Sinclair (2025) A Global Climatology of Tropical Cyclone Diabatic Rossby Wave Sources and Their Extratropical Flow Response

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

Identification

• Journal: Journal of Climate
• Year: 2025
• Date: 2025-12-17
• Authors: Mark R. Sinclair
• DOI: 10.1175/jcli-d-25-0175.1

Research Groups

Not explicitly mentioned in the abstract.

Short Summary

This study establishes a 46-year global climatology of Rossby wave forcing by tropical cyclones, demonstrating that TC recurvature is not a prerequisite for downstream Rossby wave excitation and that similar forcing occurs in other ocean basins.

Objective

• To test the hypothesis that Rossby wave (RW) forcing events, characterized by strong negative potential vorticity (PV) advection, can occur outside the context of recurving western North Pacific (WNP) tropical cyclones and still trigger downstream atmospheric responses.

Study Configuration

• Spatial Scale: Global, with specific focus on the Western North Pacific (WNP) basin and other tropical cyclone basins.
• Temporal Scale: 46-year climatology, spanning from 1979 to 2024.

Methodology and Data

• Models used: Composite time series analysis; Spatial composites; Calculation of potential vorticity (PV) advection by the divergent wind component.
• Data sources: Global tropical cyclone (TC) data from the International Best Track Archive for Climate Stewardship (IBTrACS) database.

Main Results

• Strong Rossby wave (RW) forcing events associated with recurving tropical cyclones (TCs) are predominantly confined to the Western North Pacific (WNP) basin.
• Removing the recurvature requirement increased the number of cases by approximately 72% without significantly altering the downstream atmospheric response.
• Tropical cyclone recurvature is not a prerequisite for the excitation or amplification of Rossby waves.
• Other TC basins exhibited a similar, albeit smaller, downstream atmospheric response.
• For recurving TCs, spatial composites indicated that the downstream response was primarily due to the direct impact of TCs migrating into the compositing domain, rather than remote downstream Rossby wave amplification.
• For nonrecurving TCs with minimal eastward progression, spatial composites revealed an amplifying standing wave pattern downstream from the longitude of the RW forcing.

Contributions

• Provides a novel 46-year global climatology of tropical cyclone-related Rossby wave forcing episodes.
• Challenges the existing paradigm by demonstrating that tropical cyclone recurvature is not essential for triggering significant downstream atmospheric responses via Rossby wave forcing.
• Expands the understanding of Rossby wave forcing to tropical cyclones in other ocean basins, identifying similar, though less pronounced, impacts.

Funding

Not explicitly mentioned in the abstract.

Citation

@article{Sinclair2025Global,
  author = {Sinclair, Mark R.},
  title = {A Global Climatology of Tropical Cyclone Diabatic Rossby Wave Sources and Their Extratropical Flow Response},
  journal = {Journal of Climate},
  year = {2025},
  doi = {10.1175/jcli-d-25-0175.1},
  url = {https://doi.org/10.1175/jcli-d-25-0175.1}
}