气候变化领域集成服务门户(CCPortal): Simulation of a mesoscale convective system over Northern India: Sensitivity to convection partitioning in a regional NWP model

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DOI	10.1016/j.dynatmoce.2020.101162
	Simulation of a mesoscale convective system over Northern India: Sensitivity to convection partitioning in a regional NWP model
	Francis T.; Jayakumar A.; Mohandas S.; Sethunadh J.; Reddy M.V.; Arulalan T.; Rajagopal E.N.
发表日期	2020
ISSN	03770265
卷号	92
英文摘要	Simulations of a mesoscale convective system (MCS), which propagated across Northern India on 2nd May 2018 - leading to many fatalities when the gust front knocked down homes and tore apart building roofs - have been performed using the National Centre for Medium Range Weather Forecasting (NCMRWF) Unified Model – Regional (4 km horizontal grid spacing), to evaluate the model's convective treatments. Though the model captures many of the qualitative and quantitative features, it slightly lags behind the observed MCS organisation and movement, produces lesser precipitation, and lacks the spatial separation between two adjacent organised convective systems in the satellite observations – leading to a faintly offset MCS track. Sensitivity simulations are then performed, for this non-equilibrium MCS case, with different partitioning between parametrized and explicit convection to assess the reliance of the convective treatments on the large-scale environment, as well as to test the notion of a breakdown of convective parametrization at the mesoscale model resolution. Fully parametrized (FP) convection produces even lesser rainfall and are dominated by orographic precipitations along the foot hills of Himalayas with no any trace of the MCS. Fully explicit (FE) convection realistically simulates most of the prominent convective cells and enhance precipitation along the MCS track that agree better with the observations, though the ‘two lobes’ of intense precipitation are not resolved; instead it produces a squall line of precipitation. The FE configuration generates the most vigorous convective updraft, along with a vertical shear that is tilted westward. The simulation with partially parametrized and partially explicit convection resembles the fashion in the FP and FE scenarios, with a transition over the duration of the run from parametrized to explicit precipitation. The results are in line with the notion from previous studies; that the majority of successful explicit simulations of mesoscale organisation are those associated with strong large-scale forcing for convection, wherein resolved vertical motions are sufficient to minimise delays in onset. © 2020 Elsevier B.V.
英文关键词	Mesoscale convective systems; NWP; Thunderstorms; Unified model
语种	英语
scopus关键词	Storms; Convective parametrization; Explicit precipitations; Horizontal grid spacing; Intense precipitation; Mesoscale Convective System; Orographic precipitation; Satellite observations; Sensitivity Simulation; Weather forecasting; atmospheric convection; atmospheric modeling; computer simulation; convective system; mesoscale meteorology; orographic effect; sensitivity analysis; weather forecasting; India
来源期刊	Dynamics of Atmospheres and Oceans
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/178291
作者单位	National Centre for Medium Range Weather Forecasting, Noida, 201 309, India
推荐引用方式 GB/T 7714	Francis T.,Jayakumar A.,Mohandas S.,et al. Simulation of a mesoscale convective system over Northern India: Sensitivity to convection partitioning in a regional NWP model[J],2020,92.
APA	Francis T..,Jayakumar A..,Mohandas S..,Sethunadh J..,Reddy M.V..,...&Rajagopal E.N..(2020).Simulation of a mesoscale convective system over Northern India: Sensitivity to convection partitioning in a regional NWP model.Dynamics of Atmospheres and Oceans,92.
MLA	Francis T.,et al."Simulation of a mesoscale convective system over Northern India: Sensitivity to convection partitioning in a regional NWP model".Dynamics of Atmospheres and Oceans 92(2020).