ABSTRACT
The serious study of climatic impact on human society was a phenomenon of the 1970s—as it was in the 1930s. In those two decades climate upset the economic apple-cart severely enough to be noticed on the world scale. The losses of soil and distress of the dirt farmer were both a prime target of New Deal measures, and a highly visible testimony to the power of climate to disrupt human affairs. The World, US and Canadian climate programs aim to achieve the improvement. The elasticity of world trade is such that small variations of supply of the magnitude could and did produce doublings and triplings of the world price of wheat and rice. In any case, climatic anomalies tend to cancel one another when they are averaged over sufficient space. Drought in one large continental area will generally be counterbalanced by good growing conditions in another.
