近50a葫芦河流域气候变化特征

Characteristics of climate changes in Hulu River basin since recent 50 years

根据静宁、秦安两站的水文气象资料,分析了葫芦河流域近50 a气候变化特征.采用Mann-Kendall法分析,结果显示近50 a气温总体呈上升趋势,降水量呈下降走向.利用Meyer小波及Morlet小波分别分析并相互检验校正葫芦河流域年均气温及年降水量的主要变化周期,其中:年平均气温普遍存在30 a以上,22,12～14,10 a左右的中长周期以及4～7,2～3 a的短周期,而年降水量存在30 a以上,20,12～14,10 a左右的中长周期以及6～8,2～4 a的短周期.近50 a葫芦河流域河川径流的变化主要受当地降水波动的影响.

Based on the data of air temperature and precipitation from the meteorological stations in Jingning and Qin＇an, the Mann-Kendall method is applied to the tendency characteristics of climate changes of the recent 50 years in Hulu River basin, which show that the general variance of annual mean air temperature is increasing and annual total precipitation is declining. The results of the Meyer and Morlet wavelet analysis show that there are multi-scaled period changes for annual air temperature and precipitation, i.e. mid-long periods of 30, 22, 12-14, 10, and short periods of 4-7, 2-3 for air temperature; mid-long periods of 30, 20, 12-14 and 10 and short periods of 6-8 and 2-4 annual precipitation.