Drivers of North American Extratropical Cyclone Variability Across Time Scales: Evidence from Earth System Models
Igbinoba, M., McCrary, R., Stuivenvolt-Allen, J., McGinnis, S. A., Tye, M.. (2026). Drivers of North American Extratropical Cyclone Variability Across Time Scales: Evidence from Earth System Models. , doi:https://doi.org/10.5065/2d2d-4695
| Title | Drivers of North American Extratropical Cyclone Variability Across Time Scales: Evidence from Earth System Models |
|---|---|
| Genre | Manuscript |
| Author(s) | Michael Igbinoba, Rachel McCrary, Jacob Stuivenvolt-Allen, Seth A. McGinnis, Mari Tye |
| Abstract | Extratropical cyclones (ETCs) are a major source of cool-season hazardous weather across North America, yet their variability is strongly influenced by large-scale atmospheric and oceanic modes. This study evaluates how the El Niño–Southern Oscillation (ENSO), Pacific–North American pattern (PNA), and North Atlantic Oscillation (NAO) modulate North American ETC activity and assesses whether these relationships are reproduced by the 30-member GFDL SPEAR Large Ensemble relative to ERA5. Spectral analysis shows that SPEAR generally reproduces the dominant periodicities of ENSO, PNA, and NAO, although differences in spectral amplitude remain. SPEAR also captures the characteristic spatial structures of the PNA and NAO and the major North American storm-track corridors, while producing greater ETC track point densities than ERA5 in several regions. Composite analyses reveal particularly strong similarities between ENSO- and PNA-related storm-track responses, including a west-to-east redistribution of ETC activity across North America. In contrast, NAO related variability is concentrated primarily at higher latitudes and over the North Atlantic. These results demonstrate that SPEAR reproduces many observed relationships between large-scale modes of variability and North American ETC activity while exhibiting systematic differences in response magnitude and statistical robustness. |
| Publication Title | |
| Publication Date | Aug 1, 2026 |
| Publisher's Version of Record | https://doi.org/10.5065/2d2d-4695 |
| OpenSky Citable URL | https://n2t.net/ark:/85065/d7dj5m89 |
| OpenSky Listing | View on OpenSky |
| RAL Affiliations | RISC, NSAP |