Extratropical Cyclogenesis Changes in Connection with Tropospheric ENSO Teleconnections to the North Atlantic: Role of Stationary and Transient Waves ...
This study investigates mechanisms for changes in wintertime extratropical cyclogenesis over North America and the North Atlantic during different phases of El Niño–Southern Oscillation (ENSO). Insights into the relationship between the ENSO–North Atlantic teleconnection and the cyclogenesis changes...
| Main Authors: | , , , |
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| Format: | Article in Journal/Newspaper |
| Language: | English |
| Published: |
ETH Zurich
2018
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| Subjects: | |
| Online Access: | https://dx.doi.org/10.3929/ethz-b-000302371 http://hdl.handle.net/20.500.11850/302371 |
| Summary: | This study investigates mechanisms for changes in wintertime extratropical cyclogenesis over North America and the North Atlantic during different phases of El Niño–Southern Oscillation (ENSO). Insights into the relationship between the ENSO–North Atlantic teleconnection and the cyclogenesis changes are provided by diagnosing the relative roles of stationary wave propagation and transient eddies in setting cyclogenesis-conducive large-scale circulation anomalies. During La Niña winters, Rocky Mountain and Greenland cyclogenesis are enhanced, while Gulf Stream cyclogenesis is reduced. Diagnostics suggest that stationary waves of tropical origin work in tandem with transient eddies to amplify the ridge over the northeastern Pacific, establishing background flow anomalies that favor Rocky Mountain cyclogenesis; downstream, more transient eddies with an anticyclonic tilt push the North Atlantic jet poleward, favoring cyclogenesis near Greenland, while contributions from stationary waves are small. During central ... : Journal of the Atmospheric Sciences, 75 (11) ... |
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