Abstract:
In view of the frequent occurrence of regional precipitation anomalies in recent years, we analyzed the spatial-temporal variation characteristics of precipitation pattern in Guizhou Province based on the daily precipitation data from 32 meteorological stations in 57 years (1960~2017) in Guizhou Province. In this paper, the incidence rate and contribution rate of precipitation events were used to assess the precipitation variations. The Mann-Kendall test was adopted to investigate the trends of precipitation change. The results showed that:① With the increase of precipitation duration, the incidence rate of precipitation events displayed a decreasing trend, and the contribution rate of precipitation events increased first then decreased. The contribution rates of 2~4 d duration precipitation events were high in Tongzi, Zhengan, Renhuai, Yuqing, Sinan, Tongren, Guiyang, Luodian and Rongjiang meteorological stations. The contribution rates of >10d duration precipitation events were high in Weining, Pu 'an, Panxian, Zhijin, Xingren and Xingyi meteorological stations.② With the increase of precipitation grades, the incidence rate of precipitation events displayed a decreasing trend, and the contribution rate of precipitation events increased first then decreased. The contribution rates of precipitation events were high in Wangmo, Zhijin, Duyun and Anshun meteorological stations.③ In terms of precipitation duration, the varying trends were similar for incidence rate and contribution rate. The upward trend was detected in the short-duration precipitation events, while the downward trend was detected in other duration precipitation. In terms of precipitation grades, the changing trends were similar for the incidence rate and the contribution rate. Heavy and storm rain events showed an increasing trend, and a decreasing trend was found in light rain events. However, an increasing trend was found in the incidence rate of moderate rain events, the opposite trend was found in the contribution rate of moderate rain events. The results could provide a scientific basis for the disaster prevention and mitigation in Guizhou Province.