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Title: Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability

Authors:
; ; ; ; ; ; ; ; ; ; ; ; ; ;
Publication Date:
Sponsoring Org.:
USDOE
OSTI Identifier:
1239694
Grant/Contract Number:
KP1703010
Resource Type:
Journal Article: Published Article
Journal Name:
Proceedings of the National Academy of Sciences of the United States of America
Additional Journal Information:
Journal Volume: 113; Journal Issue: 21; Related Information: CHORUS Timestamp: 2017-06-24 03:05:56; Journal ID: ISSN 0027-8424
Publisher:
Proceedings of the National Academy of Sciences
Country of Publication:
United States
Language:
English

Citation Formats

Ghan, Steven, Wang, Minghuai, Zhang, Shipeng, Ferrachat, Sylvaine, Gettelman, Andrew, Griesfeller, Jan, Kipling, Zak, Lohmann, Ulrike, Morrison, Hugh, Neubauer, David, Partridge, Daniel G., Stier, Philip, Takemura, Toshihiko, Wang, Hailong, and Zhang, Kai. Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability. United States: N. p., 2016. Web. doi:10.1073/pnas.1514036113.
Ghan, Steven, Wang, Minghuai, Zhang, Shipeng, Ferrachat, Sylvaine, Gettelman, Andrew, Griesfeller, Jan, Kipling, Zak, Lohmann, Ulrike, Morrison, Hugh, Neubauer, David, Partridge, Daniel G., Stier, Philip, Takemura, Toshihiko, Wang, Hailong, & Zhang, Kai. Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability. United States. doi:10.1073/pnas.1514036113.
Ghan, Steven, Wang, Minghuai, Zhang, Shipeng, Ferrachat, Sylvaine, Gettelman, Andrew, Griesfeller, Jan, Kipling, Zak, Lohmann, Ulrike, Morrison, Hugh, Neubauer, David, Partridge, Daniel G., Stier, Philip, Takemura, Toshihiko, Wang, Hailong, and Zhang, Kai. 2016. "Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability". United States. doi:10.1073/pnas.1514036113.
@article{osti_1239694,
title = {Challenges in constraining anthropogenic aerosol effects on cloud radiative forcing using present-day spatiotemporal variability},
author = {Ghan, Steven and Wang, Minghuai and Zhang, Shipeng and Ferrachat, Sylvaine and Gettelman, Andrew and Griesfeller, Jan and Kipling, Zak and Lohmann, Ulrike and Morrison, Hugh and Neubauer, David and Partridge, Daniel G. and Stier, Philip and Takemura, Toshihiko and Wang, Hailong and Zhang, Kai},
abstractNote = {},
doi = {10.1073/pnas.1514036113},
journal = {Proceedings of the National Academy of Sciences of the United States of America},
number = 21,
volume = 113,
place = {United States},
year = 2016,
month = 2
}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1073/pnas.1514036113

Citation Metrics:
Cited by: 22works
Citation information provided by
Web of Science

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  • This manuscript will be submitted to Atmospheric Chemistry and Physics. The manuscript file is attached to this Erica.
  • We present a series of regional climate model simulations aimed at assessing the radiative forcing and surface climatic effects of anthropogenic sulfate and fossil fuel soot over east Asia. The simulations are carried out with a coupled regional climate-chemistry/aerosol model for the 5-year period of 1993-1997 using published estimates of sulfur emissions for the period. Anthropogenic sulfate induces a negative radiative forcing spatially varying from -1 to -8 W/m2 in the winter to -1 to -15 W/m2 in the summer, with maxima over the Sichan Basin of southwest China and over some areas of east and northeast China. This forcingmore » induces a surface cooling in the range of -0.1 to -0.7 K. Fossil fuel soot exerts a positive atmospheric radiative forcing of 0.5 to 2 W/m2 and enhances the surface cooling by a few tenths of K due to increased surface shielding from solar radiation. Doubling of sulfur emissions induces a substantial increase in radiative forcing (up to -7 to -8 W/m2) and associated surface cooling. With doubled sulfur emissions, the surface cooling exceeds -1 K and is statistically significant at the 90% confidence level over various areas of China. The aerosol forcing and surface cooling tend to inhibit precipitation over the region, although this effect is relatively small in the simulations. Some features of the simulated aerosol-induced cooling are consistent with temperature trends observed in recent decades over different regions of China.« less
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  • A high-resolution estimate of monthly 3D aerosol solar heating rates and surface solar fluxes in Asia from 2001 to 2004 is described here. This product stems from an Asian aerosol assimilation project, in which a) the PNNL regional model bounded by the NCEP reanalyses was used to provide meteorology, b) MODIS and AERONET data were integrated for aerosol observations, c) the Iowa aerosol/chemistry model STEM-2K1 used the PNNL meteorology and assimilated aerosol observations, and d) 3D (X-Y-Z) aerosol simulations from the STEM-2K1 were used in the Scripps Monte-Carlo Aerosol Cloud Radiation (MACR) model to produce total and anthropogenic aerosol directmore » solar forcing for average cloudy skies. The MACR model and STEM both used the PNNL model resolution of 0.45º×0.4º in the horizontal and of 23 layers in the troposphere. The 2001–2004 averaged anthropogenic all-sky aerosol forcing is -1.3 Wm -2 (TOA), +7.3 Wm -2 (atmosphere) and -8.6 Wm -2 (surface) averaged in Asia (60-138°E & Eq. -45°N). In the absence of AERONET SSA assimilation, absorbing aerosol concentration (especially BC aerosol) is much smaller, giving -2.3 Wm -2 (TOA), +4.5 Wm -2 (atmosphere) and -6.8 Wm -2 (surface), averaged in Asia. In the vertical, monthly forcing is mainly concentrated below 600hPa with maxima around 800hPa. Seasonally, low-level forcing is far larger in dry season than in wet season in South Asia, whereas the wet season forcing exceeds the dry season forcing in East Asia. The anthropogenic forcing in the present study is similar to that in Chung et al.’s [2005] in overall magnitude but the former offers fine-scale features and simulated vertical profiles. The interannual variability of the computed anthropogenic forcing is significant and extremely large over major emission outflow areas. In view of this, the present study’s estimate is within the implicated range of the 1999 INDOEX result. However, NCAR/CCSM3’s anthropogenic aerosol forcing is much smaller than the present study’s estimate at the surface, and is outside of what the INDOEX findings can support.« less