RAINFALL

In the absence of cooperative thermometers, the global warmers have been looking for other indicators - such as increased rainfall caused by increased evaporation of water caused by higher temperatures. World Climate Report 1, no. 3, p 1, available from P. O. Box 455, Ivy, VA 22945, reports that Vice President Gore, in his "Earth Day'' speech, said, "Torrential rains have increased in the summer during agricultural growing seasons.'' Figure 3 shows the data on which Gore based his remarks. Karl, T. R., Knight, R. W., and Plum-mer, N., Nature, 337, pp 217-220 (1995), found a 2% increase over the last 80 years in the amount of precipitation falling during rainstorms of two inches or more in 24 hours (as plotted in Figure 3). About 10% of the world's rain falls in these rainstorms. Described another way, there was one more such day of 2-inch rainfall on average in each 730 days.

Figure 4, however, provides further embarrassment for Gore's rain dance. It is one of five similar figures (the others show essentially the same result for different geographical regions) in "Evaporation Losing Its Strength'' by Peterson, T. C., Golubev, V. S. and Groisman, P. Y., Nature 377, pp 687-688 (1995). Reported are data from 936 evaporation-pan stations where rate of water evaporation is measured. Evaporation rate is, of course, dependent upon many factors besides temperature, but the "torrential rains'' are supposed to have resulted from increased evaporation. As the figure shows, evaporation rates have actually fluctuated downward during the period in question.