The linkage between Arctic sea ice changes and mid-latitude atmospheric circulation in reanalysis data and model simulations— The role of barotropic-baroclinic interactions

bserved global warming trends have their maximum in Arctic regions, a phenomenon referred to as Arctic Amplification. Consequently, Arctic sea ice shows a strong decreasing trend. These changes imprint modifications on atmospheric flow patterns not only in Arctic regions themselves. Changes of teleconnections and planetary scale motions like Rossby wave trains affect mid-latitude climate as well. In extension to the studies by Jaiser et al. (abstract submitted) here we study the impact of sea-ice changes on changes in atmospheric synoptic and planetary waves. Therefore, we analyse the atmospheric kinetic energy spectra for ERA-Interim reanalysis and the properly designed Atmospheric General Circulation Model (AGCM) experiments with prescribed sea-ice changes (cf. abstract by Jaiser et al.). Special emphasis has been put on the the role of barotropic-baroclinic interactions and corresponding changes in the tropospheric planetary wave trains by examining the nonlinear kinetic energy and enstrophy interaction and subsequent redistribution of kinetic energy and enstrophy.