陕西省山地日照时间的空间分布特征  

The Spatial Distribution of Sunshine Duration of Mountain Terrain

作　　者：孙娴[1] 王娟敏[1] 姜创业[1] 程路[1] 

机构地区：[1]陕西省气候中心,西安710015

出　　处：《自然资源学报》2010年第4期625-635,共11页Journal of Natural Resources

基　　金：中国气象局气象新技术推广重点项目(CMATG2006Z10)

摘　　要：基于100 m×100 m分辨率的DEM数据,根据太阳光线与起伏地形之间的几何关系,全面考虑坡度、坡向、地形遮蔽等地形因子对可照时间的影响,通过数值模拟,确定山区可照时间计算模型;同时利用常规气象站资料考虑大气对日照时间的影响,建立陕西省山区日照时间估算模型。采用交叉验证和个例年分析法进行模型验证,模型的精度和稳定性均较好。通过模型计算陕西省100 m×100 m分辨率各月可照时间、气候平均日照时间的空间分布。结果表明:局地地形对日照时间空间分布影响比较明显,山区可照时间与同纬度平地相比明显差异,表现出可照时间的非地带性分布特征;尤以冬季地形作用最显著;夏季影响最弱;同时年日照时间呈现出北高南低的空间分布特征,但局地地形因子的影响依然存在。最后详细探讨了坡度、坡向、地形遮蔽等因子对山区日照时间的局地影响规律。Sunshine duration over mountain terrain is an important component of the global radiation reaching the earth.The sunshine duration quantity reaching the rugged terrain is influenced not only by many geographical and local topographic factors but also atmospheric factors.This paper,using the DEM（digital elevation model） data as input,based on the geometric character between sunray and topography,and giving an all-sided consideration on geographical factors,local topographic factors such as azimuth and slope angle of a titled surface and the screening effect of surrounding terrains,by numerical simulation,calculates the possible sunshine duration（SD）.At the same time,it uses observational data sets of routine meteorology to reflect the impact of the sunshine duration.A distributed model for calculating sunshine duration over mountain terrain was developed.Shaanxi Province is exampled for mountainous area,with a resolution of DEM data as the general characterization of the terrain.Using this model,monthly SD with a resolution of 100 m×100 m for the mountain topography of Shaanxi Province is calculated.Results suggested that terrain has robust effect on SD,particularly in winter when a lower sun elevation angle exists.This project may provide a new methodology for solar radiation resource investigation and evaluation using GIS.

关 键 词：日照时间 山地 分布式 陕西省 

分 类 号：P422.11[天文地球—大气科学及气象学]