A long-term climatology of North Atlantic polar lows

A dynamical downscaling of the 6-hourly 1948-2006 NCEP/NCAR re-analyses for the subarctic region of the North Atlantic has been used to derive a climatology of polar lows by means of a tracking algorithm based on the simulated bandpass filtered MSLP-fields. This climatology is consistent with the li...

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Bibliographic Details
Published in:Geophysical Research Letters
Main Authors: Zahn, M., von Storch, H.
Format: Article in Journal/Newspaper
Language:English
Published: 2008
Subjects:
Online Access:http://hdl.handle.net/11858/00-001M-0000-0018-2538-D
Description
Summary:A dynamical downscaling of the 6-hourly 1948-2006 NCEP/NCAR re-analyses for the subarctic region of the North Atlantic has been used to derive a climatology of polar lows by means of a tracking algorithm based on the simulated bandpass filtered MSLP-fields. This climatology is consistent with the limited observational evidence in terms of frequency and spatial distribution. The climatology exhibits strong year-to-year variability but weak decadal variability and a negligible trend. A Canonical Correlation Analysis describes the conditioning of the formation of polar lows by characteristic meridional seasonal mean flow regimes, which favor cold air outbreaks and upper air troughs. Citation: Zahn, M., and H. von Storch (2008), A long-term climatology of North Atlantic polar lows, Geophys. Res. Lett., 35, L22702, doi:10.1029/2008GL035769.