惠州市降水变化特征分析

Changing Characteristics of Precipitation in Huizhou

统计分析分析了1967-2006年惠州市降水的变化特征。结果表明:惠州市降水较多但年际变化较大,40年来全市年平均降雨量和雨日为1920.6 mm和148.5 d,北部山区降水明显多于中南部地区;降水的月和季节分布不均匀,易造成低温阴雨、洪涝、暴雨和干旱等灾害;年降雨量呈波动性变化无明显线性增减趋势,而年雨日除北部山区外中南部地区都呈显著减小趋势,近6 a与前33 a相比全市雨日平均减少了19.0 d,其中雨日的减少主要表现为小雨日的减少,今后降水时间分配趋向更不均匀,旱涝灾害更趋频繁。

Based on the daily rainfall data from 1967 to 2006 in Huizhou, the changing characteristics of precipitation and its effects on agriculture are analyzed. The results show that Huizhou has a higher precipitation with great seasonal variations, average annual rainfall and wet days are respectively 1920. 6mm and 148.5d in the recent 40 years. The precipitation is richer in North mountain areas than in middle south areas. The range of variation is more than 50%. The annual rainfall is fluctuant without obvious linear variations ; the annual wet days have an obvious decreasing in middle south areas, but not in north areas. In recent 6 years the annual wet days has a re- duction of 19. Od, compared with the past 33 years. The decreasing of light wet days is major, which means no continuous rainy days increase. Unevenly distributed precipitation in time would cause more drought and flood.