中国西北地区太阳辐射时空分异特征

Anomaly temporal-spatial distribution of solar radiation in Northwest China

应用近60 a中国西北169个国家基本气象站气象观测资料,对中国西北总辐射的时域变化、空间分布和次区域时空演变特征进行了研究。结果表明:(1)青海西北部的柴达木盆地和甘肃西部为太阳能资源最丰富区,陕西南部和甘肃东南部的较小区域为资源丰富区,其余大面积区域均为资源很丰富区。(2)1961—2020年除新疆西南部、甘肃和新疆接壤区、甘肃北部和陕西北部的小范围区域总辐射呈上升趋势外,西北大部分区域总辐射呈下降趋势。(3)EOF第一模态特征向量场表明,总辐射振荡强度由西向东加强,各分量高载荷区主要集中于中东部,该区域是总辐射易出现异常、振荡强且敏感的地区。(4)EOF第二模态特征向量场自西向东呈双偶极子型;青海全境和甘肃大部为正值区域,也是总辐射异常振荡最强的区域。(5)依据REOF特征向量不同模态空间分异结构类型,可将研究区域划分为主要受东亚季风影响的“西北东部异常型”、主要受东亚季风影响边缘区的“西北中部异常型”和主要受西风带影响的“西北西部异常型”等3个次区域。3个次区域总辐射减少的突变点分别出现在1973年、2017年和2008年。

The temporal variation,spatial distribution,and temporal and spatial evolution characteristics of the total radiation in Northwest China were studied using meteorological observation data from 169 national meteorological stations in Northwest China,over the past 60 years.The Qaidam Basin in the Northwest of Qinghai and the west of Gansu were the most abundant areas for solar energy resources,the smaller areas in the south of Shaanxi and the southeast of Gansu were found to be resource rich areas,and the other large areas are resource rich areas.From 1961 to 2020,the total radiation showed an upward trend in Southwest Xinjiang,the border area between Gansu and Xinjiang,and smaller areas in northern Gansu and northern Shaanxi,while the total radiation showed a downward trend in most regions of Northwest China.The eigenvector field of EOF mode 1 shows that the total radiation oscillation intensifies from west to east,and the high load area for each component is mainly concentrated in the middle and east,which is the region where the total radiation is prone to be abnormal and the oscillation is strong and sensitive.The eigenvector field of the second EOF mode presents a dipole type from west to east.Qinghai and most of the Gansu are positive regions,which are also the regions with the strongest total radiation and abnormal oscillation.According to the different modal spatial differentiation structure types for the REOF eigenvectors,the study area can be divided into three sub regions,namely:“Eastern northwest anomaly type”which is affected by the East Asian monsoon;“Central northwest anomaly type”which is the marginal region and mainly affected by the East Asian monsoon;and“Western Northwest anomaly type”which is mainly affected by the westerlies.The mutation points for total radiation reduction in the three subregions occurred in 1973,2017,and 2008 respectively.