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Secular Changes Of Precipitation In The Rocky Mountain States, Raymond S. Bradley

Raymond S Bradley

Long-term preCIpitation records from Montana, Idaho, Wyoming, Utah and western Colorado were obtained and carefully screened for missing data and station relocations. Each record was divided into five seasonal series and tested for homogeneity. Most of theunhomogeneous records were for the winter season, whereas there were fewest for summer and late summer seasons. Those seasonal records considered to be homogeneous were then used to examine the spatial variation of precipitation anomalies decade by decade (1891-1900, 1901-1910, etc.) from 1941-70 averages. Areas of statistically significant anomalies were identified. Generally, precipitation was high in the 1890's, 1910's and/or 1920's, 1940's and 1960's. …