IRS-1C LISS III land cover maps at different spatial resolutions used in real-time accidental air pollution deposition modelling

Remote-sensing scenes can provide information highly useful for real-time m odelling of the atmospheric deposition in the case of an accidental nuclear release. Accurate prediction of spatial patterns in the deposition is vita l to establish countermeasures to avoid unnecessary exposure of the public. This is demonstrated by a hypothesised case for a nuclear power plant in L ithuania. From classification analysis a number of land cover classes are m apped in an LRS-IC LISS III scene. The roughness of each land cover class i s assigned and used as input to a real-time dispersion model. Calculation r esults with input of a high-resolution roughness map provide the most reali stic deposition pattern. A scare analysis of degrading the land cover map i nto lower resolutions is performed. The atmospheric deposition model result s based on lower resolution roughness maps are compared and evaluated by th e so-called Dose Isopleth Correlation Area (DICA) method. The recommendatio n is that a l-km resolution is adequate for real-time deposition modelling. Furthermore, the land cover mapping should be performed with care. Tempora l variations in roughness at a seasonal time scale should be considered. (C ) 2001 Elsevier Science Inc. All rights reserved.