【摘 要】
：
旱涝灾害是长江中游地区社会经济发展的瓶颈之一,旱涝灾害在近二三十年来发生了显著变化,但对其演变规律和成因还缺乏全面研究.以长江中游梅雨锋暴雨幕阜山地区典型流域隽水河为研究对象,基于标准化径流指数(standardized runoff index,SRI),利用趋势和变点检验、交叉小波变换、增强回归树机器学习(boosted regression tree,BRT)等方法探究典型流域旱涝与旱涝/涝旱急转演变规律及其驱动因子.研究发现:1)基于1、3、6、12个月4个时间尺度的SRI变化表明,1973-20
【机 构】
：
武汉大学水利水电学院,湖北武汉430072;武汉大学水资源与水电工程科学国家重点实验室,湖北武汉430072;湖北省水利水电科学研究院,湖北武汉430070
论文部分内容阅读
旱涝灾害是长江中游地区社会经济发展的瓶颈之一,旱涝灾害在近二三十年来发生了显著变化,但对其演变规律和成因还缺乏全面研究.以长江中游梅雨锋暴雨幕阜山地区典型流域隽水河为研究对象,基于标准化径流指数(standardized runoff index,SRI),利用趋势和变点检验、交叉小波变换、增强回归树机器学习(boosted regression tree,BRT)等方法探究典型流域旱涝与旱涝/涝旱急转演变规律及其驱动因子.研究发现:1)基于1、3、6、12个月4个时间尺度的SRI变化表明,1973-2018年隽水河流域趋向变湿润,随时间尺度增加,极端旱涝发生频率增加,旱涝持续时间延长;2)1990年之后,涝频率、旱涝烈度和强度呈增大趋势;3)旱涝/涝旱急转事件主要发生于3-10月,其历时、烈度和强度均呈增加趋势;4)基于机器学习方法进一步归因,发现气象因素中降雨和蒸发对旱涝/涝旱急转烈度变化的贡献率较大,大气环流因素中西太平洋暖池强度指数(Western Pacific warm pool strength index,WPWPSI)、西太平洋副高强度指数(Western Pacific subtropical high intensity index,WPSHII)、太阳黑子指数(total sunspot number index,TSNI)和南海副高强度指数(South China Sea subtropical high intensity index,SCSSHII)与烈度变化较为相关,对典型事件分析发现大气环流的异常变化在一定程度上导致了旱涝的异常变化.
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