Soil organic matter reduces persistent nighttime surface warm bias in convection-permitting U.S. simulations
Lin, T., He, C., Liu, C., Abolafia-Rosenzweig, R., Dudhia, J., et al. (2026). Soil organic matter reduces persistent nighttime surface warm bias in convection-permitting U.S. simulations. Geophysical Research Letters, doi:https://doi.org/10.1029/2026gl123274
| Title | Soil organic matter reduces persistent nighttime surface warm bias in convection-permitting U.S. simulations |
|---|---|
| Genre | Article |
| Author(s) | Tzu-Shun Lin, Cenlin He, Changhai Liu, Ronnie Abolafia-Rosenzweig, Jimy Dudhia, M. Barlage, Zhe Zhang, Andrew J. Newman |
| Abstract | Convection-permitting modeling has become a cornerstone for improving representation of land-atmosphere processes, predicting weather extremes, and creating long-term hydrometeorological data sets. The convection-permitting Weather Research and Forecasting (WRF) modeling with the NoahMP land-surface scheme is widely used for kilometer-scale hydroclimatic applications. We identify persistent large warm biases (up to ∼8°C) in daily minimum surface air temperature (Tmin) in convection-permitting WRF/NoahMP simulations across the western, central, and southeastern US. Motivated by the potential of soil organic matter (SOM) to mitigate nighttime warm bias, we implement a physical representation of this previously missing component and assess its effects on land-surface fluxes and surface air temperature. Including SOM significantly changes surface soil thermal properties and reduces Tmin warm bias (by 75%) by mitigating the overestimated diurnal amplitude of ground heat flux (by 29%). This offers a physics-based pathway to improve future kilometer-scale simulations. |
| Publication Title | Geophysical Research Letters |
| Publication Date | Jun 16, 2026 |
| Publisher's Version of Record | https://doi.org/10.1029/2026gl123274 |
| OpenSky Citable URL | https://n2t.net/ark:/85065/d70c51bq |
| OpenSky Listing | View on OpenSky |
| RAL Affiliations | HAP, WCAP |