Monsoon precipitation characteristics and extreme precipitation events over Northwest India using Indian high resolution regional reanalysis

Aggarwal, D and Attada, R and Shukla, KK and Chakraborty, R and Kunchala, RK (2022) Monsoon precipitation characteristics and extreme precipitation events over Northwest India using Indian high resolution regional reanalysis. In: Atmospheric Research, 267 .

	PDF atm_res_267_2022.pdf - Published Version Restricted to Registered users only Download (12MB) | Request a copy
	Microsoft Word 1-s2.0-S0169809521005494-mmc1.docx - Published Supplemental Material Restricted to Registered users only Download (1MB) | Request a copy

Abstract

Northwest India, known as the breadbasket of the country, is extremely vulnerable to ramifications of extreme rainfall events (EREs) such as flash floods, landslides, agricultural and infrastructural damages. Nevertheless, the characteristics of EREs are less explored over Northwest India compared to other parts of the country. Hence, this study investigates the spatiotemporal variability of EREs using India's first highest resolution regional atmospheric reanalysis, Indian Monsoon Data Assimilation and Analysis (IMDAA) during Indian Summer Monsoon (ISM) for the period 1979�2018. Prior to understanding the EREs, we evaluated IMDAA's ability to represent general ISM characteristics using reanalysis and observations. Our analysis reveals that IMDAA realistically represents the ISM salient features along with a more accurate spatial distribution of summer precipitation compared to India Meteorological Department (IMD) observations, albeit with some overestimations. The mean ISM precipitation over Northwest India is found to be increasing significantly at 95 confidence level. Furthermore, EREs from IMD and TRMM exhibit increasing trends over Northwest India, which also conforms with IMDAA results (one event every two years). The rising (declining) trend in convective available potential energy (convective inhibition energy) signifies that the atmosphere over Northwest India is becoming more unstable during ISM. This enables it to hold more moisture, which is transported to the region from Bay of Bengal through cyclonic vorticity over Central India. Finally, the inter-parameter correlation analysis reveals that IMDAA reanalysis has succeeded in better representation of the physical linkages among moisture availability, instability, and convective precipitation formation over Northwest India compared to the global reanalysis products such as ERA5. © 2021

Item Type:	Journal Article
Publication:	Atmospheric Research
Publisher:	Elsevier Ltd
Additional Information:	The copyright for this article belongs to Elsevier Ltd
Keywords:	Atmospheric thermodynamics; Potential energy; Rain; Rain gages, Data assimilation; Extreme rainfall; Extreme rainfall event; High resolution; Indian monsoon; Indian monsoon data assimilation and analyse; Indian summer monsoon; Northwest india; Rainfall event; Reanalysis, Moisture
Department/Centre:	Division of Mechanical Sciences > Divecha Centre for Climate Change
Date Deposited:	20 Jan 2022 06:35
Last Modified:	20 Jan 2022 06:35
URI:	http://eprints.iisc.ac.in/id/eprint/70963

Actions (login required)

View Item