The Eemian Interglacial
Posted on: December 21, 2018
SUMMARY: The Eemian interglacial started 130,000 years ago and ended about 115,000 years ago when the Last Glacial Period got started. Despite the usual claim that the intensity of “post industrial anthropogenic global warming” is unprecedented, it is generally agreed that the Eemian, at times, was warmer than the the present by as much as 5ºC. In general, the Eemian is described as hotter than today with January temperatures 3ºC to 5ºC higher and July temperatures 2ºC to 4ºC higher but with large fluctuations in temperature between conditions hotter than today and colder than today. The Eemian is characterized by rapid fluctuations between warm and cold periods in multi-decadal time scales. Fluctuations in winter temperatures correlate with rise and fall of sea level. The changes are described as abrupt climate change over decades with great regional variability but with rapid recovery from these changes. It is generally agreed that Eemian climate was more unstable than the Holocene with multiple cold periods lasting from decades to centuries. A remarkable shift occurred about 5,000 years into the Eemian when it cooled by 6ºC to 10ºC before rising again to warm conditions.
A significant feature of the Eemian is sea level rise and fluctuations in sea level caused by fluctuations in temperature. Sea level rise of 3 to 6 meters are reported by some authors and 5 to 9 meters by others and is generally attributed to a complete disintegration of the West Antarctic Ice Sheet and it was likely the main source of the dramatic sea level rise found in the data. Some authors cite sudden warming of 5ºC to 10ºC and “massive surges of icebergs into the North Atlantic” as a perturbation of ocean circulation that was responsible for abrupt climate change in the Eemian. Details of these findings may be found in the Eemian Bibliography presented below.
CONCLUSION: We propose in this post that the fear of ice sheet collapse and devastating sea level rise in the current warming episode described by James Hansen and by other climate scientists can be related to events in the Eemian but not to the post LIA period of the Holocene.
FIGURE 1: JAMES HANSEN ON EEMIAN SEA LEVEL RISE
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