Precipitation extremes have become the new norm in many parts of the world, and the United Kingdom is no exception. After two abnormally dry winters, many parts of England are currently experiencing their worst drought in over three decades. Water restrictions were introduced earlier this year and currently affect 20 million people in southeastern England, including London.
The BBC reports that some areas of England received less than 60 percent of their average seasonal rainfall last winter. Yet the precipitation deficit goes back to 2010, when England saw its 11th driest year on record. Well-below-average precipitation continued into 2011, slowly depleting groundwater and reservoirs across the country. For southern England, the past 24 months have been the driest period on record since precipitation records began in 1910.
What’s causing the lack of rain? How bad is the drought? Keep reading...
If drought situations don’t improve, hosepipe bans could remain in place until 2013. These restrictions curb private water usage for nonessential purposes, such as watering gardens or washing cars.
Map: England in drought
What’s causing the lack of rain?
Over the past year, below-average precipitation has affected not only England but also other parts of Western Europe, including Spain and France. England, however, has seen some of the driest conditions relative to normal.
Frequent high pressure systems centered over the UK or Western Europe have blocked Atlantic low pressure from delivering much needed moisture. These high pressure areas often bring dry, southerly winds off the European continent and bend the jet stream north of the British Isles (or near Scotland, which has in fact seen near normal rainfall).
Satellite image: Sunny, cloud-free UK seen in late March 2012
How bad is the drought?
The current dry spell is being compared to the UK’s 1976 drought when a hot summer and short water supplies had a significant socioeconomic impact. Yet unlike the 1976 drought when very dry conditions stretched across the entire UK, this year’s rain deficit is limited to England and parts of Wales (the Met Office has a good visual comparison).
Despite its smaller geographic extent, the 2012 drought could become longer in duration if low rainfall continues into spring and summer. A report released by the UK Environment Agency last week suggests that drier-than-normal conditions may persist into early 2013. The Guardian reports that officials are already preparing for a third consecutive drier-than-normal winter. Such a scenario would significantly affect England’s agricultural sector, which is already bracing for higher fruit and vegetable prices this summer.
Putting a dent in England’s drought requires light, steady rains over a prolonged period. The Environment Agency has indicated that any spring and summer rains will be beneficial, but “unlikely to improve the underlying drought situation.”
Q&A: England drought (BBC)
Current Drought Situation in the UK (Environment Agency)
UK Global Drought Monitor
UK experiences unseasonably warm March (Capital Weather Gang)
UK sees record October heat (Capital Weather Gang)