Ziqian Wang, Juan Xu, Zhuoyu Zeng, Minling Ke, Xinhua Feng
{"title":"Understanding the 2022 Extreme Dragon-Boat Rainfall in South China from the Combined Land and Oceanic Forcing","authors":"Ziqian Wang, Juan Xu, Zhuoyu Zeng, Minling Ke, Xinhua Feng","doi":"10.1007/s13143-024-00356-6","DOIUrl":"10.1007/s13143-024-00356-6","url":null,"abstract":"<div><p>The most frequent and concentrated rainfall in the pre-flood season in South China usually occurs around the Dragon Boat Festival every year, locally known as ‘Dragon-boat Rainfall (DBR)’. In 2022, a record-breaking DBR attacked South China, causing disastrous flooding. We suggest that this extreme DBR was jointly regulated by the tropical convective forcing and Tibetan Plateau (TP) heating. Distinctly strong low-level southwesterlies and ascending motions over South China were the key atmospheric conditions. And the abnormal low-level southwesterlies were contributed by both the anomalous anticyclone over the western North Pacific and the anomalous westerlies at the southern side of the TP. On the one hand, during the period of 2022 DBR, stronger-than-normal convective forcing over the Maritime Continent induced the low-level anomalous anticyclone over the western North Pacific through triggering the meridional vertical circulation and further promoted the upward motions over South China. On the other hand, positive diabatic heating over the TP forced abnormal warm anticyclone in the mid-upper troposphere, more warm air advected downstream by the background westerlies, intensifying the upward motions over South China. Meanwhile, the TP heating could induce the anomalous low-level westerlies at the southern side of the TP, which further merged into and intensified the southwesterlies over South China and greatly enhanced the moisture transport and convergence there. Therefore, we highlight the strong thermal forcing over the TP, exerting a combined and amplified effect with the convective forcing over the Maritime Continent, dominated the record-breaking DBR in 2022.</p></div>","PeriodicalId":8556,"journal":{"name":"Asia-Pacific Journal of Atmospheric Sciences","volume":"60 4","pages":"1 - 14"},"PeriodicalIF":2.2,"publicationDate":"2024-03-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140149467","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Publisher Correction to: Assessment and Projection of Compound Wind and Precipitation Extremes in EC-Earth3 of CMIP6 Simulations","authors":"Xiaoyu Zhu, Jianping Tang, Yi Yang","doi":"10.1007/s13143-024-00360-w","DOIUrl":"10.1007/s13143-024-00360-w","url":null,"abstract":"","PeriodicalId":8556,"journal":{"name":"Asia-Pacific Journal of Atmospheric Sciences","volume":"60 4","pages":"605 - 605"},"PeriodicalIF":2.2,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142411480","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Yanan Fu, Jianhua Sun, Zhifang Wu, Tao Chen, Xiaodong Song, Shijun Sun, Shenming Fu
{"title":"Formation Mechanisms of the Extreme Rainfall and Mesoscale Convective Systems over South China during the Dragon Boat Rainy Season of 2022","authors":"Yanan Fu, Jianhua Sun, Zhifang Wu, Tao Chen, Xiaodong Song, Shijun Sun, Shenming Fu","doi":"10.1007/s13143-024-00357-5","DOIUrl":"10.1007/s13143-024-00357-5","url":null,"abstract":"<div><p>The formation mechanisms of the record-breaking rainfall event during the Dragon Boat Rainy Season (DBRS) of 2022 are comprehensively analyzed from the synoptic scale and the mesoscale perspectives. The extreme rainfall event is characterized by the highest rainfall amount since 1981, and an abnormal spatial distribution with much higher (lower) rainfall amount in the northern (southern) part of South China. The abnormal circulation and thermodynamic conditions are mainly responsible for the extreme rainfall. The favorite synoptic condition for rainfall is the combination of warm advection, frontal forcing, orographic lifting and low-level jet favor the convection development. The similar configurations repeatedly impact South China during the DBRS of 2022, causing multiple heavy rainfall events, leading to the extreme rainfall of the whole period. The abnormal moisture convergence together with the frontal zone, which is stronger than the climatology, results in the rainfall centers over the northern part of South China. 