[Objective] The research aimed to analyze variation characteristics of the precipitation in Zigong City in recent 50 years.[Method] Based on daily precipitation data at three observation stations in Zigong City from 1...[Objective] The research aimed to analyze variation characteristics of the precipitation in Zigong City in recent 50 years.[Method] Based on daily precipitation data at three observation stations in Zigong City from 1961 to 2010,linear tendency method and accumulative anomaly method were adopted to analyze climatic change characteristics of the annual,seasonal,monthly rainfalls and rain days in Zigong City in recent 50 years.[Result]The annual rainfall overall presented a decreasing trend at the variation tendency rate of-28.0 mm /10 a in Zigong City.The annual rain days obviously declined at the variation tendency rate of-5.6 d /10 a.The decline of rain days was more obvious than that of the rainfall.Decline of the light rain days was especially serious.Not only trends of summer,autumn and winter rainfalls were all negative,but also trends of the four-season rain days were all negative.Reductions of autumn rainfall and rain days were the most remarkable and the largest in magnitude.Monthly rainfall presented single-peak type distribution,and monthly rain days presented double-peak type distribution.Days of each-level precipitation within one year in each area of Zigong City were nearly consistent.Moreover,rain days decreased as magnitude increased.An obvious characteristic of the precipitation variation in Zigong City in recent 50 years was synchronal decrease of the annual rainfall and rain days.[Conclusion]In general,the natural rainfall resource in Zigong City was tending to reduce,and autumn drought was obvious.展开更多
[Objective] The research aimed to study climatic characteristics of the thunderstorm days in Heze in recent 51 years. [Method] Using observation data of the thunderstorm days in Heze from 1961 to 2011, interannual and...[Objective] The research aimed to study climatic characteristics of the thunderstorm days in Heze in recent 51 years. [Method] Using observation data of the thunderstorm days in Heze from 1961 to 2011, interannual and monthly change characteristics of the thunderstorm days, change trends of the first and final dates, interannual stage distribution were analyzed. [Result] Annual average thunderstorm days in Heze was 25 d. As decade increase, thunderstorm days decreased at 1.9 d/10 a. Thunderstorm days concentrated from April to September, and occurred most often in July. The minimum days from first date to final date was 86 d, and the most days was 264 d. Average first date of the thunderstorm was on April 16, and final date was on September 16. Climatic characteristics of the thunderstorm had significant stage. [Conclusion] The research provided scientific basis for prediction, assessment, prevention and reduction of the thunderstorm disaster in Heze.展开更多
文摘[Objective] The research aimed to analyze variation characteristics of the precipitation in Zigong City in recent 50 years.[Method] Based on daily precipitation data at three observation stations in Zigong City from 1961 to 2010,linear tendency method and accumulative anomaly method were adopted to analyze climatic change characteristics of the annual,seasonal,monthly rainfalls and rain days in Zigong City in recent 50 years.[Result]The annual rainfall overall presented a decreasing trend at the variation tendency rate of-28.0 mm /10 a in Zigong City.The annual rain days obviously declined at the variation tendency rate of-5.6 d /10 a.The decline of rain days was more obvious than that of the rainfall.Decline of the light rain days was especially serious.Not only trends of summer,autumn and winter rainfalls were all negative,but also trends of the four-season rain days were all negative.Reductions of autumn rainfall and rain days were the most remarkable and the largest in magnitude.Monthly rainfall presented single-peak type distribution,and monthly rain days presented double-peak type distribution.Days of each-level precipitation within one year in each area of Zigong City were nearly consistent.Moreover,rain days decreased as magnitude increased.An obvious characteristic of the precipitation variation in Zigong City in recent 50 years was synchronal decrease of the annual rainfall and rain days.[Conclusion]In general,the natural rainfall resource in Zigong City was tending to reduce,and autumn drought was obvious.
文摘[Objective] The research aimed to study climatic characteristics of the thunderstorm days in Heze in recent 51 years. [Method] Using observation data of the thunderstorm days in Heze from 1961 to 2011, interannual and monthly change characteristics of the thunderstorm days, change trends of the first and final dates, interannual stage distribution were analyzed. [Result] Annual average thunderstorm days in Heze was 25 d. As decade increase, thunderstorm days decreased at 1.9 d/10 a. Thunderstorm days concentrated from April to September, and occurred most often in July. The minimum days from first date to final date was 86 d, and the most days was 264 d. Average first date of the thunderstorm was on April 16, and final date was on September 16. Climatic characteristics of the thunderstorm had significant stage. [Conclusion] The research provided scientific basis for prediction, assessment, prevention and reduction of the thunderstorm disaster in Heze.
