GFI/BCCR Seminar: The Role of Aerosol and Greenhouse Gas Forcing in CMIP5 Models: Impacts on Asian Monsoon and Atlantic Hurricane Intensity

Mingfang Ting (Lamont Doherty Earth Observatory, Columbia University, USA)

The Role of Aerosol and Greenhouse Gas Forcing in CMIP5 Models: Impacts on Asian Monsoon and Atlantic Hurricane Intensity

Abstract
In this talk, I will discuss our recent work on the regional climate changes in the historical period due to both the aerosol and greenhouse gas forcing, in particular how these anthropogenic forcing may have impacted the Asian monsoon and the Atlantic hurricane intensity. While aerosols and greenhouse gases tend to produce opposite sign changes in terms of surface temperature and precipitation as previously discussed, the mechanisms by which these changes occur are not entirely symmetric between the two forcing cases. For example, aerosols tend to produce largely dynamical responses in Asian monsoon circulation changes, while greenhouse gas forcing tends to be dominated by the thermodynamic impact through changes in atmospheric moisture content. For their impact on the Atlantic hurricane intensity, aerosols are more effective in causing changes in hurricane intensity than greenhouse gases, due to differences in surface energy balances. Future changes in Asian monsoon and hurricane intensity as simulated by the CMIP5 models will also be discussed as a comparison to that during the historical period.