54.35% of the rainfall amount is related to mesoscale convective systems (MCSs) which mainly originate from four regions. The MCSs from the four regions are characterized by different formation peaks, spatial scales, lifetimes and propagations. The large-scale warm and moist air mass, the moistening caused by synoptic advection and the local diabatic heating are responsible for the increasing instability for the MCSs. The low-level jets play an important role in the formation of MCSs by providing moisture. The thermodynamic (dynamic) environmental conditions control the formation of MCSs in the afternoon (night).</p></div>","PeriodicalId":8556,"journal":{"name":"Asia-Pacific Journal of Atmospheric Sciences","volume":"60 4","pages":"1 - 18"},"PeriodicalIF":2.2,"publicationDate":"2024-03-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140117196","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Multiscale Variability of Autumn\u0000 Precipitation in Eastern Taiwan Modulated by ENSO, ISO, and TC Activity","authors":"Ching-Hsuan Wu, Wei-Ting Chen, Chien-Ming Wu","doi":"10.1007/s13143-024-00359-3","DOIUrl":"10.1007/s13143-024-00359-3","url":null,"abstract":"<div><p>This study investigates the multiscale variability of rainfall over\u0000 eastern Taiwan during October–November, focusing on the companion effect of tropical\u0000 cyclone (TC) activity in the South China Sea (SCS) and northeasterly monsoon flow.\u0000 The interannual variation of autumn rainfall is significantly influenced by the ENSO\u0000 Phase. During La Niña years, the moisture transport from the SCS-Philippine Sea to\u0000 eastern Taiwan is enhanced by the anomalous southeasterly winds owing to the\u0000 cyclonic flow over the SCS. The response of autumn rainfall to ENSO is contributed\u0000 by intraseasonal variability and the associated TC activity in SCS. During La Niña\u0000 years, the Madden–Julian Oscillation (MJO) convective areas during phases 4–7 shift\u0000 into the SCS-Philippine Sea, and the quasi bi-weekly oscillation (QBWO) convective\u0000 activity is enhanced around the north of Luzon Island. We categorize TCs moving\u0000 westward into or forming within the SCS into the groups causing significant rainfall\u0000 in eastern Taiwan or not (the rainfall and non-rainfall groups). The rainfall group\u0000 predominantly occurs during La Niña years in MJO phases 5. Both groups have similar\u0000 average TC intensities, but the rainfall group’s path and the associated cyclonic\u0000 circulation are placed more northward. Both groups of TCs coincide with QBWO’s\u0000 cyclonic circulation, but the cyclonic circulation associated with the rainfall\u0000 group stretched from the SCS to the Ryukyu Islands, favoring the moisture transport\u0000 from the Philippine Sea to eastern Taiwan. We concluded that, excluding direct TC\u0000 influences, the most favorable conditions for heavy rainfall in eastern Taiwan in\u0000 Autumn are La Niña years during MJO phases 4–5, when the coinciding of TCs with\u0000 appropriately structured QBWOs passing through the Bashi Channel or the Northern\u0000 Philippines into the SCS. A regression model is developed based on the diagnostics\u0000 in this study using vertically integrated moisture transport and divergence from\u0000 1000–700 hPa, which provide the basis of the storyline approach to estimate autumn\u0000 rainfall over eastern Taiwan from the future projection of global climate\u0000 models.</p></div>","PeriodicalId":8556,"journal":{"name":"Asia-Pacific Journal of Atmospheric Sciences","volume":"60 3","pages":"303 - 317"},"PeriodicalIF":2.2,"publicationDate":"2024-03-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"140117210","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}