Wind climate changes in the past

The distribution of the most severe storms over the UK and Iceland is likely to have changed since the 1950s. Although there has been an increase in the number of severe storms between October and March in each year in most regions, there has been a shift towards fewer very severe events over Iceland. Northern UK shows a mixed pattern of change. There are many more regional severe events in recent decades but no significant distribution change between the two periods studied and no significant increase in severe storms. The central and southern UK regions show a tendency towards more ‘‘very severe’’ storms in latter decades with the number of severe events in central UK having more than doubled (1).

Although southern UK shows little change in the number of severe events, there is evidence for their intensification in the most recent decades. Overall, the UK has seen a significant increase in the number of severe storm events over the past 50 years which in general are related to the long-term fluctuations of the NAO. An exception to this is the non-significant relationship between the NAO and severe storms over the UK in October to December, the reason for which is not clear (1).

The difference between the distributions of severe storms between Iceland and the UK may imply a possible shift in the North Atlantic storm track, with significant implications given that the majority of people (more than 30 million) in this region of study live in southern Britain (1).

With this relatively short record it is hard to say whether these changes are unusual over longer time periods. Indeed is was shown that it is unlikely that ‘‘storminess’’ has significantly changed over the past 200 years in northern Europe (2).

Iceland has around two to three times as many severe storms as the UK. The annual average number of severe storms varies from less than one in southern Britain to around four in Iceland (1).

References

The references below are cited in full in a separate map 'References'. Please click here if you are looking for the full references for Iceland.

1. Alexander et al. (2005)
2. Bärring and von Storch (2004), in: Alexander et al. (2005)