Session 03 - Short Summary

This session summarizes the current state of knowledge regarding past observed trends in Arctic climate variables and their projection by climate models. Topics include studies on near-surface warming trends in the Arctic and their drivers; changes of sea ice (extent, thickness, volume) and melt ponds; trends in Arctic cyclones (frequency, intensity, and regional patterns) and circulation regimes; changes of oceanic heat transport; atmospheric moisture and clouds; aerosol particles and trace gases; and other parameters of the Arctic system. Contributions comparing observed and modeled trends, as well as those contrasting trends in the Arctic and Antarctic, are also welcome.