Aspects of a Northern Hemisphere Atmospheric Blocking Climatology

From: Journal of the Atmospheric Sciences | Date: May 1, 2008| Author: | Copyright information

ABSTRACT

A comprehensive climatology of Northern Hemisphere blocking is described based on a PV-θ wave-breaking index at the latitude of the climatological storm track and using the 40-yr ECMWF Re-Analysis (ERA-40) dataset. The general characterization of blocking regions is in agreement with most other studies, though more detail is provided here. In the annual average, blocking is most prevalent in the large region from the eastern Atlantic Ocean through Europe to central Asia with a secondary region in the central and eastern Pacific Ocean. Using a blocking criterion with the ...

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