阿里地区狮泉河近30年总辐射和净辐射的变化特征

基于阿里地区狮泉河地气交换综合观测站2019年辐射观测数据和狮泉河气象站1993~2016年辐射观测数据，分析了阿里地区总辐射和净辐射的日循环、日变化、季节变化和年际变化特征。结果表明:（1）阿里地区总辐射和净辐射平均日变化峰值出现在14:30~15:00，总辐射月均值最大值出现在6月，净辐射月均值最大值出现在8月，近20 a来阿里地区总辐射和净辐射的平均日变化峰值和月均值最大值出现时间延后。（2）1993~2016年阿里地区总辐射曝辐量呈微弱的减少趋势，但其日最大辐照度呈极显著降低趋势，而净辐射曝辐量呈极显著增加趋势，但其日最大辐照度呈现微弱的减少趋势。（3）1993~2016年阿里地区总辐射和净辐射日最大值出现时间年均值均呈极显著的延后趋势，年均净辐射日最大值出现时间较总辐射日最大辐照度出现时间平均提前约13 min。 

Variation Characteristics of Total Radiation and Net Radiation in Ali Area in Recent 30 Years

Based on the observation data of Shiquanhe Earth-atmosphere Exchange Comprehensive Observation Station in Ali area in 2019 and the radiation observation data of the Shiquanhe Meteorological Station from 1993 to 2016, the diurnal cycle, diurnal variation, seasonal variation and interannual variation characteristics of total radiation and net radiation in Ali area are analyzed. The results show that: (1) The average daily variation peak of total radiation and net radiation in Ali area appeared at 14: 30 ~ 15: 00, the maximum monthly mean of total radiation appeared in June, and the maximum monthly mean of net radiation appeared in August. In the past 20 years, the average daily variation peak and monthly mean maximum of total radiation and net radiation in Ali area were delayed. (2) From 1993 to 2016, the exposed radiation of total radiation in Ali area showed a weak decreasing trend, but its daily maximum irradiance showed a very significant decreasing trend. The exposed radiation of net radiation showed a very significant increasing trend, but its daily maximum irradiance showed a weak decreasing trend. (3) From 1993 to 2016, the occurrence time of the daily maximum value of total radiation and net radiation in Ali area showed a very significant delay trend, and the occurrence time of the daily maximum value of average annual net radiation was about 13 minutes earlier than that of the daily maximum irradiance of total radiation.