Spatial differentiation in absorbed solar radiation in the Ojców National Park

anglais. The research presents the analysis of spatial variations of absorbed solar radiation in the Ojców National Park in the south part of Krakowsko-Częstochowska Upland in Poland. This area is characterized by varied diverse relief The solar radiation budget was estimated on the basis of multispectral satellite images and the solar radiation model implemented to the Geographical Information Systems (GIS). The materials used in the research were digital terrain model (DTM) with spatial resolution of 20 m/pixel and multispectral satellite images LANDSAT-7. The digital terrain model was used to mark indispensable topography parameters like elevation, slope, aspect and sky factor. The modelling was realized in a few stages. During the first stage the spatial data base for the tested area was prepared. During the second one the flux of global solar radiation was calculated. On the basis of the satellite images LANDSAT-7 the value of surface albedo α was calculated. It was found that in the case of the Ojców National Park, highly diverse relief seems to be the main factor influencing controlling the values of absorbed solar radiation. The solar radiation budget is also dependent on the albedo. Despite a considerable diversity of land cover and land use in the Ojców National Park, the impact of albedo on absorbed solar radiation value is decidedly less significant than the relief.

5

1-11