基于开源GIS的长江流域晴日辐射反演  

RETRIEVAL OF CLEAR-SKY RADIATION IN THE YANGTZE RIVER BASIN BASED ON OPEN-SOURCE GIS

作　　者：张玉龙[1,2] 夏小玲[1] 陈正洪 党海山[1] 张全发[1] 

机构地区：[1]中国科学院武汉植物园水生植物与流域生态学重点实验室,湖北武汉430074 [2]中国科学院研究生院,北京100049 [3]湖北省气象能源技术开发中心,湖北武汉430074

出　　处：《长江流域资源与环境》2011年第9期1073-1079,共7页Resources and Environment in the Yangtze Basin

基　　金：国家自然科学基金项目(30900199);中国气象局气候变化专项(CCSF-10-04);科技部公益性行业科研专项(GYHY201006036)

摘　　要：以开源GIS软件GRASS为平台,首次通过辐射过程模型r.sun和编程语言Shell实现长江流域500 m分辨率的晴日辐射反演(包括直接辐射、散射辐射和反射辐射),为了解长江流域辐射时空分布规律和相关宏观气候、生态建模奠定基础。结论如下:(1)精度验证表明,晴日辐射反演结果较理想;相关晴日指数的误差指标MPE、MAPE和RMSE分别为3.7%、7.5%和6.4%,r.sun模型可进一步用于中国其它区域;(2)长江流域晴日辐射年均日值为24.24±2.45 MJ/(m2.d),其各组分差异显著,直接、散射、反射辐射分别占总辐射的84.2%、15.6%和0.2%;(3)晴日辐射空间分布梯度明显,沿三级地形阶梯向东辐射值及变异逐渐减小,海拔变化引起的大气衰减因素在决定晴日辐射分布时起重要作用;(4)晴日辐射季节分布不对称,月际变化总体呈倒"U"形分布;直接辐射和散射辐射变化趋势基本一致,但二者比例随大气浑浊度的变化波动剧烈。Based on the platform of open-source geographic information system GRASS,500 m resolution datasets of clear-sky radiation（including beam,diffuse and reflected radiation） in the Yangtze River Basin were firstly calculated with process-model r.sun and programming language Shell,which can help to understand spatio-temporal pattern of energy over the basin,and provide data for macro-climatic and ecological modeling.The results are as follows：（1） Validations show that r.sun model on the retrieval of the clear-sky radiation of the Yangtze River Basin performs relatively well,with the MPE（3.7%）,MAPE（7.5%） and RMSE（6.4%） of related clear-sky index.The model can be further used in other regions of China.（2） Annual mean radiation,with an average value 24.24±2.45 MJ/（m2·d）,has a significant gradient.Beam,diffuse and reflected components are quite different,with ratios of the annual average global radiation 84.1%,15.6% and 3% respectively.（3） Global radiation and its variability both decrease along the three terrain ladders from west to east.Atmospheric attenuation along with the elevation plays an important role in the pattern of clear-sky radiation.（4） Seasonal distributions of clear-sky radiation are asymmetry,with the percentage order of the annual average global radiation,summer（31.6%）spring（29.2%）autumn（21.9%）winter（17.3%）.Monthly changes of the clear-sky radiation share with the inverted ＂U＂-shaped curve.Monthly beam and diffuse radiation have similarly changing trend,but their proportion shifts with the atmospheric turbidity during the year.

关 键 词：r.sun模型 长江流域 晴日辐射 精度验证 时空分布 不确定分析 

分 类 号：P467[天文地球—大气科学及气象学]