On nature and structure of atmospheric circulation anomalies in opposite seasons

In this paper, we consider circulation anomalies obtained in the model of atmospheric general circulation when incoming short wave radiation changes and the initial state anomalies are given. We also consider circulation differences during the years of high and low moisture content in the atmosphere, using the reanalysis data.

Using the global model, we studied such winter and summer circulation anomalies that result from the attenuation of winter radiation forcing and accordingly reduction in summer radiation atmosphere heating. In the other series of experiments the joint 'atmosphere-soil' initial moisture anomalies in transitional seasons (autumn, spring) are formed by using a hemisphere model and their effects on the subsequent structure of the circulation anomalies are investigated.

It turned out that these anomalous numerical experiments different both in the boundary and initial conditions model the similar anomalies. Namely, in transition in the annual variation to winter circulation (or in winter) pressure long-wave troughs and ridges are damped, in transition to summer circulation (or in summer) west-east transport at the high latitudes is attenuated by the modelled anomalies.