Constraint on Net Long Term Climate Feedback to Emerge From Satellite Observed Internal Variability by Mid 2040s

Climate feedbacks are vital in shaping the extent of global warming. While directly observing climate feedbacks is hardly feasible, it is possible to establish a relationship between them and top-of-the-atmosphere flux changes in response to natural fluctuations in surface temperature. In this study, we explore this method to potentially constrain climate feedbacks in climate models using observations. Our findings reveal significant correlations for longwave and shortwave feedbacks within a period of 14 years. This allows for utilizing satellite observations and reanalysis to show that models exhibiting moderate negative longwave and moderate positive shortwave internal variability feedbacks demonstrate better consistency with observations. The emergence of the relationship for the net feedback requires a longer time, about 60 years. Continuous satellite records need to be maintained minimum until the mid-2040s before estimates of observed net internal variability feedback can be used to constrain net forced climate feedback, and thereby climate sensitivity.