奉贤地区40年气候变化与农业合理开发利用

ANALYSIS OF CLIMATIC VARIATION IN FENGXIAN COUNTY [WT4HZ]DURING 40 YEARS(FROM 1959 TO 1999)AND ITS [WT4HZ]RATIONAL DEVELOPMENT AND UTILIZATION [WT4HZ]IN AGRICULTURE

根据奉贤 1959～ 1999年的降水、气温、日照资料 ,对奉贤 4 0多年的气候变化特征进行分析。结果表明 :4 0多年来奉贤地区年平均气温呈上升趋势 ,特别是进入 2 0世纪 90年代以来增温尤为显著 ,冬季变暖趋势 (为 +0 .4 8℃ /10年 )明显大于春、秋两季 ,夏季气温呈略下降趋势 ;年降水量呈上升趋势 (+6 5.7mm/10年 ) ,月际降水变化幅度加大。夏季降水量增多尤为明显(+91.7mm/10年 ) ,春季、冬季降水量呈波动状态 ,秋季降水量呈下降趋势 (- 38.1mm/10年 ) ;年日照时数依次分为上升期 (6 0年代中后期以前 ) ,下降期 (6 0年代末～ 80年代初 )和在平均值(194 4 .3h)上下振动期 (80年代中期以后 )三个阶段。此外 。

According to the data of precipitation,temperature and sunshine in Fengxian County from 1959 to 1999,the climatic variation in Fengxian was analyzed,the result is described as follows.During this period in Fengxian area,the annual average temperature has the tendency to raise especially since 1990s;the tendency to warm up in winter(0.48℃ increase/10 years)is obviously larger than that in spring and autumn,the temperature in summer has a small down trend.The annual precipitation tends to raise(65.7mm increase/10 years);the change range of monthly precipitation tends to extend;increase tendency of precipitation in summer is particularly evident(91.7mm increase/10 years);the precipitation is in a state of fluctuation in spring and winter and tends to decrease (38.1mm decrease/10 years)in autumn.The variation tendency of annual sunshine hours can be described by 3 phases,namely increasing phase(before mid and late 1960s) decreasing phase(from the end of 1960s to the beginning of 1980s)and the fluctuating phase(after mid 1980s)when the value of annual sunshine hours changes around the average value(1944.3h).In addition,the influences of climatic variation on agriculture and corresponding countermeasures are also preliminarily approached in the paper.