نوع مقاله : پژوهشی
1 دانشیار گروه مهندسی آب، دانشکدۀ کشاورزی و منابع طبیعی، دانشگاه لرستان
2 دانشیار، گروه انرژیهای نو و محیط زیست، دانشکدۀ علوم و فنون نوین، دانشگاه تهران
3 دانش آموختۀ کارشناسی ارشد سنجش از دور و GIS، دانشگاه تهران
4 دانشجوی دکتری سازه های آبی، دانشکدۀ کشاورزی و منابع طبیعی، دانشگاه لرستان
5 دانشجوی دکتری علوم و مهندسی آبخیز، دانشکدۀ منابع طبیعی و علوم زمین، دانشگاه کاشان
عنوان مقاله [English]
Studying and evaluating changes in snow cover, as one of the most significant sources of water supply is very important. Due to the conditions of inaccessible mountainous areas, it is not possible to make permanent ground measurements to estimate snowfall resources and form a database. Therefore, the use of satellite imagery in identifying snow-covered areas and evaluating its changes is very important and necessary. In this study, satellite imagery of MODIS sensor in Marber Basin located in the south of Isfahan province for the 20-year period from 2000 to 2019 was used. It is noteworthy that in this study, the Google Earth Engine system, or GEE, was used, which is a new and very useful system. In the present study, more than 7000 images of daily snow cover were used, which are available in GEE in the shortest time. TFPW-MK test was used to evaluate the trend of snow cover changes. In this study, in addition to programming and calling images and extracting snow cover values in the engine system and process analysis by performing TFPW-MK test, ArcGIS10.5 software was also used in preparing the outputs. The results showed that the trend of changes in snow cover levels during the mentioned 20-year period has been decreasing, so that from about 120 square kilometers to less than 60 square kilometers in 2018, according to the percentage of trust (p-column in The TFPW method has a significant negative trend at the level of 5% in January and August and a significant negative trend at the level of 10% in June. The annual trend was also examined by TFPW test and shows a significant negative trend at the level of 5%.