remains of sea creatures and marine- deposited , ground up calciferous rock/soil debris. The Rhine (as the Urstrom ) flows northeast into the North Sea as the sea (covering most of the Netherlands) fell during the start of the first of the Pleistocene Ice Ages . The new ice unusually created

735-669: The Eemian , was the interglacial period which began about 130,000 years ago at the end of the Penultimate Glacial Period and ended about 115,000 years ago at the beginning of the Last Glacial Period . It corresponds to Marine Isotope Stage 5e . It was the second-to-latest interglacial period of the current Ice Age, the most recent being the Holocene which extends to the present day (having followed

784-748: The Great Plains of the United States lay further west near Lubbock, Texas , whereas the current boundary is near Dallas . Interglacial conditions ended on Antarctica while the Northern Hemisphere was still experiencing warmth. Sea level at peak was probably 6 to 9 metres (20 to 30 feet) higher than today, with Greenland contributing 0.6 to 3.5 m (2.0 to 11.5 ft), thermal expansion and mountain glaciers contributing up to 1 m (3.3 ft), and an uncertain contribution from Antarctica. A 2007 study found evidence that

833-594: The North Atlantic Current , lasting hundreds of years and causing temperature drops of a few degrees and vegetation changes in these regions. In Northern Europe, winter temperatures rose over the course of the Last Interglacial while summer temperatures fell. During an insolation maximum from 133,000 to 130,000 BP, meltwater from the Dnieper and Volga caused the Black and Caspian Seas to connect. During

882-525: The Weichselian . In contrast to e.g. the deposits in Denmark, the Last Interglacial deposits in the type area have never been found overlain by tills, nor in ice-pushed positions. Van Voorthuysen (1958) described the foraminifera from the type site, whereas Zagwijn (1961) published the palynology , providing a subdivision of this stage into pollen stages. At the end of the 20th century, the type site

931-484: The global wave of megafauna extinctions that occurred during the following Last Glacial Period, has been suggested as a "baseline" reference point for the analysis and restoration of modern European ecosystems. Following the melting of the Laurentide Ice Sheet , a number of North American megafauna species migrated northwards to inhabit northern Canada and Alaska during the Last Interglacial, including

980-485: The last glacial period ). During the Last Interglacial, the proportion of CO 2 in the atmosphere was about 280 parts per million. The Last Interglacial was one of the warmest periods of the last 800,000 years, with temperatures comparable to and at times warmer (by up to on average 2 degrees Celsius) than the contemporary Holocene interglacial, with the maximum sea level being up to 6 to 9 metres higher than at present, with global ice volume likely also being smaller than

1029-647: The Alps, conditions were 1–2 °C cooler than today. The model (generated using observed greenhouse gas concentrations and Last Interglacial orbital parameters) generally reproduces these observations, leading them to conclude that these factors are enough to explain the Last Interglacial temperatures. Meltwater pulse 2B, approximately 133,000 BP, substantially weakened the Indian Summer Monsoon (ISM). Trees grew as far north as southern Baffin Island in

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1078-490: The American camel Camelops hesternus , mastodons (genus Mammut ) the large ground sloth Megalonyx jeffersonii , and the bear sized giant beaver Castoroides , with the lower latitudes of Canada being inhabited (in addition to the aformentioned taxa) by species like Columbian mammoth ( Mammuthus columbi ), stag-moose ( Cervalces ), and the llama Hemiauchenia . The steppe bison ( Bison priscus ) migrated into

1127-673: The Channel and the North Sea , and separating Great Britain from continental Europe . The shortest distance across the strait, at approximately 20 miles (32 kilometres), is from the South Foreland , northeast of Dover in the English county of Kent , to Cap Gris Nez , a cape near to Calais in the French département of Pas-de-Calais . Between these points lies the most popular route for cross-channel swimmers . The entire strait

1176-411: The Channel floor, "100m deep" and in places "several kilometres in diameter", to lake water plunging over a rock ridge causing isolated depressions or plunge pools . The melting ice and rising sea levels submerged Doggerland , the area linking Britain to France, around 6,500–6,200 BCE. The Lobourg strait, the deepest part the strait, runs its 6 km (4 mi)wide slash on a NNE–SSW axis. Nearer to

1225-615: The French coast than to the English, it borders the Varne sandbank (shoals) where it plunges to 68 m (223 ft) and further south, the Ridge bank (shoals) (French name " Colbart " ) with a maximum depth of 62 m (203 ft). The depth of the strait varies between 68 m (223 ft) at the Lobourg strait and 20 m (66 ft) at the highest banks. The seabed forms successions of three habitats: The strong tidal currents of

1274-489: The French coastline and shoreline buildings on both coastlines, as well as lights on either coastline at night, as in Matthew Arnold 's poem " Dover Beach ". Most maritime traffic between the Atlantic Ocean and the North Sea and Baltic Sea passes through the Strait of Dover, rather than taking the longer and more dangerous route around the north of Scotland. The strait is one of the busiest international seaways in

