Fig. 4: Major pathways for seasonal snow to impact atmospheric circulation and weather/climate variability.

A stronger Siberian High is usually observed in response to an increase in autumn snow cover, which is accompanied by anomalous vertical wave activity to the stratosphere, (upward thick red wavy arrows) causing polar vortex disruptions, for example by inducing stretching of the stratospheric polar vortex. The land-sea thermal contrast is usually enhanced by earlier snowmelt or less snowmelt, causing, for example, stronger Asian monsoon flow. The land-surface pathway involves snowmelt in spring/early summer, which affects surface albedo, surface runoff and soil moisture, and induces subsequent soil moisture–atmosphere interactions. This effect strongly depends on soil moisture memory, which is still an active topic of research.