多模型综合的我国地表净辐射空间分布计算及时空变化

Spatial Distribution Calculation and Spatio-Temporal Variation of Surface Net Radiation in China by Using Multi-Model Synthesis Method

地表净辐射是地气系统的重要参数,在推动大气循环中发挥极大作用,准确估算其时空分布对于研究不同尺度气候变化及构建多种生态模型都具有重要意义。以2010年为例,通过精度分析得出1、2、3、4、5、8、9、11月回归法精度更高,误差绝对平均值约35.23MJ/m2,标准差约28.67MJ/m2,而6、7、10、12月彭曼修正式法推算值更接近辐射观测值,其误差绝对平均值约38.47MJ/m2,标准差约28.683MJ/m2。整体上回归法误差绝对平均值约36.36MJ/m2,标准差约28.67MJ/m2,精度优于彭曼修正式法。在上述思路的基础上,计算月尺度地表净辐射的空间分布,并对其时空变化进行了分析。结果表明:区域上,纬度是影响地表净辐射的重要因素,从低纬到高纬,地表净辐射逐渐减小,最大值出现在华南区,最小值出现在东北区;时间上,十年范畴内地表净辐射一直在波动,大体上呈逐年缓慢减小的趋势,在季节方面来说,地表净辐射呈现夏峰冬谷的状态,春季与秋季处于中间,而秋季略低于春季。

As an important parameters of geo-gas system,surface net radiation promotes atmospheric circulation,so the accurate estimation of the space-time distribution of surface net radiation is of great significance for the study of climate change at different scales and the construction of various ecological models.Taking 2010 as an example,the accuracy analysis results of this study show that the regression method is more accurate in January,February,March,April,May,August,September and November,with an absolute mean error of about 35.23 MJ/m2 and a standard deviation of about 28.67 MJ/m2.The calculated value of the Penman method in June,July,October and December is closer to the radiation observation value,with an absolute mean error of 38.47 MJ/m2 and a standard deviation of 28.683 MJ/m2.The absolute mean error of the regression method is 36.36 MJ/m2 and a standard deviation of 28.67 MJ/m2,which is more accurate than the Penman method.Based on the above methods,the paper calculated the space distribution of surface net radiation and analyzed its temporal and spatial changes.The results show that latitude is an important factor affecting the net surface radiation in terms of region.From low latitude to high latitude,the surface net radiation decreases gradually.The maximum value appears in Southern China,while the minimum in northeast.In terms of time,the surface net radiation has been fluctuating during ten years,and it is tending to slow down year-by-year as the whole.In terms of season,the maximum surface net radiation appears in the summer and the minimum in winter,and radiation in autumn is slightly lower than that in spring.