Arizona State University

Step 1: Look at the top of the graph for when glacial maxima times occurred (the down arrows). Maxima occurred when the sun’s noontime insolation (radiation) was at is maximum in winter at the latitude where moisture would be evaporated (20˚N) for snowstorms, and was at its minimum in summer (37˚N) so as to not melt the glaciers. ................
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