Effect of sub-cloud evaporation on precipitation in the Tianshan Mountains (Central Asia) under the influence of global warming |
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| Authors: | Haiyan Chen Yaning Chen Dalong Li Weihong Li |
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| Institution: | 1. College of Geography and Environmental Science, Hainan Normal University, Haikou, China;2. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China |
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| Abstract: | It is crucial for accurately describing the precipitation patterns and their underlying mechanisms to optimise the hydro-climatic model parameters and improve the accuracy of precipitation forecasting. Based on 212 precipitation samples collected during August 2015 to July 2016 in the mid-mountain region of the Manasi River Basin in the northern slope of the Tianshan Mountains, we estimated the effect of sub-cloud evaporation on precipitation, analysed the factors that influence the sub-cloud evaporation, and modelled the response of sub-cloud evaporation to global warming. The mean remaining raindrop mass fraction after evaporation (f ) in this region is 94.39%. The mean deviation between d-excess (Δd ) of ground precipitation and raindrops under cloud is ?4.22‰. The intensity of sub-cloud evaporation is the highest in summer. There is a significant positive correlation between f and Δd (0.72‰/%). The relative humidity and diameter of raindrops were observed to have a direct influence on the intensity of sub-cloud evaporation. The temperature was observed to influence the intensity of sub-cloud evaporation indirectly by influencing the relative humidity and diameter of raindrops. Global warming will increase the intensity of sub-cloud evaporation in the Tianshan Mountains, especially for small precipitation events. |
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| Keywords: | global warming isotope precipitation sub-cloud evaporation Tianshan Mountains |
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