A numerical study of the effect of different aerosol types on East Asian summer clouds and precipitation

Journal Article · Wed May 01 04:00:00 EDT 2013 · Atmospheric Environment, 70:51-63

DOI:https://doi.org/10.1016/j.atmosenv.2012.12.039· OSTI ID:1072855

Jiang, Yiquan; Liu, Xiaohong; Yang, Xiuqun; Wang, Minghuai

The impact of anthropogenic aerosol on the East Asian summer monsoon (EASM) is investigated with NCAR CAM5, a state-of-the-art climate model with aerosol’s direct and indirect effects. Results indicate that anthropogenic aerosol tends to cause a weakened EASM with a southward shift of precipitation in East Asia mostly by its radiative effect. Anthropogenic aerosol induced surface cooling stabilizes the boundary layer, suppresses the convection and latent heat release in northern China, and reduces the tropospheric temperature over land and land-sea thermal contrast, thus leading to a weakened EASM. Meanwhile, acting as cloud condensation nuclei (CCN), anthropogenic aerosol can significantly increase the cloud droplet number concentration but decrease the cloud droplet effective radius over Indochina and Indian Peninsulas as well as over southwestern and northern China, inhibiting the precipitation in these regions. Thus, anthropogenic aerosol tends to reduce Southeast and South Asian summer monsoon precipitation by its indirect effect.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1072855
• Report Number(s): PNNL-SA-79486; KP1703020
• Journal Information: Atmospheric Environment, 70:51-63, Journal Name: Atmospheric Environment, 70:51-63
• Country of Publication: United States
• Language: English