نوع مقاله : مقاله پژوهشی
نویسندگان
1 گروه جغرافیا، دانشکده علوم انسانی، دانشگاه زنجان، زنجان، ایران.
2 دانشجوی دکترای اقلیم شناسی، دانشکده علوم انسانی، گروه جغرافیا، دانشگاه زنجان، زنجان، ایران.
چکیده
کلیدواژه‌ها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Cloudiness is of particular importance among other climatic elements and is one of the important issues in predicting climate change on a global and regional scale. The purpose of this study is to investigate the spatial distribution and estimate the long-term average of cloudiness on a seasonal and monthly time scale in the geographical area of Iran's atmosphere. MISR products were used during the years 2001-2019. The cloud products used were extracted with monthly temporal resolution and spatial resolution of 0.5° x 0.5° and after quality control and preprocessing, were used to build network layers. Cloud cover data from 44 synoptic meteorological stations were used to verify the accuracy of the cloud data of the MISR sensor.Based on the results; The average percentage of cloudiness in Iran's atmosphere is about 25%, which is a with few cloud country compared to the global average cloudiness (50%) of Iran. In the long-term study, the maximum cloudiness was estimated on the southern and western coasts of the Caspian Sea and then in the highlands of Azerbaijan, Zagros and Khorasan. Among the seasons, the highest cloud fraction was estimated in winter and the lowest in summer. On a monthly time scale, it was found that the highest/ lowest amount of cloud fraction is related to February/September. These differences indicate changes in the weather during different months of the year. Another result is the decreasing trend of cloud fraction the study period, which is important in terms of global warming and climate change.
کلیدواژه‌ها [English]
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