Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset

The direct radiative effect of absorbing aerosols consists of absorption-induced atmospheric heating together with scattering- and absorption-induced surface cooling. It is thus important to understand whether some of the reported climate impacts of anthropogenic absorbing aerosols are mainly due to...

Full description

Bibliographic Details
Main Authors: Lee, Shao-Yi, Shin, Ho-Jeong, Wang, Chien
Other Authors: Massachusetts Institute of Technology. Center for Global Change Science
Format: Article
Language:en_US
Published: American Meteorological Society 2014
Online Access:http://hdl.handle.net/1721.1/87783
https://orcid.org/0000-0002-3979-4747
_version_ 1811098085801066496
author Lee, Shao-Yi
Shin, Ho-Jeong
Wang, Chien
author2 Massachusetts Institute of Technology. Center for Global Change Science
author_facet Massachusetts Institute of Technology. Center for Global Change Science
Lee, Shao-Yi
Shin, Ho-Jeong
Wang, Chien
author_sort Lee, Shao-Yi
collection MIT
description The direct radiative effect of absorbing aerosols consists of absorption-induced atmospheric heating together with scattering- and absorption-induced surface cooling. It is thus important to understand whether some of the reported climate impacts of anthropogenic absorbing aerosols are mainly due to the coexistence of these two opposite effects and to what extent the nonlinearity raised from such coexistence would become a critical factor. To answer these questions specifically regarding the South Asia summer monsoon with focus on aerosol-induced changes in monsoon onset, a set of century-long simulations using the Community Earth System Model, version 1.0.3 (CESM 1.0.3), of NCAR with fully coupled atmosphere and ocean components was conducted. Prescribed direct heating to the atmosphere and cooling to the surface were applied in the simulations over the Indian subcontinent, either alone or combined, during the aerosol-laden months of May and June. Over many places in the Indian subcontinent, the nonlinear effect dominates in the changes of subcloud layer moist static energy, precipitation, and monsoon onset. The surface cooling effect of aerosols appears to shift anomalous precipitative cooling away from the aerosol-forcing region and hence turn the negative feedback to aerosol-induced atmospheric heating into a positive feedback on the monsoon circulation through latent heat release over the Himalayan foothills. Moisture processes form the critical chain mediating local aerosol direct effects and onset changes in the monsoon system.
first_indexed 2024-09-23T17:09:41Z
format Article
id mit-1721.1/87783
institution Massachusetts Institute of Technology
language en_US
last_indexed 2024-09-23T17:09:41Z
publishDate 2014
publisher American Meteorological Society
record_format dspace
spelling mit-1721.1/877832022-10-03T10:49:24Z Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset Lee, Shao-Yi Shin, Ho-Jeong Wang, Chien Massachusetts Institute of Technology. Center for Global Change Science Shin, Ho-Jeong Wang, Chien The direct radiative effect of absorbing aerosols consists of absorption-induced atmospheric heating together with scattering- and absorption-induced surface cooling. It is thus important to understand whether some of the reported climate impacts of anthropogenic absorbing aerosols are mainly due to the coexistence of these two opposite effects and to what extent the nonlinearity raised from such coexistence would become a critical factor. To answer these questions specifically regarding the South Asia summer monsoon with focus on aerosol-induced changes in monsoon onset, a set of century-long simulations using the Community Earth System Model, version 1.0.3 (CESM 1.0.3), of NCAR with fully coupled atmosphere and ocean components was conducted. Prescribed direct heating to the atmosphere and cooling to the surface were applied in the simulations over the Indian subcontinent, either alone or combined, during the aerosol-laden months of May and June. Over many places in the Indian subcontinent, the nonlinear effect dominates in the changes of subcloud layer moist static energy, precipitation, and monsoon onset. The surface cooling effect of aerosols appears to shift anomalous precipitative cooling away from the aerosol-forcing region and hence turn the negative feedback to aerosol-induced atmospheric heating into a positive feedback on the monsoon circulation through latent heat release over the Himalayan foothills. Moisture processes form the critical chain mediating local aerosol direct effects and onset changes in the monsoon system. National Science Foundation (U.S.) (AGS-0944121) United States. Environmental Protection Agency (XA-83600001-0) 2014-06-13T18:34:57Z 2014-06-13T18:34:57Z 2013-08 2013-01 Article http://purl.org/eprint/type/JournalArticle 0894-8755 1520-0442 http://hdl.handle.net/1721.1/87783 Lee, Shao-Yi, Ho-Jeong Shin, and Chien Wang. “Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset.” J. Climate 26, no. 15 (August 2013): 5594–5607. © 2013 American Meteorological Society https://orcid.org/0000-0002-3979-4747 en_US http://dx.doi.org/10.1175/jcli-d-12-00741.1 Journal of Climate Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. application/pdf American Meteorological Society American Meteorological Society
spellingShingle Lee, Shao-Yi
Shin, Ho-Jeong
Wang, Chien
Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title_full Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title_fullStr Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title_full_unstemmed Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title_short Nonlinear Effects of Coexisting Surface and Atmospheric Forcing of Anthropogenic Absorbing Aerosols: Impact on the South Asian Monsoon Onset
title_sort nonlinear effects of coexisting surface and atmospheric forcing of anthropogenic absorbing aerosols impact on the south asian monsoon onset
url http://hdl.handle.net/1721.1/87783
https://orcid.org/0000-0002-3979-4747
work_keys_str_mv AT leeshaoyi nonlineareffectsofcoexistingsurfaceandatmosphericforcingofanthropogenicabsorbingaerosolsimpactonthesouthasianmonsoononset
AT shinhojeong nonlineareffectsofcoexistingsurfaceandatmosphericforcingofanthropogenicabsorbingaerosolsimpactonthesouthasianmonsoononset
AT wangchien nonlineareffectsofcoexistingsurfaceandatmosphericforcingofanthropogenicabsorbingaerosolsimpactonthesouthasianmonsoononset