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is considered, then the desirability of further development of the Colo- rado River becomes economically questionable. " The weather and climate picture is very complicated. Some storms of a few hours duration can produce severe trouble. On the other hand, dry periods must be sustained for weeks or months, generally speaking, to be of drastic consequences. Sometimes a local drought region will turn up, with severe hardships for those living in it, even though no general regional drought is in progress. Sometimes a severe dry season, in a given region, will occur in the center of generally abundant rainfall. Often a drought pattern in one region will coincide with rain in another; sometimes there is no apparent connection at all between per- sistent anomalies in different parts of the earth at different times. Moreover, we have not yet solved even the fairly simple scien- tific proble ms of prediction of streamflow and underground water stor- age from known fluctuations of temperature and rainfall over a river basin. We do know, however, that river basins and underground storage layers are great integrators of short-term weather fluctua- tions. By the same token, however, systematic depletion of under- ground storage during sust ained years of drought can take years to rebuild, and can result in gross dislocations of the mineral content of the stored water, with resulting agricultural, human, and industrial complications. An interesting graph prepared by E. B. Kraus" of Australia shows the magnitude of the long-term abnormalities of rainfall that can occur at specific stations. (See graph attached as Appendix "B"). It is shown simply as an example, with no implication that such a trend is world-wide, though Kraus has suggested that such may be the case. This graph shows rainfall between May and October at Honolulu, Hawaii. It indicates that from about 1880 to 1902 the rain- fall in Honolulu (Hawaii) generally exceeded the average by about 250/0. Thus at the end of the 22 years the cumulated excess rainfall was five times the average amount of rain that falls in a single season. Then a reversal set in, with comparably sub-normal rainfall till about 1935. This wiped out the surplus, and piled up a cumulated deficit of almost twice a year I s rainfall. (b) Understanding the causes of the atmosphere's fluctuations. Droughts are produced by different causes in different parts of ""Secular changes of tropical rainfall regimes", Quarterly Journal of the Royal Meteorological Society, vol. 81, page 198, 1955. 5-