Central Europe (north of the Alps) was found to be 1–2 ☌ (1.8–3.6 ☏) warmer than present south of the Alps, conditions were 1–2 ☌ cooler than today. (GRL, 2005) performed a comparison of a coupled general circulation model (GCM) with reconstructed Eemian temperatures for Europe. 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, a glacial period had returned. The prairie-forest boundary in the Great Plains of the United States lay further west near Lubbock, Texas, whereas the current boundary is near Dallas. 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.
Trees grew as far north as southern Baffin Island in the Canadian Arctic Archipelago: currently, the northern limit is further south at Kuujjuaq in northern Quebec. The hippopotamus was distributed as far north as the rivers Rhine and Thames. Hardwood trees such as hazel and oak grew as far north as Oulu, Finland.Īt the peak of the Eemian, the Northern Hemisphere winters were generally warmer and wetter than now, though some areas were actually slightly cooler than today. The warmest peak of the Eemian 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☁0′21″N 25☄7′40″E / 71.17250°N 25.79444☎ / 71.17250 25.79444. During summer months, temperatures in the Arctic region were about 2-4 ☌ higher than today. 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 the Northern Hemisphere. The Eemian climate is believed to have been warmer than the current Holocene. View of the Eemian-aged coastal terraces of Niebla near Valdivia, Chile. 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). Depending on how a specific publication defines the Sangamonian Stage of North America, the Eemian is equivalent to either all or part of it.
The Eemian is known as the Ipswichian in the UK, the Mikulin interglacial in Russia, the Valdivia interglacial in Chile and the Riss-Würm interglacial in the Alps. During the Eemian, the proportion of CO 2 in the atmosphere was about 280 parts per million. The prevailing Eemian climate was, on average, around 1 to 2 degrees Celsius (1.8 to 3.6 Fahrenheit) warmer than that of the Holocene. Although sometimes referred to as the "last interglacial" (in the "most recent previous" sense of "last"), 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 the last glacial period). It corresponds to Marine Isotope Stage 5e. The Eemian (also called the last interglacial, Sangamonian Stage, Ipswichian, Mikulin, Kaydaky, penultimate, Valdivia or Riss-Würm) 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. CO 2 concentrations over the last 400,000 years.
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