Orographic effect and multiscale interactions during an extreme rainfall event

Author:

Baisya HimadriORCID,Pattnaik SandeepORCID

Abstract

Abstract Interaction of multiple oscillations of different time scales may result in severe weather events. The presence of orography can modulate the intensity of these events even further. Kerala witnessed one such heavy rainfall event in August, 2018, claiming 483 lives and damages worth INR 200 billion. This study focuses on the peak rainfall duration (13–17 August) when the departure from normal was 42%. Segregating moisture transport into its mean and perturbation terms show that an anomalous moisture channel over the Arabian Sea supplied continuous moisture to the Western Ghats (WG), whereas anomalous wind due to a monsoon depression advected moisture towards the southern peninsula. It is evident in the form of Moisture Flux Convergence (MFC) towers traversing along the Eastern Ghats before merging with the semi-permanent MFC feature over the WG. The presence of positive quasi bi-weekly oscillations and of Intra Seasonal Oscillations (ISO) aggravated the event as they complemented the anomalous moisture transport, with ISO constantly providing winds of the order of 2–3 ms−1. In addition, shedding of MFC towers by the depression is accredited to the synoptic scale oscillation.

Funder

Department of Science and Technology, Ministry of Science and Technology

IIT Bhubaneswar

Science and Engineering Research Board Government of India

Publisher

IOP Publishing

Subject

Atmospheric Science,Earth-Surface Processes,Geology,Agricultural and Biological Sciences (miscellaneous),General Environmental Science,Food Science

Reference28 articles.

1. Ramifications of atmospheric humidity on monsoon depressions over the indian subcontinent;Baisya;Sci. Rep.,2018

2. Land surface-precipitation feedback analysis for a landfalling monsoon depression in the Indian region;Baisya;J. Adv. Model. Earth Syst.,2017

3. The use of moisture flux convergence in forecasting convective initiation: historical and operational perspectives;Banacos;Weather Forecast.,2005

4. The ERA-Interim reanalysis: configuration and performance of the data assimilation system;Dee;Q. J. R. Meteorol. Soc.,2011

Cited by 16 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