The impact of Covid-19 lockdown measures on the Indian summer monsoon
Bibliographic Data
| ID | 15545115 |
|---|---|
| Authors | Suvarna Fadnavis (0000-0003-4442-0755, Indian Institute of Tropical Meteorology, corresponding author), T P Sabin (Indian Institute of Tropical Meteorology), Alexandru Rap (0000-0002-2319-6769, University of Leeds), Rolf Müller (0000-0002-5024-9977, Forschungszentrum Jülich), Anne Kubin (0000-0003-4120-3819, Leibniz Institute for Tropospheric Research), Bernd Heinold (0000-0001-7963-3932, Leibniz Institute for Tropospheric Research) |
| Year | 2021 |
| Volume | 16 |
| Issue | 7 |
| Pages | 074054-074054 |
| Publication date | 2021-07-01 |
| Peer Reviewed | Yes |
| Open Access | Yes |
| Type | ARTICLE |
| Venue | Environmental Research Letters (JOURNAL) |
| Journal identifiers | ISSN: 1748-9326 • E-ISSN: 1748-9326 |
| Publisher | IOP Publishing (PUBLISHER • GB) |
| DOI | 10.1088/1748-9326/ac109c |
| OpenAlex | W3180197919 |
| Language | EN |
| Citations received | 2 |
| References cited | 51 |
Aerosol concentrations over Asia play a key role in modulating the Indian summer monsoon (ISM) rainfall. Lockdown measures imposed to prevent the spread of the COVID-19 pandemic led to substantial reductions in observed Asian aerosol loadings. Here, we use bottom-up estimates of anthropogenic emissions based on national mobility data from Google and Apple, along with simulations from the ECHAM6-HAMMOZ state-of-the-art aerosol-chemistry-climate model to investigate the impact of the reduced aerosol and gases pollution loadings on the ISM. We show that the decrease in anthropogenic emissions led to a 4 W m −2 increase in surface solar radiation over parts of South Asia, which resulted in a strengthening of the ISM. Simultaneously, while natural emission parameterizations are kept the same in all our simulations, the anthropogenic emission reduction led to changes in the atmospheric circulation, causing accumulation of dust over the Tibetan plateau (TP) during the pre-monsoon and monsoon seasons. This accumulated dust has intensified the warm core over the TP that reinforced the intensification of the Hadley circulation. The associated cross-equatorial moisture influx over the Indian landmass led to an enhanced amount of rainfall by 4% (0.2 mm d −1 ) over the Indian landmass and 5%–15% (0.8–3 mm d −1 ) over central India. These estimates may vary under the influence of large-scale coupled atmosphere–ocean oscillations (e.g. El Nino Southern Oscillation, Indian Ocean Dipole). Our study indicates that the reduced anthropogenic emissions caused by the unprecedented COVID-19 restrictions had a favourable effect on the hydrological cycle over South Asia, which has been facing water scarcity during the past decades. This emphasizes the need for stringent measures to limit future anthropogenic emissions in South Asia for protecting one of the world’s most densely populated regions
Aerosol · Atmosphere (unit · Atmospheric sciences · Climate change · Climatology · East Asian Monsoon · General Circulation Model · Geography · Hadley cell · Indian Ocean Dipole · Meteorology · Monsoon · Monsoon of South Asia · Plateau (mathematics · Sea surface temperature · South asia · Atmospheric aerosols and clouds · Atmospheric chemistry and aerosols · COVID-19 impact on air quality · Environmental Science · Geology · Oceanography
| Unique citing works | 2 |
|---|---|
| Citations per year | 2 |
| Citation span | 2025 - 2025 (1) |
| Citation velocity | recent |
| Highly cited | No |
| Citation types | Neutral: 2 |