基于气象指标SPI的洞庭湖流域洪旱灾害分析

Flood and drought disaster analysis in Dongting Lake basin based on meteorological index SPI

本文基于洞庭湖流域19个气象站1967—2017年的逐月降水数据,选用气象指标SPI(标准化降水指数)对洞庭湖流域洪旱灾害发生频率进行研究分析。结果显示:洞庭湖流域发生中度洪涝和中度干旱频率较高,高于重度洪涝、重度干旱。SPI-3和SPI-6监测洞庭湖流域洪旱灾害发生频率结果基本一致。重度洪涝主要集中于洞庭湖流域北部地区,重度干旱发生于南部地区,中度洪涝发生于洞庭湖流域西部地区,中度干旱发生于洞庭湖流域东部地区。研究SPI能够识别出洞庭湖流域近50年发生的特大洪水灾害和主要旱灾,对流域特大洪水事件监测和预报具有潜在的应用价值,同时可为其他流域旱涝监测与评估提供借鉴。

Based on the monthly precipitation data of 19 meteorological stations in Dongting Lake basin from 1967 to 2017,the frequency of flood and drought disasters in Dongting Lake basin is studied and analyzed by using meteorological index SPI(standardized precipitation index).The results show that the frequency of moderate flood and drought in Dongting Lake basin is higher than that of severe flood and drought.SPI-3 and SPI-6 have basically the same results in monitoring the frequency of flood and drought disasters in Dongting Lake basin.Severe flooding occurred mainly in the northern area of Dongting Lake basin,severe drought occurred in the southern area,moderate flooding occurred in the western area of Dongting Lake basin,and moderate drought occurred in the eastern area of Dongting Lake basin.The SPI study can identify the catastrophic floods and major droughts in Dongting Lake basin in the past 50 years,which has potential application value for monitoring and forecasting catastrophic floods in the basin,and can provide reference for monitoring and evaluating droughts and floods in other basins.