Evaluating Cloud Feedback Components in Observations and Their Representation in Climate Models

Abstract

This study quantifies the contribution of individual cloud feedbacks to the total short‐term cloud feedback in satellite observations over the period 2002–2014 and evaluates how they are represented in climate models. The observed positive total cloud feedback is primarily due to positive high‐cloud altitude, extratropical high‐ and low‐cloud optical depth, and land cloud amount feedbacks partially offset by negative tropical marine low‐cloud feedback. Seventeen models from the Atmosphere Model Intercomparison Project of the sixth Coupled Model Intercomparison Project are analyzed. The models generally reproduce the observed moderate positive short‐term cloud feedback. However, compared to satellite estimates, the models are systematically high‐biased in tropical marine low‐cloud and land cloud amount feedbacks and systematically low‐biased in high‐cloud altitude and extratropical high‐ and low‐cloud optical depth feedbacks. Errors in modeled short‐term cloud feedback components identified in this analysis highlight the need for improvements in model simulations of the response of high clouds and tropical marine low clouds. Our results suggest that skill in simulating interannual cloud feedback components may not indicate skill in simulating long‐term cloud feedback components.

Factors determining tropical upper-level cloud radiative effect in the radiative-convective equilibrium framework

“…In other words, by excluding interactions with the ocean, we could focus more closely on analyzing the contributions of clouds and atmospheric variables when determining the factors influencing TUCRE. However, the variability of TUC feedback estimated over longer terms may differ from those estimated over shorter terms (such as monthly data) as in this study 32 . Therefore, we suggest further research to consider such aspects in understanding TUCRE and the factors determining it.…”

Contributions From Cloud Morphological Changes to the Interannual Shortwave Cloud Feedback Based on MODIS and ISCCP Satellite Observations

“…In particular, these satellite-based decomposition of cloud feedbacks can be used to evaluate the ability of GCMs to simulate the interannual cloud feedback if compared in an equivalent fashion, that is, using the relevant satellite simulator, the same time period, and the same analysis methods. Direct comparisons between GCMs and satellite observations can reveal shortcomings in the representation of certain cloud regimes (Chao et al, 2024). It is therefore important that modeling centers continue to or begin to adopt satellite simulators in their simulations and make their output publicly accessible.…”

“…The results presented herein are relevant to both approaches of constraining the cloud feedback: we apply satellite remote sensing observations directly to infer the interannual cloud feedback using a novel technique as a step toward indirectly improving GCMs at the process level. Although the interannual cloud feedback inferred from the novel technique employed here relates to short timescale processes that may not necessarily correspond to the long-term cloud feedback inferred from GCMs (Chao et al, 2024), many of the cloud processes that cause uncertainties in the long-term cloud feedback are observable short-term responses. Indeed, it has been shown that interannual and long-term cloud feedbacks are well-correlated across GCMs (Zhou et al, 2016).…”