| چکیده انگلیسی مقاله |
Glaciers influenced by climatic factors and therefore as an important indicator in the study of climate change are studied. Although morphometric analyzes of glaciers based on the analysis of optical satellite data can provide an opportunity to measure ice outcrops, but the identification and determination of the buried glaciers underneath the glacial debris and, consequently, the determination of the actual glacial body and their parameters, including the level and volume of the glaciers, are not possible based on optical satellite imagery. On the other hand, the existence of an ice cooling source underneath the glacial debris, which leads to a significant reduction in the surface temperature of the glacial debris, is a distinguishing feature for the separation of covered glaciers. In this research, the expansion of natural glaciers of Zardkuh Mountain has been determined by the combined analysis of thermal and optical data (Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS) of Landsat 8) based on Split Window Algorithm and digital elevation data. For this purpose, after radiometric and geometric corrections, land surface temperature (LST) were calculated based on the calculated Normalized Difference Vegetation Index (NDVI) and Land Surface Emissivity (LSE). Based on the results of this study, the area of the glaciers (surface and buried ice) were 201 hectares in August 2017, which in comparison with previous studies, shows a significant decrease in the past decade. |