10,000 years of melt history of the 2015 Renland ice core, EastGreenland

• Main Authors: Taranczewski, Tetsuro, Freitag, Johannes, Eisen, Olaf, Vinther, Bo, Wahl, Sonja, Kipfstuhl, Sepp
• Format: Text
• Language: English
• Published: 2019
• Subjects: Greenland; Renland; East Greenland; Ice cap; ice core; Ice Sheet
• Online Access: https://doi.org/10.5194/tc-2018-280; https://tc.copernicus.org/preprints/tc-2018-280/

An ice core drilled in 2015 on the Renland ice cap at the eastern margin of Greenland has been inspected with regard to its melt content. The thickness of a melt layer reflects the temperature level at the time of melt generation. Hence the melt layers are an indicator of past regional summer temperatures in East Greenland, a region where paleoclimate records are sparse. Melt layers have been identified almost along the whole core, resulting in a melt record reaching back 10,000 years. By gathering additional information about melt rates as well as high-resolution densities in two shallow cores, we developed an approach to correct the annual melt content for the ice volume that gets lost by the thinning process. The result is a melt record with decadal- to centennial- scale resolution for the last two millennia, and the most accurate Holocene climate record for Eastern Greenland so far. The observed changes of annual melt rates show a warm early Holocene, with melt rates higher than in the recent past century, and minimum melting during the Little Ice Age. Current melt rates show a strong increase for the early 20th century as well as for the time since the end of the past century, with the recent 2012 extreme melting of the Greenland Ice Sheet being the strongest melt event in the past 500 years.