Warm Nordic Seas delayed glacial inception in Scandinavia
1Bjerknes Centre for Climate Research, Bergen, Norway
2Geophysical Institute, University of Bergen, Bergen, Norway
3Laboratoire des Sciences du Climat et l'Environnement, Gif sur Yvette, France
4UNI Research, Bergen, Norway
*now at: Climate and Environmental Physics, Physics Institute, University of Bern, Bern, Switzerland
Abstract. We simulate the last glacial inception, 115 000 years ago, with a three dimensional thermomechanical ice sheet model of the Northern Hemisphere, forced by a comprehensive coupled climate model. High oceanic heat transport into the Nordic Seas prevents large scale ice growth over Scandinavia. Glacial inception in the region starts on the highest mountains in the south when sea surface temperatures in the Nordic Seas are reduced by at least 3 °C. Ice growth in Northern Scandinavia requires a cooling by at least 4 °C. This is in good agreement with marine proxy data from the Nordic Seas and North Atlantic as well as available terrestrial data. This study thus provides a physical understanding and revised timing of the first glacier advance over Scandinavia.