Is Arctic Amplification Dominated by Regional Radiative Forcing and Feedbacks: Perspectives From the World‐Avoided Scenario

Abstract

AbstractArctic amplification (AA) is typically associated with Planck, lapse rate, and ice albedo feedbacks. However, the relative importance of poleward energy transport on AA remains uncertain. Here, we analyze integrations from a Chemistry Climate Model to investigate the impact of the Montreal Protocol on forcing, feedback, and transport contributions to AA. Two ensembles of future integrations are considered—one projecting decreasing ozone‐depleting substance concentrations and stratospheric ozone recovery and another assuming that ozone‐depleting substances are not regulated (the “World Avoided”). We find similar degrees of AA in both ensembles, despite a negative radiative forcing over the Arctic in the “World Avoided” from massive ozone loss. That negative radiative forcing is primarily balanced from positive atmospheric energy flux convergence and long‐wave cloud feedbacks. Our results highlight the impact of inhomogeneous radiative forcing on regional differences in forcing and feedback strength and the importance of radiative forcing meridional structure on poleward energy transport.