摘要：Earth system models (ESMs) are key tools for providing climateprojections under different scenarios of human-induced forcing. ESMs includea large number of additional processes and feedbacks such as biogeochemicalcycles that traditional physical climate models do not consider. Yet, someprocesses such as cloud dynamics and ecosystem functional response stillhave fairly high uncertainties. In this article, we present an overview ofclimate feedbacks for Earth system components currently included instate-of-the-art ESMs and discuss the challenges to evaluate and quantifythem. Uncertainties in feedback quantification arise from theinterdependencies of biogeochemical matter fluxes and physical properties,the spatial and temporal heterogeneity of processes, and the lack oflong-term continuous observational data to constrain them. We present anoutlook for promising approaches that can help to quantify and to constrain the large number of feedbacks in ESMs in the future. The target group forthis article includes generalists with a background in natural sciences andan interest in climate change as well as experts working ininterdisciplinary climate research (researchers, lecturers, and students).This study updates and significantly expands upon the last comprehensiveoverview of climate feedbacks in ESMs, which was produced 15 years ago (NRC,2003).
