Hurd C. Willett

THE PATTERN OF SOLAR CLIMATIC RELATIONSHIPS

Evidence as to the tentative pattern of atmospheric reaction to sudden solar disturbance of the corpuscular (charged particle) and of the ultraviolet types is briefly reviewed in this paper. Similarity of the reactions of the mean patterns of the general circulation a t alternate sunspot maxima to these two sudden reaction patterns is noted, and the principal corresponding climatic effects are briefly noted. A similar comparison is made of the climatic responses to the 80to 90-year sunspot cycle, notably as regards the northern hemisphere pattern of the warming trend from 1900 to 1940, which is analyzed in some detail for the winter and for the summer season separately.

Solar Prediction of Climatic Change

In their broad synoptic features the basic hemispheric patterns of climate, on which the patterns of climatic change depend, fall into two distinctive categories, the zonal and meridional. Distinctive synoptic features of the primary zonal patterns are first described. Then statistically significant relationships are examined between the temporal changes in these patterns and the long secular cycles of sunspot and related variable solar activity. It is these relationships that lend them selves to the statistical prediction of long-term climatic trends. Possible physical linkage between disturbing solar impulses and atmospheric response is suggested. A significant relationship between zonal climatic patterns and shorter term (22 years) double sunspot cycles is noted. Distinctive syn optic features of the primary meridional patterns of climate and climatic change are then described. They are of short duration and relate significantly only to double sunspot (DSS) and shorter cycles, notably at higher latitud...