摘要：The authors examine the equilibrium climatic response to the direct radiative effect (DRE) of mineral dust and sea salt aerosols in a doubled-CO2 climate with two-way coupling of aerosol-climate interactions. In response to the drier and windier conditions, dust emissions increase by 26% in the Sahara Desert and by 18% on the global scale relative to present day. Sea salt emissions increase in high latitudes (>60°) but decrease in middle latitudes (30°–60°) of both hemispheres due to the poleward shift of westerlies, leading to a 3% decrease in global emissions. The burdens of dust and sea salt increase by 31% and 7% respectively, because reductions in rainfall over the tropical oceans increase the lifetime of particles in the warmer climate. The higher aerosol loading in the doubled-CO2 climate reinforces aerosol DRE by .0.2 W m.-2, leading to an additional cooling of 0.1° at the surface compared with the climatic effects of aerosols in present day. The additional cooling from changes in natural aerosols compensates for up to 15% of the regional warming induced by doubled CO2.
关键词：mineral dust; sea salt aerosol; direct radiative effect
