气象科学2024，Vol.44Issue(2)：292-300,9.DOI:10.12306/2022jms.0080
长江中下游地区骤发干旱与缓发干旱特征对比研究
Comparisons on the characteristics of flash drought and slowly-evolving drought in the middle and lower reaches of Yangtze River
摘要
Abstract
Based on the reanalysis of soil moisture,atmospheric isobaric surface data,and CMIP6 model data,the principle of atmospheric column water budget and the attribution method were used to identify the grid flash drought and slowly-evolving drought in the middle and lower reaches of the Yangtze River from 1979 to 2020,moreover,their spatial distribution and statistical characteristics were also analyzed.Furthermore,the development process of regional flash drought and slowly-evolving drought events as well as the influence of human factors were diagnosed.Results show that the flash drought occurrs frequently in the region,mainly in the south areas,with strong intensity,and mostly develops in summer.The slowly-evolving drought occurrs less,mainly in the north areas,with weak intensity,and mostly develops in autumn.The atmospheric column water vapor net divergence plays an important role in the development of the two types of drought.In the development process of flash drought,the atmospheric column water vapor net divergence is stronger,which results in a larger difference between evapotrans-piration and precipitation,and the decrease rate of soil moisture is faster than the slowly-evolving drought.In the summer of 2019,a large-scale flash drought event occurred in the middle and lower reaches of the Yangtze River.During the development stage,the westward extension of subtropical high enhanced the divergence of wind field in the regional atmospheric column,resulting in strong atmospheric column water vapor net divergence and rapid development of drought.A regional slowly-evolving drought event occurred in 2010/2011.During the autumn development stage,the wind field near the ground layer was a weak anticyclonic circulation.The divergence of wind field was weak,and the atmospheric column water vapor net divergence was small,which led to the slowly-evolving drought.Human activities contributed more to the flash drought event in 2019 than to the slowly-evolving drought event in 2010/2011.关键词
骤发干旱/缓发干旱/发展阶段/水汽净辐散Key words
flash drought/slowly-evolving drought/development stage/net divergence of water vapor分类
天文与地球科学引用本文复制引用
施欣池,余锦华,张旭煜..长江中下游地区骤发干旱与缓发干旱特征对比研究[J].气象科学,2024,44(2):292-300,9.基金项目
国家自然科学基金委气象联合基金资助项目(U2342208) （U2342208）
国家重点研发计划资助项目(2018YFC1507704 （）
2018YFC1505804) （）
