Name:   MAJ USA RET - Subject:   "correct temperature" is a moving target Date:   7/17/2019 4:39:24 PM (updated 7/17/2019 4:40:26 PM)

Climatologist Cliff Harris and Meteorologist Randy Mann… in an article and chart updated, March 10, 2018… set the mean global temperature, at 57.0^oF (13.9⁰C)… over the last 4,500 years.

“Approximately 56 million years ago, our planet was in the Paleocene-Eocene Thermal Maximum as global mean temperatures were estimated as high as 73 degrees Fahrenheit, over 15 degrees above current levels. Ocean sediments and fossils indicate that massive amounts of carbon dioxide were released into the atmosphere.” (ibid)    73^oF = 22.8⁰C.

The current interglacial period is about 10K years old and the maximum temperature was 57.6^oF (14.2⁰C) 8K years ago.  Global temperature has been, on average, dropping since then. 

If this interglacial behaves as have all of the previous ones, we are approaching the downturn into the next ice age.  The Sangamon interglacial lasted approximately 11K years before dropping into the Wisconsin glacial period which lasted approx 83K years. The Younger Dryas (over a period of approximately 3K years) was the warming period... at the end of the Wisconsin... immediately prior to our current interglacial.