The objectives of the project are to better understand and quantify the following:

(1) How stratosphere affects the Earth surface climate and tropospheric large-scale circulation and cyclones?

(2) How large-scale circulation and cyclones affect the atmospheric moisture budget, clouds, precipitation, and the atmospheric boundary layer (ABL)?

(3) How clouds, precipitation, and ABL interact with sea ice?

The objectives address both the present-day climate and the projected climate in the end of 21st century. In the process understanding, the focus is on sea areas north of 70N, but the analyses of large-scale circulation and climate change will also address land areas in the region.

To meet Objective 1, we will carry out the following work

The work will be based on analysis of the CMIP5 future climate scenarios and sensitivity experiments applying ECHAM5 model with a full stratosphere and with a simplified one.

To meet Objective 2, we will analyse the following

The work will be based on several atmospheric reanalysis, satellite and rawinsonde sounding data, coastal cloud radar data, ship and aircraft expeditions in the central Arctic and, for future climate, CMIP5 products.

To meet Objective 3, we will carry out

The work will be based on ship, aircraft, cloud radar, and satellite data; reanalyses; new model experiments; and, for the future climate, CMIP5 products.

We expect that the most important result of CACSI will be a better understanding of the following: