Geophysical Research Letters, 25, 2413-2416
Storm track signature in total ozone during the northern
hemisphere winter
Yvan J. Orsolini, David B. Stephenson, and Francisco J. Doblas-Reyes
Météo-France/CNRM, 42 Avenue Coriolis
31057 Toulouse Cedex, France
Total ozone has long been known to correlate with tropospheric synoptic
eddy activity, with low total ozone being associated with anticyclonic
conditions. Such eddy activitiy is particularly intense in the storm tracks
regions of the North Atlantic and Pacific oceans during boreal winter.
An Eulerian diagnostic was introduced by Blackmon et al. (1977) to investigate
storm tracks, based on bandpass filtering the 500 mb geopotential height
for synoptic time scales. Wintertime daily satellite observations of total
ozone are analyzed using the same Eulerian approach, and storm track signatures
in total ozone, referred to as ozone tracks, can be discerned; yet the
North Pacific ozone track is substantially weaker than the North Atlantic
one. This asymmetry is partly due to the existence of intense ozone mini-hole
events in the Atlantic sector, which cause large total ozone variations.
We further show that in winter 1996/97, the Atlantic storm track and the
corresponding ozone track were displaced westward and northward due to
persistent anticyclonic conditions over western Europe. Total ozone fluctuations
on synoptic time scales were therefore also reduced over western Europe,
and were more confined to the western part of the North Atlantic.