Shaw et al. (2025) Moist Adiabatic Scaling Explains Mean and Fast Upper‐Level Jet Stream Wind Response to Climate Change

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Geophysical Research Letters
• Year: 2025
• Date: 2025-10-26
• Authors: Tiffany A. Shaw, Osamu Miyawaki
• DOI: 10.1029/2025gl118315

Research Groups

Not specified in the abstract.

Short Summary

This paper derives a moist adiabatic scaling that explains the observed increase in upper-level jet stream strength and shear under climate change, demonstrating that the response is primarily driven by the increase in surface moisture gradient following the Clausius-Clapeyron relation.

Objective

• To derive a moist adiabatic scaling that explains the upper-level jet stream wind response to climate change.

Study Configuration

• Spatial Scale: Global/Hemispheric (upper-level atmosphere, focusing on jet streams).
• Temporal Scale: Climate change (decadal to centennial trends), with daily surface air temperature distribution as input for the scaling.

Methodology and Data

• Models used: A climate model hierarchy (specific models not named) was used to test the derived scaling.
• Data sources: Not explicitly stated, but the scaling uses daily surface air temperature distribution as input.

Main Results

• A moist adiabatic scaling was derived that explains the upper-level jet stream wind response to climate change.
• Across a climate model hierarchy, the scaling predicts an increase of 2% per kelvin (K) for the upper-level mean and fast jet stream wind, and an increase of 4% per kelvin (K) for the jet stream shear.
• The increase in the surface moisture gradient, following the Clausius-Clapeyron relation, is shown to dominate the jet stream's response.
• The scaling connects the increasing surface moisture gradient to the upper-level temperature gradient, thereby reconciling dry and moist perspectives on jet stream changes.
• Record-breaking upper-level jet stream winds and increased clear-air turbulence are robust and well-understood consequences of climate change, directly tied to the Clausius-Clapeyron relation.

Contributions

• Derivation of a novel moist adiabatic scaling that quantitatively explains the upper-level jet stream's response to climate change.
• Identification of the surface moisture gradient, governed by the Clausius-Clapeyron relation, as the dominant factor driving jet stream strengthening and shear increase.
• Reconciliation of previously distinct dry and moist perspectives on jet stream dynamics by linking surface moisture gradients to upper-level temperature gradients.
• Reinforcement of the robustness and predictability of future changes in jet stream characteristics and associated phenomena like clear-air turbulence under climate change.

Funding

Not specified in the abstract.

Citation

@article{Shaw2025Moist,
  author = {Shaw, Tiffany A. and Miyawaki, Osamu},
  title = {Moist Adiabatic Scaling Explains Mean and Fast Upper‐Level Jet Stream Wind Response to Climate Change},
  journal = {Geophysical Research Letters},
  year = {2025},
  doi = {10.1029/2025gl118315},
  url = {https://doi.org/10.1029/2025gl118315}
}