Chagnaud, G., Taylor, C. M., Jackson, L. S. et al. (3 more authors) (2025) Wet-Bulb Temperature Extremes Locally Amplified by Wet Soils. Geophysical Research Letters, 52 (8). e2024GL112467. ISSN 0094-8276
Abstract
Wet-bulb temperature extremes (WTEs) occur due to a combination of high humidity and temperature, and are hazardous to human health. Alongside favourable large-scale conditions, surface fluxes play an important role in WTEs; yet, little is known about how land surface heterogeneity influences them. Using a 10-year, pan-African convection-permitting model simulation, we find that most WTEs have spatial extents 2,000 . They occur preferentially over positive soil moisture anomalies (SMA) typically following rainfall. The wet-bulb temperature is locally amplified by 0.5–0.6 C in events associated with smaller-scale SMA (50 km across) compared to events with larger-scale SMA (300 km across). A mesoscale cifrculation, resulting from stronger spatial contrasts of sensible heat flux, more efficiently concentrates moist, warm air in a shallower boundary layer. This mechanism could explain the underestimation of peak Twb values in coarser-resolution products. The role of antecedent SMA from recent rainfall may help issue localized early warnings.
Metadata
Item Type: | Article |
---|---|
Authors/Creators: |
|
Copyright, Publisher and Additional Information: | © 2025. The Author(s). This is an open access article under the terms of the Creative Commons Attribution License (CC-BY 4.0), which permits unrestricted use, distribution and reproduction in any medium, provided the original work is properly cited. |
Keywords: | humid heat extremes, soil moisture, thermally-induced mesoscale circulation, land-atmosphere coupling, convection-permitting modelling, tropics |
Dates: |
|
Institution: | The University of Leeds |
Academic Units: | The University of Leeds > Faculty of Environment (Leeds) > School of Earth and Environment (Leeds) |
Funding Information: | Funder Grant number NERC (Natural Environment Research Council) NE/X013618/1 |
Depositing User: | Symplectic Publications |
Date Deposited: | 02 Apr 2025 08:30 |
Last Modified: | 30 May 2025 14:00 |
Status: | Published |
Publisher: | Wiley |
Identification Number: | 10.1029/2024GL112467 |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:225056 |