What type of study is this?

This is a Observational study (also classified as: Analysis of model outputs).

September 5, 2025Open Access

Responses to Lower‐Tropospheric Stability Dominate Intermodel Differences in the Historical Pattern Effect

Key Points

Low cloud feedback variations are significantly influenced by lower tropospheric stability (LTS) and sea surface temperature (SST).
Using data from 16 climate models (CMIP5 and CMIP6), the study highlights the dominant role of LTS in cloud feedback variation.
Cloud controlling factor analysis indicates that existing models underestimate the sensitivity of low clouds to changes in LTS and SST.
Understanding these variations in feedback could improve projections of climate change impacts based on historical SST patterns.

Abstract

Abstract The sea surface temperature (SST) pattern modulates the Earth's radiative feedbacks at decadal timescales. However, decadal feedback variations over the historical period depend on the choice of climate model, even when forced with the same SST data set. We investigate these differences through analyzing amip‐piForcing output, focusing on low cloud feedback. Time‐variation in low cloud feedback results primarily from the SST pattern, mediated by changes in near‐global lower tropospheric stability (LTS). We investigate the meteorological factors contributing to low cloud feedback variation through the cloud controlling factor analysis method, diagnosing cloud radiative sensitivities from 16 CMIP5 and CMIP6 models, and an observational constraint from MODIS. We find the radiative sensitivity of models to LTS in the stratocumulus regions dominates the magnitude of cloud feedback time variation due to the pattern effect. Additionally, models underestimate low cloud radiative sensitivity to changes in LTS and SST and thus the time‐variation in feedback.

Read Full Paperexternally

Mark Helpful

Bookmark

Relay

View Full Paper