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Find out what's really happening here...
In case the present cold spell in the UK gives the impression that global warming has gone away, it might be worth noting that last week eastern Europe and south eastern Europe had temperatures well above normal (see temperature anomalies below). Further east, south-western Russia was up to 8C above normal.
Temperature anomaly over Europe (Nov 21-27 2010) from NOAA.
To the west of us, very warm air moved over Greenland. For example, on 29 November a temperature of +11C was recorded at Sdr Stroemfjord and +9C at Jacobshavn.
This was all part of a huge rather stationary wave pattern that is nicely shown by the average pressure field high in the atmosphere for 26-29 November, given below.
High level atmospheric circulation showing blocking pattern over western Europe (from the University of Reading, Department of Meteorology).
The pattern is known as blocking. We had a lot of blocking last winter which gave us the cold winter. When it occurs repeatedly in the right location in summer we get the very hot weather of 2003 and 2006.
This article was written by Professor Sir Brian Hoskins, Director of the Grantham Institute for Climate Change and Professor of Meteorology at the University of Reading and Associate of the Walker Institute.
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