鄱阳湖流域水旱灾害对气候变化的响应

Response of flood and drought disasters to climate change in Poyang Lake Basin

摘要

【目的】气候变暖将影响水旱灾害的发生频率和强度，研究鄱阳湖流域洪水、干旱灾害发生频率和强度对气候变暖的响应。【方法】构建包括流域降水量以及长江流量等主要致灾因素在内的水旱灾害强度数学模型，计算1960—2022年鄱阳湖流域夏季洪水、春季和夏季干旱灾害强度；比较气候变暖前后水旱灾害发生频率与强度；认识水旱灾害对气候变化的响应情况。【结果】1996年以后鄱阳湖流域气候变暖，丰水期降水与地表径流减少1.9%~5.1%、枯水期增加1.1%~9.1%;气候变暖对夏季洪水与春季干旱发生频率和强度影响有限，但显著增加了夏季干旱发生频率和灾害强度，发生频率由变暖前的16%,增加到变暖后的28%。【结论】鄱阳湖流域水旱灾害强度模型求解结果符合客观实际，水旱灾害发生时间、强度与记载的实际灾情基本一致，模型具有一定科学价值，结果较为可信。如果水旱灾害强度等级阈值采用统计学方法确定，将有助于模型应用推广。

Abstract

[Objective] Climate change will affect the frequency and intensity of floods and droughts. The impact of climate warming on the frequency and intensity of floods and droughts is empirically studied in the Poyang Lake Basin. [Methods] A flood and drought disaster intensity model is constructed, including the main disaster causing factors such as precipitation in the Poyang Lake Basin and the flow of the Yangtze River. This model is used to calculate the intensity of summer floods, spring and summer droughts in the Poyang Lake Basin from 1960 to 2022. By comparing the frequency and intensity of floods and droughts before and after climate change, the response of floods and droughts to climate change is obtained. [Results] After 1996, the climate has warmed in the Poyang Lake Basin, with precipitation and surface runoff decreasing by 1.9%~5.1% during the wet season and increasing by 1.1%~9.1% during the dry season. Climate warming will have a very limited impact on the frequency and intensity of summer floods and spring droughts, but will significantly increased the frequency and intensity of summer droughts, from 16% before warming to 28% after warming. [Conclusion] The solution result of the intensity model for flood and drought disasters in the Poyang Lake Basin are in line with the actual situation, and the time and intensity of flood and drought disasters are basically consistent with the recorded actual disaster situation. The model may have scientific value and the result are reliable. If statistical method well be used to determine the intensity classification of flood and drought disasters, it will promote the application and promotion of the model.

关键词

气候变暖 / 水旱灾害 / 灾害强度模型 / 鄱阳湖流域 / 洪水 / 长江流域 / 降雨

Key words

climate change / flood and drought disasters / disaster intensity model / Poyang Lake Basin / flood / Yangtze River Basin / rainfall

基金资助

国家自然科学基金项目(41261053)

江西省重点课题(202023ZKDT03)