Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4443866 | Atmospheric Environment | 2006 | 12 Pages |
Abstract
Shortwave direct aerosol radiative forcing (DARF) at the surface as well as aerosol optical depth (AOD) were estimated and chemically apportioned on the basis of ground-based aerosol and radiation measurements at the Gosan super-site in Korea during the Asian Pacific Regional Aerosol Characterization Experiment (ACE-Asia) in April 2001. An aerosol optical model and a radiative transfer model (RTM) were employed to calculate the aerosol extinction coefficient and radiative flux at the surface, respectively. The calculated scattering and absorption coefficients for Dp<10 μm aerosols agreed well with measured scattering and absorption coefficients with root mean square errors (RMSEs) of 23.6 and 3.0 Mmâ1, respectively. The modeled direct and diffuse irradiances at the surface were also in good agreement with the measured direct and diffuse irradiances. In this study we found that the 17-day mean aerosol radiative forcing of â38.3 W mâ2 at the surface is attributable to mineral dust (45.7%), water-soluble components (sum of sulfate, nitrate, ammonium, and water-soluble organic carbon (WSOC)) (26.8%), and elemental carbon (EC) (26.4%). However, sea salt does not play a major role. For the cases of Asian dust and smoke episodic events on 26 April 2001, a diurnal averaged forcing of â36.2 W mâ2 was contributed by mineral dust (â18.8 W mâ2), EC (â6.7 W mâ2), and water-soluble components (â10.7 W mâ2). The results of this study suggest that water-soluble and EC components as well as a mineral dust component are responsible for a large portion of the aerosol radiative forcing at the surface in the continental outflow region of East Asia.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Atmospheric Science
Authors
Jiyoung Kim, Soon-Chang Yoon, Sang-Woo Kim, Fred Brechtel, Anne Jefferson, Ellsworth G. Dutton, Keith N. Bower, Steven Cliff, James J. Schauer,