نوع مقاله : مقاله پژوهشی
نویسنده
استادیار اقلیم شناسی، گروه جغرافیا، دانشکده ادبیات و علوم انسانی، دانشگاه فردوسی مشهد، مشهد، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسنده [English]
Extreme precipitation events act as the primary catalysts for flash floods, profoundly escalating hydrologic risks across Iran’s watersheds. This profound impact necessitates rigorous, targeted evaluation. The present study initially investigated the efficacy of GPM-IMERG satellite estimates (2001-2020) in capturing basin-scale spatial precipitation distributions. We then deployed Shannon entropy as a data-driven weighting framework to quantify the vulnerability of these basins to extreme precipitation. Dataset validation revealed a distinct spatial dichotomy. Across the Zagros slopes, GPM-IMERG products demonstrated robust correlation and high accuracy in replicating spatial precipitation structures, proving highly adept at monitoring extreme events. Conversely, systematic estimation errors plagued the data along the Caspian coastal strip and within arid inland basins. Analyzing a suite of extreme precipitation indices (Rx1day, R10mm, R20mm, and SDII) highlighted that western and southwestern mountainous catchment most notably Karkheh, Great Karun, and Jarahi-Zohreh concurrently endure peak intensity and frequency levels. The southern coastlines present a different dynamic altogether: abrupt surges in intensity indices occur alongside a relatively low frequency of occurrences. Ultimately, mapping vulnerability by applying Shannon entropy to the extreme indices matrix yielded clear territorial delineations. Low vulnerability zones encompass 46.5% of the country, while 30% falls into moderate categories and 23.5% faces high-risk conditions. A contiguous belt spanning the western Zagros foothills and southern shores concentrates 12.7% of Iran’s area within the severe to extreme vulnerability classifications. By contrast, central and eastern basins exhibit the least spatial variability and lowest extreme magnitude, translating to the lowest-risk precipitation regime nationwide.
کلیدواژهها [English]
)