- Aug 11, 2021
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Actually, it was much warmer in the Eemiam than now.
At 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 hippopotamus was distributed as far north as the rivers Rhine and Thames. 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. 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 the Great Plains of the United States lay further west near Lubbock, Texas, whereas the current boundary is near Dallas.
And even at Holocene climate optimum there was a bit warmer that now.
The Holocene Climate Optimum warm event consisted of increases of up to 4 °C near the North Pole (in one study, winter warming of 3 to 9 °C and summer of 2 to 6 °C in northern central Siberia). Northwestern Europe experienced warming, but there was cooling in Southern Europe. The average temperature change appears to have declined rapidly with latitude and so essentially no change in mean temperature is reported at low and middle latitudes. Tropical reefs tend to show temperature increases of less than 1 °C. The tropical ocean surface at the Great Barrier Reef about 5350 years ago was 1 °C warmer and enriched in 18O by 0.5 per mil relative to modern seawater. In terms of the global average, temperatures were probably warmer than now, depending on estimates of latitude dependence and seasonality in response patterns. Temperatures in the Northern Hemisphere were warmer than average during the summers, but the tropics and parts of the Southern Hemisphere were colder than average.
Of 140 sites across the western Arctic, there is clear evidence for conditions that were warmer than now at 120 sites. At 16 sites for which quantitative estimates have been obtained, local temperatures were on average 1.6±0.8 °C higher during the optimum than now. Northwestern North America reached peak warmth first, from 11,000 to 9,000 years ago, but the Laurentide Ice Sheet still chilled eastern Canada. Northeastern North America experienced peak warming 4,000 years later. Along the Arctic Coastal Plain in Alaska, there are indications of summer temperatures 2–3 °C warmer than now. Research indicates that the Arctic had less sea ice than now.
Current desert regions of Central Asia were extensively forested because of higher rainfall, and the warm temperate forest belts in China and Japan were extended northwards.
West African sediments additionally record the African humid period, an interval between 16,000 and 6,000 years ago during which Africa was much wetter than now. That was caused by a strengthening of the African monsoon by changes in summer radiation, which resulted from long-term variations in the Earth's orbit around the Sun. The "Green Sahara" was dotted with numerous lakes, containing typical African lake crocodile and hippopotamus fauna.
I never said that the earth wasn't warmer in the past. So all of what you wrote was for nothing.