In the ﬁrst quarter of 2013, winds were generally below normal relative to the long-term (1988 to 2012) average across the northern latitudes of North America and Eurasia, the west coast of the United States, the Sahara region of Africa, southern Argentina and Chile, and New Zealand. At the same time, winds were well above normal across southern Europe and North Africa, as well as in southern Africa, eastern Australia, and most of South America. The largest wind speed anomalies of the quarter, both positive and negative, were found in Europe and North Africa, a pattern that can be explained in part by the Arctic Oscillation (AO).
The AO Index was negative throughout the quarter and strongly negative in March. A negative AO is often associated with a more southerly European winter storm track than usual, bringing much higher than average winds to the Mediterranean, while depressing winds in northern Europe. The Wind Trends Bulletin is a free report that evaluates deviations in global wind conditions from the historical norm on a quarterly basis. The maps contained in this report were derived from the ERA-Interim reanalysis dataset (Dee, D.P., et al, 2011). The anomalies are calculated as a percent deviation from the 1988 to 2012 mean speed at 100m above ground level for the calendar quarter.
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