Interacting components of the top-of-atmosphere energy balance affect changes in regional surface temperature

The role of interactions between components of the top-of-atmosphere (TOA) energy balance in determining regional surface temperature changes, such as polar amplification, is examined in diffusive energy balance model (EBM) simulations. These interactions have implications for the interpretation of local feedback analyses when they are applied to regional surface temperature changes. Local feedback analysis succeeds at accounting for the EBM-simulated temperature change given the changes in the radiative forcing, atmospheric energy transport, and radiative feedbacks. However, the inferences about the effect of individual components of the TOA energy balance on regional temperature changes do not account for EBM simulations in which individual components are prescribed or locked. As changes in one component of the TOA energy balance affect others, unambiguous attribution statements relating changes in regional temperature or its intermodel spread to individual terms in the TOA energy balance cannot be made.