Features of Local Finite-Amplitude Wave Activity during Extreme Cold Waves over Eastern China

Author:

Shi Ning1ORCID,Ekwacu Samuel12,Fu Shiyi1,Song Jian1,Xing Shaoying1

Affiliation:

1. a Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Sciences, Nanjing University of Information Science and Technology, Nanjing, Jiangsu, China

2. b Uganda National Meteorological Authority, Kampala, Uganda

Abstract

Abstract The frequent occurrence of extreme cold waves under climate change has attracted widespread attention. Based on the Japanese 55-year Reanalysis daily dataset from 1958 to 2021, we use a newly developed dynamic metric, the local finite-amplitude wave activity (LWA), to explore the precursory signals, outburst conditions, and key dynamic features of extreme cold waves over eastern China from the perspective of synoptic climatology. The statistical results show that approximately 40% of extreme cold waves have the following features. First, the formation of significant positive LWA anomalies over the Balkhash–Baikal region is an evident precursory signal, which is accompanied by significant cold surface air temperature anomalies that accumulate over mid- and high-latitude Eurasia. Second, the appearance of extreme positive LWA anomalies over the region east of Lake Baikal (ELB) is necessary for subsequent outbursts of extreme cold waves. These extreme positive LWA anomalies indicate the meridionally enhanced planetary trough over East Asia and advection of the accumulated cold air masses southeastward to eastern China. Third, the evident positive change in the LWA anomalies over the ELB is mainly attributable to the convergence of the zonal LWA flux due to the zonal wind in the eddy-free state and Stokes drift flux over the eastern area of the ELB and the convergence of the meridional eddy heat flux over the western area. This study demonstrates that the LWA could be used as a simple and feasible metric for monitoring and forecasting extreme cold waves. Significance Statement Enhanced waviness in circulation usually occurs before and during the outburst of extreme cold waves over eastern China. With a state-of-the-art diagnostic tool, the local finite-amplitude wave activity (LWA), the present study reveals both precursory signals and outburst conditions of these extreme cold events from the perspective of synoptic climatology. This study not only deepens our understanding of the dynamic process for extreme cold events over eastern China but also offers a method for monitoring and forecasting those extreme events. Our work also provides a method for studying other extreme climate events that are closely related to large-amplitude circulation waviness over the middle and high latitudes.

Funder

National Natural Science Foundation of China

National Key R&D Program of China

Publisher

American Meteorological Society

Subject

Atmospheric Science

Reference32 articles.

1. Exploring recent trends in Northern Hemisphere blocking;Barnes, E. A.,2014

2. An objective technique for detecting large-scale tilted ridges and troughs and its application to an East Asian cold event;Bueh, C.,2015

3. Large-scale circulation features typical of wintertime extensive and persistent low temperature events in China;Bueh, C.,2011

4. On the two successive supercold waves straddling the end of 2020 and the beginning of 2021;Bueh, C.,2022

5. Local finite‐amplitude wave activity as an objective diagnostic of midlatitude extreme weather;Chen, G.,2015

Cited by 1 articles. 订阅此论文施引文献 订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3