Evelien Dekker, PhD student, MISU


The impact of a warm moist air intrusion on dynamic and thermodynamic sea ice tendencies in the Arctic.


Atmospheric blocking events in the Northern Hemisphere have been related to regional Arctic sea ice decline. During blocking events, pulses of warm and moist air enhance the radiative forcing on the sea ice in winter due to the increased longwave radiation associated with clouds. Several studies have shown that such events are related to regional sea ice concentration decline.

Daily sea ice output with the latest version of CICE from the coupled Regional Arctic System model is used to study sea ice tendencies during January-February 2014. In this period there was a follow-up of a Atlantic warm moist air intrusion and a Pacific warm moist air intrusion associated with surface air temperature perturbations up to 20 degrees locally.

A decline in sea ice concentration during wintertime does not necessarily mean that ice melt occurs. The goal of this case study is to distinguish the sea ice response between a dynamic and a thermodynamic component. In this way, we learn how much of the sea ice is advected into another region during such an event and how much the sea ice is lost due to growth stagnation during the period of the enhanced forcing and temperature increase.


Thursday February 20, 14:15


Rossbysalen C609, Arrhenius laboratory, Svante Arrhenius väg 16C, 6th floor