Secular Variation Tendency of Precipitation and Droughts in South of Shandong
Based on the monthly precipitation date from 2 stations in the South of Shandong Province, the se cular variation tendency of precipitation and the drought frequency are analyzed with the accumulated anomalous, skids the ttest and KruskalWallis assay metho d. The results show that there is a evident decrease of the precipitation in the south of Shandong Province since 1950s, and a sudden change spot in the mid 197 0s. After the chang spot, the precipitation reduced above 12%, especially in the rainy season, the precipitation reduced remarkably, above 16%. The dry season p recipitation change was not remarkable. The droughts all happened after the sudden change spot. The dry season frequency and their intensities obviously increas e since the sudden change spot. The frequencies of the 3 dry month are high and the periods of continuous droughts are obviously long.