Atmospheric and Oceanic Responses to the Redistribution of Anthropogenic Aerosols

With a quasi-exponential growth in industrialization since the mid-1990s, Asia has undergone a dramatic increase in anthropogenic emissions of aerosol and precursor gases to the atmosphere. Meanwhile, such emissions have been stabilized or reduced over North America and Europe. Our recent paper based on a suite of NCAR CAM5 simulations suggests that the altered cloud reflectivity and solar extinction by aerosols results in regional surface temperature cooling in East and South Asia, and warming in US and Europe respectively. Moreover, the reduced meridional streamfunctions and zonal winds over the tropics as well as a poleward shift of the jet stream suggest weakened and expanded tropical circulations, which are induced by the redistributed aerosols through a relaxing of the meridional temperature gradient. We further employ the CAM5 coupled with a slab ocean model to investigate feedbacks from interactive sea surface temperatures on the simulated atmospheric responses to the redistribution of anthropogenic aerosols. The simulations from the comprehensive atmosphere-ocean fully coupled NCAR CESM will be also presented to systematically examine the transient and equilibrium response of the whole earth system to the shifted anthropogenic emissions and the redistributed aerosols.