Extra - February 25, 2015
February Down The Ages

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In a good year February offers a preview of the coming spring. As the days grow longer and the sun climbs higher in the sky, the temperature can rise suprisingly high. The 20th century produced no more dramatic example of this than in 1998 when the mercury soared to 67.3F (19.6C) at Worcester on the 13th. At the other extreme February can be unrelentingly wintry: in 1947, 1963 and 1986 some parts of the UK were snow-covered throughout the month.


Thanks to the late Professor Gordon Manley we now have a homogeneous temperature record for central England which extends back for 366 years. This valuable data archive allows us to put recent climatic changes into a historical context, and it enables us to say that the Februarys of the 1990s were in a different league from those of any previous decade. Until then, mean decadal February temperature varied from 36.1F (2.3C) in the 1690s to 40.6F (4.8C) in the 1860s. The figure for the 1990s was 41.2F (5.1C) but it increased marginally to 41.4F (5.2C) for 2005-2014 though there were occasional cold winters including 2010 and 2013.


Averaged geographically over England and Wales and temporally over the last 288 years, February's normal rainfall is 2.55in. The driest decade by far was the 1850s with a mean of 1.75in, whereas all the wet decades occurred during the 20th century, including the 1910s, 1920s, 1950s, 1970s, and 1990s, all with means of nearly 3in. Once again there was a very sharp contrast between the dry 1980s (2.2in) and the wet 1990s (2.9in). By 2005-2014 the rainfall had declined to 2.6in.


Sunshine records began in the mid-1870s, and since then the sunniest decades have been the 1980s and 1990s, both averaging 74 hours, while the cloudiest period occurred in the 1960s with 57 hours. The average for 2005-2014 had increased massively to 78 hours. This is not a result of the introduction of the Clean Air Acts; the reduction in soot-based pollution began in the 1950s so our atmosphere was already much cleaner by the Sixties.


Of the three snowy Februarys already mentioned, 1947 was the most exceptional as it was characterised by repeated heavy snowstorms, leaving level snow two to three feet deep in northeast England. That of 1963 formed part of the longest continuous period of snow-cover known in lowland Britain â' 69 days, from December 26 to March 4.


By Philip Eden


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