Arctic sea ice changes – from quiet to more dynamical regime

Speaker:

• Jari Haapala, Finnish Meteorological Institute

Mass balance of the Arctic Sea ice depends on thermodynamical and dynamical factors. Thermodynamical and mechanical sea ice state variables are strongly coupled, but the strength of coupling varies in daily, seasonal and climate time scales. When the ice pack is thick, solid and compact, this coupling is strong and large areas of the ice pack are mechanically connected. In these circumstances, internal stress of pack ice is accumulating and reducing differences in ice motion.

In these conditions drift speed of Arctic Sea decreases, age of ice increases and total mass of ice pack increases. On a contrary, thinner ice pack which includes cracks, leads or larger open water areas is in turn mechanically weakly connected, exhibits larger variations in motions in shorter time and length scales, drifts with higher speed and exhibits shorter residence time in theArctic. In this talk, the importance of ice dynamics on sea ice mass balance is reviewed and new findings based the MOSAiC campaign are discussed.

About the S.T. Lee Young Scientist Exchange: The S.T. Lee Young Scientist Exchange is a partnership between IARC and the Antarctic Research Centre, Victoria University of Wellington. The program supports exchange of students and early career scientists between the two institutions to promote the sharing of knowledge and ideas between Arctic and Antarctic focused research. The S.T. Lee Lecture was established by Singaporean philanthropist Lee Seng Tee. IARC also participates in the S.T. Lee Fellowship program, which supports lectures by senior-level researchers.