It is mid-thirties, and the United States is in the middle of the Great Depression and the Dust Bowl. The drought that has struck Texas and Oklahoma is wreaking havoc in the American prairies. Lacking the strong root system of grass, the winds easily pick the loose topsoil and swirl it into dense dust clouds, known as the black blizzards. The dust chokes thousands of cattle and drives 60 percent of the population, later they called them exodusters, first in the cities, and later in the agricultural regions in the Far West.
At the same time at the University of Wisconsin, the geographer Glen Thomas Trewartha keeps himself busy investigating the weather and the climate elements, such as temperature, precipitation, and storms and their relative significance in contributing to an understanding of regional climates.