Analysis of spatiotemporal characteristics of meteorological drought in Taohe River Basin based on SPEL
Based on the monthly temperature and precipitation data from 1976 to 2020 in the Taohe River Basin,the standardized precipitation evapotranspiration index(SPEI)values at seasonal and annual scales were calculated.The time series stationariness test method and drought frequency method were used to quantitatively analyze the variation pattern and spatial distribution characteristics of different levels of meteorological drought frequency at seasonal and annual scales.The randomness and stability of the spatiotemporal distribution of meteorological drought at the annual scale were analyzed using the cloud model.The results show that the frequencies of drought in all four seasons are about 30％,with droughts mainly occurring in spring and winter.At the annual scale,the basin is dominated by mild and moderate droughts,which have a high occurrence frequency,while severe and extreme droughts occur less frequently,indicating an overall dry tendency.In terms of spatial distribution,droughts occur mainly in the middle and lower reaches of the basin.During the period from 1976 to 2020,the degree of drought in the basin weakened,with a stable trend and small fluctuations in drought severity.
meteorological droughtspatiotemporal characteristicsSPEIcloud modelTaohe River Basin
万方数据
维普