1323-604: The Greenland ice core site Dye 3 was glaciated during the Last Interglacial, which implies that Greenland could have contributed at most 2 m (6.6 ft) to sea level rise . Recent research on marine sediment cores offshore of the West Antarctic Ice Sheet suggest that the sheet melted during the Last Interglacial, and that ocean waters rose as fast as 2.5 meters per century. Global mean sea surface temperatures are thought to have been higher than in

1372-1039: The Holocene interglacial. The Last Interglacial is known as the Eemian in northern Europe (sometimes used to describe the global interglacial), Ipswichian in Britain, the Mikulino (also spelled Milukin) interglacial in Russia, the Kaydaky in Ukraine, the Valdivia interglacial in Chile , and the Riss-Würm interglacial in the Alps . Depending on how a specific publication defines the Sangamonian Stage of North America,

1421-546: The Holocene, but not by enough to explain the rise in sea level through thermal expansion alone, and so melting of polar ice caps must also have occurred. Because of the sea level drop since the Last Interglacial, exposed fossil coral reefs are common in the tropics, especially in the Caribbean and along the Red Sea coastlines. These reefs often contain internal erosion surfaces showing significant sea level instability during

1470-638: The Last Interglacial is equivalent to either all or part of it. The period falls into the Middle Paleolithic and is of some interest for the evolution of anatomically modern humans , who were present in Western Asia ( Skhul and Qafzeh hominins ) as well as in Southern Africa by this time, representing the earliest split of modern human populations that persists to the present time (associated with mitochondrial haplogroup L0 ). As

1519-691: The Last Interglacial. Along the Central Mediterranean Spanish coast, sea levels were comparable to those of the present. Scandinavia formed an island due to the area between the Gulf of Finland and the White Sea being drowned. Vast areas of northwestern Europe and the West Siberian Plain were inundated. The warmness of the interval allowed temperate-adapted taxa to extend their range considerably northward, with

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1568-635: The Meuse and Rhine were ice-dammed into a lake that broke catastrophically through a high weak barrier (perhaps chalk, or an end-moraine left by the ice sheet). Both floods cut massive flood channels in the dry bed of the English Channel, somewhat like the Channeled Scablands or the Wabash River in the USA. A further update in 2017 attributed a series of previously described underwater holes in

1617-549: The Northern Hemisphere. As the Last Interglacial cooled, p CO 2 remained stable. During the northern summer, temperatures in the Arctic region were about 2–4 °C higher than in 2011. The Arctic Last Interglacial climate was highly unstable, with pronounced temperature swings revealed by δ O fluctuations in Greenlandic ice cores, though some of the instability inferred from Greenland ice core project records may be

1666-637: The heartlands of North America from Alaska at the beginning of the Last Interglacial, giving rise to the giant long-horned bison Bison latifrons (which is first known from the Snowmass site in Colorado, dating to around 120,000 years ago) and ultimately all North American bison species, and marking the beginning of the Rancholabrean faunal age in North America. Also during this time period

1715-448: The higher latitudes of Europe during this time interval, after having retreated from the region due to unfavourable conditions during the Penultimate Glacial Period. However, unlike previous interglacials, they were absent from Britain, likely due to Britain being an island during this time. During the Last Interglacial, Neanderthals engaged in a variety of food-gathering activities, including fishing, as well as big-game hunting, including

1764-400: The largest animals living in Europe at the time, straight-tusked elephants. Modern humans were present outside Africa in Arabia during this interval, as far east as the Persian Gulf . Strait of Dover The Strait of Dover or Dover Strait , historically known as the Dover Narrows , is the strait at the narrowest part of the English Channel , marking the boundary between

1813-401: The middle of the Last Interglacial, a weakened Atlantic Meridional Overturning Circulation (AMOC) began to cool the eastern Mediterranean region. The period closed as temperatures steadily fell to conditions cooler and drier than the present, with a 468-year-long aridity pulse in central Europe at about 116,000 BC, and by 112,000 BC, ice caps began to form in southern Norway, marking

1862-402: The most recent point in time with a climate comparable to the Holocene, the Last Interglacial is also of relevance as a point of reference ( baseline ) for nature conservation. The Last Interglacial was first recognized from boreholes in the area of the city of Amersfoort , Netherlands , by Pieter Harting (1875). He named the beds "Système Eémien", after the river Eem on which Amersfoort

1911-424: The only route across it except for air transport. The Channel Tunnel now provides an alternative route, crossing beneath the strait at an average depth of 45 m (148 ft) below the seabed. The town of Dover gives its name to one of the sea areas of the British Shipping Forecast . The formation of strait was through scouring by erosion . It had for many millennia (since the last warm interglacial ) been

