1960-2013年宝鸡市降水变化特征分析

为正确认识宝鸡市降水变化特征,以1960-2013年宝鸡各气象站点逐日降水量实测值为基础,综合运用气候倾向率、累积距平法、Morlet小波函数以及R/S分析法对研究区降水量的时间变化特征进行诊断分析。研究结果表明:近54 a宝鸡市平均降水量总体呈减少趋势,夏、冬两季降水量增加,春、秋两季降水量减少。降水量呈现大小尺度相互嵌套的周期变化趋势,年降水特征时间尺度为32、12、6以及4 a,季节降水存在4~7、10~17以及24~32 a的变化周期。未来宝鸡降水变化趋势与过去变化趋势相一致,年以及春、秋两季降水仍将呈现减少态势,夏、冬两季降水则继续呈增加态势。此外,影响夏季降水系统发展变化的因素最为复杂。

Analysis of precipitation variation characteristics in Baoji from 1960 to 2013

In order to reveal the variation characteristics of precipitation in baoji,the paper took. the meteorological observation data as the base in Baoji from 1960 to 2013,and analyzed the temporal variation characteristics of precipitation by using the general linear regression analysis, Morlet wavelet analysis and R/S analysis. The results showed that the precipitation has a general decreasing tendency for 54 years.Precipitation increases in summer and winter, and reduces in spring and autumn. Precipitation shows periodic change trend of different dimensions.The annual temporal scales of precipitation feature are 32,12,6 and 4 years. The seasonal temporal scales of precipitation feature are 4 to 7,10 to 17 and 24 to 32 years.The future variation trend of precipitation will keep consistent with that in the past.The precipitation in annual, spring and autumn will present the trend of decrease,and that in summer and winter will continue to increase.The factors that affect the change of precipitation in summer is the most complicated.