Diurnal Variability Modulates Episodic Convection in Hothouse Climates Over Ocean and Swamp‐Like Surface Conditions

Journal article

Plain Language Summary: In hot and wet “hothouse” climate conditions, rainfall transitions from a pattern that fluctuates from about a mean of 3 mm day − 1 ${\text{day}}^{-1}$ to more intense outbursts that are separated by multi‐day dry spells. Previous studies on hothouse climates did not consider the role of the diurnal cycle even though it strongly controls precipitation in Earth's current climate. This study uses radiative‐convective equilibrium simulations to investigate the impact of rising temperatures on the transition to hothouse conditions, incorporating the diurnal cycle with both swamp‐like and open ocean surface conditions. We find that episodic precipitation occurs at surface temperatures above 322 K even when accounting for the diurnal cycle. However, the diurnal cycle significantly influences the timing of convection and rainfall at high temperatures with precipitation primarily starting late at night or in the early morning.

Authors: Habib, N; Dagan, G; Steiger, N

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: Wiley
• Journal: Journal of Advances in Modeling Earth Systems
• Volume: 18
• Issue: 2
• Article number: e2025MS004992
• Publication date: 2026-02-20
• Acceptance date: 2026-01-29
• DOI: 10.1029/2025ms004992
• EISSN: 1942-2466
• ISSN: 1942-2466
• Language: English
• Keywords: diurnal; hothouse; precipitation; RCE; convection; climate