Direct radiative effect by multicomponent aerosol over China

Journal Article · Fri May 01 00:00:00 EDT 2015 · Journal of Climate

DOI:https://doi.org/10.1175/JCLI-D-14-00365.1· OSTI ID:1225142

Huang, Xin; Song, Yu; Zhao, Chun; Cai, Xuhui; Zhang, Hongsheng; Zhu, Tong

The direct radiative effect (DRE) of multiple aerosol species (sulfate, nitrate, ammonium, black carbon (BC), organic carbon (OC), and mineral aerosol) and their spatiotemporal variations over China were investigated using a fully coupled meteorology–chemistry model (WRF-Chem) for the entire year of 2006. We made modifications to improve model performance, including updating land surface parameters, improving the calculation of transition metal-catalyzed oxidation of SO₂, and adding in heterogeneous reactions between mineral aerosol and acid gases. The modified model well reproduced the magnitude, seasonal pattern, and spatial distribution of the measured meteorological conditions, concentrations of PM₁₀ and its components, and aerosol optical depth (AOD). A diagnostic iteration method was used to estimate the overall DRE of aerosols and contributions from different components. At the land surface, all kinds of aerosol species reduced the incident net radiation flux with a total DRE of 10.2 W m^-2 over China. Aerosols significantly warm the atmosphere with the national mean DRE of +10.8 W m^-2. BC was the leading radiative-heating component (+8.7 W m^-2), followed by mineral aerosol (+1.1 W m^-2). At the top of the atmosphere (TOA), BC introduced the largest radiative perturbation (+4.5 W m^-2), followed by sulfate (-1.4 W m^-2). The overall perturbation of aerosols on radiation transfer is quite small over China, demonstrating the counterbalancing effect between scattering and adsorbing aerosols. Aerosol DRE at the TOA had distinct seasonality, generally with a summer maximum and winter minimum, mainly determined by mass loadings, hygroscopic growth, and incident radiation flux.

• Research Organization: Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1225142
• Report Number(s): PNNL-SA-108376; KP1703010
• Journal Information: Journal of Climate, Vol. 28, Issue 9; ISSN 0894-8755
• Publisher: American Meteorological Society
• Country of Publication: United States
• Language: English