by R. Hannon/A. May, May 27, 2020 in WUWT
Introduction
The Arctic and Antarctic regions are different and yet similar in many ways. The Arctic has ocean surrounded by land and the Antarctic is a continent surrounded by water. Both are cold, glaciated and located at Earth’s poles some 11,000 miles apart. While sea ice has been retreating in the Arctic, it has been relatively stable in the Antarctic. This post examines surface temperature trends, solar insolation, and CO2 at the polar Arctic and Antarctic regions during the Holocene interglacial period.
Holocene Polar Temperature Trends are Out of Phase
The Holocene interglacial started about 11,000 years ago after termination of the previous glacial period. It is commonly described as consisting of an early Holocene climate optimum from approximately 10,000 to 6,000 years before present (BP, before 1950). This optimum is followed by a pronounced cooling in the mid-late Holocene referred to as the Neoglacial period which culminates in the Little Ice Age (LIA) around 1800 years AD (Lui, 2014).
Past Holocene temperature anomalies are typically estimated from ice core proxies. This post uses Arctic temperature anomalies from Agassiz-Renland isotope data corrected for elevation by Vinther, 2009 and Antarctic temperature anomalies from Dome C ice core proxies calculated by Jouzel, 2001. Temperatures are presented as anomalies relative to present day average polar temperatures. Time is shown as both years AD/BC and years before present, BP. Years BP (yr BP) is the key reference in the text. Datasets used are referenced at the end of the post.
Arctic and Antarctic Holocene temperature anomalies are shown in Figure 1. Arctic temperature anomalies show a prominent climate optimum from 10,000 to 6,000 yr BP with a brief cold interruption around 8,200 yr BP. The Neoglacial cooling is also evident where Arctic temperature anomalies steadily cool from 6,000 yr BP to the LIA as described in the literature.
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