Schulz et al. (2026) The Response of Tropical Land–Ocean Precipitation Partitioning to SST and CO2 Increase in Global Storm-Resolving Simulations

Identification

• Journal: Journal of Climate
• Year: 2026
• Date: 2026-08-26
• Authors: Marius Schulz, Cathy Hohenegger
• DOI: 10.1175/jcli-d-26-0041.1

Research Groups

• Max Planck Institute for Meteorology (Hamburg, Germany)
• International Max Planck Research School on Earth System Modelling (Hamburg, Germany)

Short Summary

This study investigates how tropical land-ocean precipitation partitioning responds to idealized forcing, including CO2 increase and uniform sea surface temperature increase. The research uses the icosahedral nonhydrostatic (ICON) model, a global storm-resolving model that explicitly simulates convection.

Objective

• Investigate the response of tropical land-ocean precipitation partitioning to CO2 increase and uniform sea surface temperature increase.
• Compare the results from the ICON model with those from coarser models that parameterize convection.

Study Configuration

• Spatial Scale: Global, with a horizontal grid spacing of 10 km.
• Temporal Scale: 14-year simulations.

Methodology and Data

• Models used: The icosahedral nonhydrostatic (ICON) model.
• Data sources: Atmospheric-only simulations, using external datasets for boundary conditions.

Main Results

• Precipitation partitioning in ICON shows better agreement with observations than the AMIP6 ensemble.
• Under 4×CO2, precipitation partitioning increases, favoring land precipitation.
• Upon +4-K sea surface temperatures (SSTs), precipitation partitioning decreases.
• The response of tropical precipitation partitioning is decomposed into contributions from land atmospheric heating, land circulation efficiency, land moisture cycling, and tropical radiative cooling.

Contributions

• This study provides new insights into the response of tropical land-ocean precipitation partitioning to idealized forcing.
• The results suggest that traditional climate models using convective parameterizations might underestimate the landward shift of precipitation in response to CO2 forcing.

Funding

• Not specified.

Citation

@article{Schulz2026Response,
  author = {Schulz, Marius and Hohenegger, Cathy},
  title = {The Response of Tropical Land–Ocean Precipitation Partitioning to SST and CO2 Increase in Global Storm-Resolving Simulations},
  journal = {Journal of Climate},
  year = {2026},
  doi = {10.1175/jcli-d-26-0041.1},
  url = {https://doi.org/10.1175/jcli-d-26-0041.1}
}