New Study: Modern Arctic Sea Ice Cover Is Present MONTHS Longer Than Nearly All Of The Last 8000 Years

A new reconstruction of Arctic (NW Greenland) sea ice cover (Caron et al., 2019) reveals modern day sea ice is present multiple months longer than almost any time in the last 8000 years…and today’s summer sea surface temperatures are among the coldest of the Holocene.

Yet another new study (Caron et al., 2019) shows today’s Arctic sea ice cover is still quite extensive when compared to the last several thousand years, when CO2 concentrations ranged between 260 and 270 ppm.

Image Source: Caron et al., 2019

Regional (northwest Greenland) sea surface temperatures were about 2°C warmer than at present for most of the last 6000 to 8000 years.

Image Source: Caron et al., 2019

Other new Arctic sea ice reconstructions from the north of Iceland (Harning et al., 2019) and Barents Sea (Berben et al., 2019) regions indicate a) modern sea ice extent has changed very little in the last several hundred years, or since the Little Ice Age, and b) the Early Holocene had millennial-scale periods of sea-ice-free and open water conditions, which is in stark contrast to “modern conditions” – the “highest value” or furthest extent of the sea ice record.

“[T]he PBIP25 values [proxy for sea ice presence] reach their highest value (0.87) of the record at ca. 0 cal yr BP. An increase in PBIP25 suggests a further extension in sea ice cover, reflecting Arctic Front conditions (Müller et al., 2011), most similar to modern conditions.” (Berben et al., 2019)

Image Source: Harning et al., 2019

Image Source: Berben et al., 2019