Monitoring the salt crusts in arid areas by satellite data processing in this research, monitoring the salt crusts of KASHAN and MAHARLOO arid areas by using LISSIII datas of IRS-P6 satellite was accomplished. After exerting essential corrections for visual inter pretation , contrast optimization and making pseudo-colorful images were used to specity the salt crusts. Then , according to the salt crusts’ spectral reflections in different bands and spectral rationing, RSCI (ratio salt crust index) and NDSCI (normalized different salt crust index ) were described. The purpose of submitting these indexes is to maximize the differences between spectral reflection and its background in order to make a high quality image for them to be distinctive. finally, by using threshold and error matrix , it was specified that RSCI and NDSCI indexes showed the best separation. The results showed that RSCI and NDSCI indexes are functional for monitoring the salt crusts of arid areas using mutti-spectral satellite data

The term urban heat island (UHI), described the phenomenon of climate change in urban areas compared with surrounding rural areas. UHI effects include: increasing in energy and water consumption, air pollution expansion and interfering in thermal comfort. Surface urban heat island (SUHI) contains patterns of land surface temperature (LST) in urban areas that has interaction with UHI in urban canopy layer and urban boundary layer and investigate with thermal remote sensing. SUHI has diurnal and seasonal variations so requires multi-temporal data to analysis SUHI. In this study, the multi-temporal MODIS (Aqua and Terra) data product were used to analyze the SUHI in day and night in Tehran metropolitan. Physical and biophysical surface properties such as: land cover/land use (LULC), elevation, albedo, vegetation index (NDVI) and impervious surfaces index (NDBI) were used to interpretation of the LST and SUHI changes. The results showed that SUHI in Tehran, has spatial-temporal diurnal and seasonal variation. So that during warm days the surface urban cool island (SUCL) is formed in Tehran. At night times, SUHI index values was different between 2 and 5 ° C (maximum in the spring). The results also showed that different of land cover thermal properties, albedo and elevation was the most important factors is the diurnal changes of SUHI while phonological changes of vegetation and albedo, was the most important factors in seasonal changes of SUHI.