Influence of atmospheric circulation on characteristics of convective and large-scale precipitation in Northern Eurasia

The contribution of dynamic and thermodynamic causes in changes of precipitation character in Northern Eurasia that is expressed in increase of convective and decrease of large-scale precipitation, is still undetermined. Here, we estimate influence of atmospheric circulation on various characteristics of convective and large-scale precipitation in Northern Eurasia using correlation and regression analyses. We estimate different measures for atmospheric circulation including frequency of cyclones and anticyclones, blocking duration, intensity of the main atmospheric centers of action. Correlation and regression analyses were carried out using nonparametric Mann-Kendall correlation and Theil-Sen estimator. We revealed local response of precipitation on circulation characteristics, which strength varies in space and time. For some regions and seasons, opposite responses for convective and large-scale precipitation were found. Therefore, changing character of precipitation over Northern Eurasia can partly be explained by dynamical factors. Nevertheless, the main reason for increase of convective and decrease of large-scale precipitation is presumably associated with thermodynamics factors, namely increase of surface air temperature and humidity that resulting in convective instability growth.