Impact of anthropogenic aerosols on Indian summer monsoon

Journal Article · Thu Nov 05 04:00:00 EST 2009 · Geophysical Research Letters, 36:Article No. L21704

DOI:https://doi.org/10.1029/2009GL040114· OSTI ID:1008260

Wang, Chien; Kim, Dongchul; Ekman, Annica; Barth, Mary; Rasch, Philip J

Using an interactive aerosol-climate model we find that absorbing anthropogenic aerosols, whether coexisting with scattering aerosols or not, can significantly affect the Indian summer monsoon system. We also show that the influence is reflected in a perturbation to the moist static energy in the sub-cloud layer, initiated as a heating by absorbing aerosols to the planetary boundary layer. The perturbation appears mostly over land, extending from just north of the Arabian Sea to northern India along the southern slope of the Tibetan Plateau. As a result, during the summer monsoon season, modeled convective precipitation experiences a clear northward shift, coincidently in agreement with observed monsoon precipitation changes in recent decades particularly during the onset season. We demonstrate that the sub-cloud layer moist static energy is a useful quantity for determining the impact of aerosols on the northward extent and to a certain degree the strength of monsoon convection.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1008260
• Report Number(s): PNNL-SA-69986
• Journal Information: Geophysical Research Letters, 36:Article No. L21704, Journal Name: Geophysical Research Letters, 36:Article No. L21704 Vol. 36; ISSN GPRLAJ; ISSN 0094-8276
• Country of Publication: United States
• Language: English

Related Subjects

58 GEOSCIENCES
AEROSOLS
ARABIAN SEA
BOUNDARY LAYERS
CONVECTION
HEATING
INDIA
MONSOONS
PRECIPITATION
SCATTERING