Are the teleconnections of Central Pacific and Eastern Pacific El Nio distinct in boreal wintertime?

A meteorological reanalysis dataset and experiments of the Goddard Earth Observing System Chemistry-Climate Model, Version 2 (GEOS V2 CCM) are used to study the boreal winter season teleconnections in the Pacific-North America region and in the stratosphere generated by Central Pacific and Eastern Pacific El Nio. In the reanalysis data, the sign of the North Pacific and stratospheric response to Central Pacific El Nio is sensitive to the composite size, the specific Central Pacific El Nio index used, and the month or seasonal average that is examined, highlighting the limitations of the short observational record. Long model integrations suggest that the response to the two types of El Nio are similar in both the extratropical troposphere and stratosphere. Namely, both Central Pacific and Eastern Pacific El Nio lead to a deepened North Pacific low and a weakened polar vortex, and the effects are stronger in late winter than in early winter. However, the long experiments do indicate some differences between the two types of El Nio events regarding the latitude of the North Pacific trough, the early winter polar stratospheric response, surface temperature and precipitation over North America, and globally averaged surface temperature. These differences are generally consistent with, though smaller than, those noted in previous studies.