1960-526: The peak of the Last Interglacial, the Northern Hemisphere winters were generally warmer and wetter than now, though some areas were actually slightly cooler than today. A cooling event similar to but not exactly mirroring the 8.2-kiloyear event is recorded from Beckentin during the E5 phase of the Eemian, some 6,290 years after the start of interglacial afforestation. A 2018 study based on soil samples from Sokli in northern Finland identified abrupt cold spells ca. 120,000 years ago caused by shifts in

2009-987: The range of the hippopotamus ( Hippopotamus amphibius ) notably extending as far north as North Yorkshire in northern England, though their range outside of southern Europe did not extend much further east of than the Rhine . The temperate landscapes of Europe were inhabited by large now extinct megafauna including the straight-tusked elephant ( Palaeoloxodon antiquus ), the narrow-nosed rhinoceros ( Stephanorhinus hemitoechus ), Merck's rhinoceros ( Stephanorhinus kirchbergensis ), Irish elk ( Megaloceros giganteus ) and aurochs ( Bos primigenius ), alongside still-living species like red deer ( Cervus elaphus ), fallow deer ( Dama dama ), roe deer ( Capreolus capreolus ) and wild boar ( Sus scrofa ), with predators including lions (the extinct Panthera spelaea ) and cave hyenas ( Crocuta ( Crocuta ) spelaea ), brown bears ( Ursus arctos ) and wolves ( Canis lupus ). The Last Interglacial ecosystems of Europe, which existed prior to

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2058-405: The start of a new glacial period . The Eemian lasted about 1,500 to 3,000 years longer in Southern Europe than in Northern Europe. Kaspar et al. (GRL, 2005) performed a comparison of a coupled general circulation model (GCM) with reconstructed Last Interglacial temperatures for Europe. Central Europe (north of the Alps) was found to be 1–2 °C (1.8–3.6 °F) warmer than present; south of

2107-411: The strait at depth slow around its rocky masses as these stimulate countercurrents and deep, calm pockets where many species can find shelter. In these calmer lee zones, the water is clearer than in the rest of the strait; thus algae can grow despite the 46 m (151 ft) average depth. They help increase diversity in the local species – some of which are endemic to the strait. Moreover, this

2156-674: The strait is classified as a Natura 2000 protection zone named Ridens et dunes hydrauliques du Pas de Calais (Ridens and sub-aqueous dunes of the Dover Strait). This includes the sub-aqueous dunes of Varne, Colbart, Vergoyer and Bassurelle, the Ridens de Boulogne , and the Lobourg channel which provides calmer and clearer waters due to its depth reaching 68 m (223 ft). Many crossings other than in conventional vessels have been attempted, including by pedalo , jetpack , bathtub , amphibious vehicle and more commonly by swimming . Since French law bans many of them, unlike English law , most such crossings originate in England. In

2205-414: The strait is the remnants of the main (summer) outflow of the northern Ustrom glacial lake (a collect for other then-seasonal rivers, in winter iced up, such as the Thames and Weser) in the last Ice Age . A deposit in East Anglia marks the old preglacial northward course of the Urstrom-Thames when it also drained Doggerland . The deep sea floor east of Lincolnshire and East Yorkshire , connecting to

2254-467: The surface, and they may be several million years old. "Several of the pieces look very much like blades of grass or pine needles," said University of Colorado at Boulder geological sciences Professor James White, an NGRIP principal investigator. "If confirmed, this will be the first organic material ever recovered from a deep ice-core drilling project," he said. The original web page of the NGRIP project with field diaries and pictures. The NGRIP project

2303-449: The world, used by over 400 commercial vessels daily. This has made traffic safety a critical issue, with HM Coastguard and the Maritime Gendarmerie maintaining a 24-hour watch over the strait and enforcing a strict regime of shipping lanes . In addition to the intensive north-east to south-west traffic, the strait is crossed from north-west to south-east by ferries linking Dover to Calais and Dunkirk . Until 1994 these provided

2352-488: Was re-investigated using old and new data in a multi-disciplinary approach (Cleveringa et al., 2000). At the same time a parastratotype was selected in the Amsterdam glacial basin in the Amsterdam-Terminal borehole and was the subject of a multidisciplinary investigation (Van Leeuwen, et al., 2000). These authors also published a U/Th age for late Last Interglacial deposits from this borehole of 118,200 ± 6,300 years ago. A historical review of Dutch Last Interglacial research

2401-437: Was run by an international consortium of scientists, and drilling and logistics were managed by what is now called Centre for Ice and Climate at the Niels Bohr Institute, University of Copenhagen, Denmark. This research centre maintains a web page about ice core research: 75°01′N 42°32′W  /  75.017°N 42.533°W  / 75.017; -42.533 Eemian Stage The Last Interglacial , also known as

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