Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation （DSR） quantity of rugged terrain is very complex. Based on digital elevation model （DEM） data...Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation （DSR） quantity of rugged terrain is very complex. Based on digital elevation model （DEM） data and meteorological observations, a distributed model for calculating DSR over rugged terrain is developed. This model gives an all-sided consideration on factors influencing th a resolution of 1 km × 1 km for thDSR. Using the developed model, normals of annual DSR quantity wie Yellow River Basin was generated, with DEM data as the general characterization of terrain. Characteristics of DSR quantity influenced by geographic and topographic factors over rugged terrain were analyzed thoroughly. Results suggest that： influenced by local topographic factors, i.e. azimuth, slope and so on, and annual DSR quantity over mountainous area has a clear spatial difference; annual DSR quantity of sunny slope （or southern slope） of mountains is obviously larger than that of shady slope （or northern slope）. The calculated DSR quantity of the Yellow River Basin is provided in the same way as other kinds of spatial information and can be employed as basic geographic data for relevant studies as well.展开更多
This study investigates the spatial distribution of direct solar irradiation on rugged terrain over Pakistan. Digital elevation model (DEM), observational data of solar radiation from 6 meteorological observatories lo...This study investigates the spatial distribution of direct solar irradiation on rugged terrain over Pakistan. Digital elevation model (DEM), observational data of solar radiation from 6 meteorological observatories located in Pakistan and 5 meteorological observatories located in China were used in the present study. This conjunction is based on the same climatic conditions. MODIS Level-2 (L2) cloud fraction products and observational data of cloud cover from 21 meteorological observatories in Pakistan were incorporated to quantify the cloud cover influences on solar radiation amount and spatial distribution. The emerging field of remote sensing and GIS makes it possible to calculate solar radiation with finer spatial resolution and better understanding of terrain and cloud effects. ArcGIS with RS platform were used to simulate the model for direct solar radiation for the first time over Pakistan region. The results show clear quantitative influences of local topography and cloud cover on the DSR. Similarly, the area (east of Indus river) affected by monsoon receives less solar radiation during summer compared to the west of the Indus River.展开更多
文摘Due to the influences of local topographical factors and terrain inter-shielding, calculation of direct solar radiation （DSR） quantity of rugged terrain is very complex. Based on digital elevation model （DEM） data and meteorological observations, a distributed model for calculating DSR over rugged terrain is developed. This model gives an all-sided consideration on factors influencing th a resolution of 1 km × 1 km for thDSR. Using the developed model, normals of annual DSR quantity wie Yellow River Basin was generated, with DEM data as the general characterization of terrain. Characteristics of DSR quantity influenced by geographic and topographic factors over rugged terrain were analyzed thoroughly. Results suggest that： influenced by local topographic factors, i.e. azimuth, slope and so on, and annual DSR quantity over mountainous area has a clear spatial difference; annual DSR quantity of sunny slope （or southern slope） of mountains is obviously larger than that of shady slope （or northern slope）. The calculated DSR quantity of the Yellow River Basin is provided in the same way as other kinds of spatial information and can be employed as basic geographic data for relevant studies as well.
文摘This study investigates the spatial distribution of direct solar irradiation on rugged terrain over Pakistan. Digital elevation model (DEM), observational data of solar radiation from 6 meteorological observatories located in Pakistan and 5 meteorological observatories located in China were used in the present study. This conjunction is based on the same climatic conditions. MODIS Level-2 (L2) cloud fraction products and observational data of cloud cover from 21 meteorological observatories in Pakistan were incorporated to quantify the cloud cover influences on solar radiation amount and spatial distribution. The emerging field of remote sensing and GIS makes it possible to calculate solar radiation with finer spatial resolution and better understanding of terrain and cloud effects. ArcGIS with RS platform were used to simulate the model for direct solar radiation for the first time over Pakistan region. The results show clear quantitative influences of local topography and cloud cover on the DSR. Similarly, the area (east of Indus river) affected by monsoon receives less solar radiation during summer compared to the west of the Indus River.
