Instantaneous heating rate forcing differentiates tropical high-cloud adjustments across greenhouse gases.

Instantaneous radiative forcing from greenhouse gases causes divergent tropical high-cloud responses, with CO2 increasing and CH4 and N2O decreasing cloud cover.

• Why it matters: Understanding how different GHGs influence tropical high clouds is crucial because these clouds regulate large-scale circulation and the hydrological cycle, yet their rapid adjustments are not well understood.
• What they did: Using a model hierarchy with fixed sea surface temperature, the study examined the effects of CO2, CH4, and N2O on high-cloud cover, focusing on changes in vertical radiative heating structure.
• The result: Findings show that the vertical structure of radiative forcing primarily drives cloud adjustments, emphasizing the need to consider radiative heating profiles beyond traditional top-of-atmosphere metrics for climate predictions.