Investigations of Polar Air Stream Cyclogenesis Based on Numerical Simulations with a Mesoscale Model

摘要

Extratropical cyclogenesis has long been considered through the paradigm provided by the Norwegian cyclone model, in which cyclone evolution occurs through a wave development along a polar front separating tropical and polar air masses. However, smaller-scale cyclones are observed to form on the cold air side of the polar front, especially over oceanic regions during the winter half of the year. It is to the evolution of these cyclones that the authors apply the phrase 'polar air stream'.