Abstract:

In order to make a comprehensive analysis on the temporal distribution regularity and variation trend, providing scientific basis for water resource prediction, prevention and mitigation of flood & drought disaster, water regulation, as well as water resource management, the annual precipitation grade of Baoji were analyzed by using weighted Markov chain. Considering the uncertainty and imprecision of precipitation process, the precipitation numbers of Baoji from 1956 to 2009 were classified into 5 grades: drought, partial drought, normal, partial abundance and abundance, by using mean-standard deviation classification method. Regarding standardized self-coefficients as weights, the precipitation grades of the future years in Baoji were predicted by using weighted Markov chain. Analysis on stationary distribution showed that, the probabilities of 5 grades above were respectively 0.1305, 0.2767, 0.2751, 0.2075, 0.1101. The partial drought and normal grades dominated in the long-term precipitation process, reflecting warming-drying trend of climate changing in Baoji.