Role of local absorbing aerosols in modulating Indian summer monsoon rainfall

被引：4

作者：

Asutosh, A. ^{[1
,2
]}

Vinoj, V. ^{[1
]}

机构：

[1] Indian Inst Technol Bhubaneswar, Sch Earth Ocean & Climate Sci, Bhubaneswar 752050, Odisha, India

[2] Natl Ctr Atmospher Res, Boulder, CO 80301 USA

来源：

SCIENCE OF THE TOTAL ENVIRONMENT | 2024年 / 910卷

基金：

美国海洋和大气管理局;

关键词：

Absorbing aerosols; Dust; Black carbon; Radiative forcing; Rainfall; Dynamics; REGIONAL CLIMATE MODEL; DUST AEROSOLS; DESERT DUST; MIDDLE-EAST; SOUTH-ASIA; REGCM4; SIMULATIONS; SENSITIVITY; ABSORPTION; PARTICLES;

D O I：

10.1016/j.scitotenv.2023.168663

中图分类号：

X [环境科学、安全科学];

学科分类号：

08 ; 0830 ;

摘要：

Absorbing aerosols and their impact on the Indian monsoon system is highly complex and demands more scientific understanding. Our study using a chemistry-coupled regional climate model (RegCM 4.5) with idealized experiments observed that natural and anthropogenic absorbing aerosols (i.e., dust and carbonaceous aerosols) reduce monsoon precipitation in a seasonal time scale. More than 1 mm day(-1) decline in mean summertime rainfall was observed over parts of the central Indian region and Indo-Gangetic plane for dust aerosol. A substantial reduction in the land-sea pressure gradient and lower tropospheric moisture distribution were found to control the observed modulation in rainfall. Near-surface wind circulation responded distinctly to natural (dust) and anthropogenic (carbonaceous) aerosols. The dust forcing weakened the monsoon trough by creating an anomalous anticyclonic circulation. The Northern Arabian Sea acted as a moisture source for the carbonaceous aerosol forcing. Intraseasonal rainfall over central India appeared to have a sharp reduction for dust forcing during early June, with a moderate increase for carbonaceous aerosols. Such quantification is essential for understanding the impact of aerosol forcing on regional climate change and the water cycle and has implications for emissions management and mitigation policies.

引用

页数：9