桓仁县气候极值特征分析

Extreme Climate Feature Analysis of Huanren County

根据桓仁县1953～2002年的气温和降水资料,分析了历年气温、降水极值变化规律。结果表明:20世纪80年代中期之前桓仁县历年极端最高气温波动较小,1986年以后波动增大,总体呈偏高;历年极端最低气温以1972年为转折点,呈明显的非对称性,1973～2000年总体明显偏高,极端最低气温的递增对气候变暖贡献最大;历年一次最大降水量极值曲线呈渐少走向,降水量极值减弱还表现为≥200mm过程的减少,而≤100mm过程的增多;历年最长无降水日数变化不大,但30～35d以上无降水日数则逐年增多,表明干旱趋于严重化。

According to the temperature and precipitation materials for 1953-2002 in Huanren,the changing rules for the extreme data of temperature and precipitation（including the most extremely high temperature,the most minimum temperature,one of the largest continuous precipitation,no number of days of continuous precipitation）over the years were analyzed.The results showed that the most extremely high temperature over the years fluctuated relatively lightly before the middle period of the eighties in Huanren,and it fluctuated heavily after 1986.Totally it was presented a bit high.The most extremely minimum temperature over the years regarded 1972 as turning point,and it was presented prominent asymmetry.Overall it was obviously on the high side in 1973-2000.The increase of the most extremely minimum temperature was the mainly reason why the climate became warm.The curve for one of the largest continuous precipitation was presented fewer gradually.The extreme value of precipitation was weakened gradually,shown as the reduction for the course of ≥200mm and the increasing for the course of≤100 mm.Days of no continuous precipitation didn＇t changed obviously,but the above number of days increased year by year in 30-35 days.It indicated that the situation of aridity was tending to be more serious.