Abstract:This study investigates the characteristics and impacts of the seasonally consecutive drought in Guizhou Province during 2022-2023 with using the data of station observation, atmospheric reanalysis and sea surface temperature and the identification methods of high temperature processes, meteorological drought composite index (MCI), and regional drought processes and discuss the potential issues in drought monitoring services. Main results are as follows. The seasonally consecutive drought from August 13 of 2022 to February 21 of 2023 is the most intense one with the second longest duration and the greatest impact in Guizhou since 1961. The temperatures in summer and autumn of 2022 are both the highest during the same period since 1961 and also the high temperature processes are the strongest and most frequent since 1961. The precipitation from July of 2022 to February of 2023 is the lowest during the corresponding historical period.The western Pacific subtropical high was stronger and located more westward in summer and autumn of 2022, and temporarily connected with the Iranian high to form a high-pressure dam, under which Guizhou was controlled and influenced. The La Ni?a-like cold SST anomaly was conducive to a stronger summer monsoon and a northerly shift of the rain belt, resulting in less precipitation in Guizhou Province. The drought has significantly affected power supply and water usage for production and daily life.Both the MCI and the agricultural drought index provide good indications for the initial occurrence and development stage of drought. For persistent drought, especially starting from the rainy season, it is necessary for both indices to supplement and re-correct the previous water balance calculation. Severe droughts occurring in main rainy season have a more profound impact than those in other seasons.
