Climate Response to Radiative Forcing By (Dust) Aerosols: Energy and Moisture Constraints

The radiative perturbation to climate by aerosols has large regional variations, reflecting the localized sources and short lifetime of aerosols compared to greenhouse gases like carbon dioxide. The climate adjusts to aerosol forcing far beyond regions of high concentration through atmospheric transport of energy and moisture. This combination of local sources and planetary scale adjustment makes it challenging to identify the robust climate response to aerosols that is consistent among different climate models and is expected to appear in future model simulations. Constraints from the atmospheric budgets of energy and moisture help to identify robust aspects of both the global and regional climate response. We will illustrate some of these constraints for the example of dust aerosols that are created by soil erosion and make a leading contribution to the emitted aerosol mass.