University experts explain the unusual spring weather
Release Date 27 May 2011
The Walker Institute for Climate System Research at the University of Reading is a world-leader in climate change research.
By drawing together a number of internationally renowned climate system research groups and centres, the Institute delivers a better knowledge and understanding of future climate and its impacts for the benefit of society.
Here, Walker Institute experts explain the recent dry/hot conditions and its effect on agriculture, highlight fascinating facts from the last two months and ask if the extreme weather can be related to climate change.
RECENT WEATHER - Kathy Maskell
"Can we blame the hot, dry weather on climate change? Projections of future climate suggest milder, wetter winters and drier, hotter summers for the UK. We know that across the globe, climate change has probably already increased the chances of drought and very hot summers like Europe saw in 2003. So, the spring conditions we've seen are certainly consistent with the kinds of changes that climate change is likely to bring, but we can't attribute any single event solely to climate change.
"The very dry spring is the result of a ridge of high pressure which was stuck over the UK from mid-March through the whole of April. During the same period at upper levels we've had a split jetstream with rain bearing weather systems to the north and the south, but generally missing the UK. In the dry spring of 2010 the large scale atmospheric circulation was quite different with the jetstream displaced to the south of the UK. So we have had two dry springs running in the UK, but caused by quite different atmospheric conditions."
EFFECT ON AGRICULTURE - Dr Alison Bailey
"The current dry weather has, potentially, the greatest implications for arable farmers in the southern and eastern regions of England. With the very dry spring weather most crops, particularly those on lighter land, are struggling. Yield losses and increased disease pressures are inevitable. However, arable farmers further north and west, who have had some rainfall and whose crops are suffering less, could benefit from the current high price of cereal crops on the global market.
"The drier weather also has implications for the livestock sector. The early start to the growing season has been beneficial, but farmers may face forage shortages later in the year if grass re-grow is poor after the first cut of silage. Forage shortages may also force livestock farmers to use more expensive cereal based feeds. On a more positive note, the warm, dry weather could benefit maize, an alternative forage crop.
"Of all the sectors, it is the horticultural industry which may be the least affected as it is currently reasonably well resourced in terms of irrigation capability, although the issue of adequate water supplies may become an issue if demand exceeds supply."
FACTS AND FIGURES
- April temperatures for central England were the warmest in the entire 353 year record which stretches back to 1659.
- There has been less than 20% of normal rainfall over large parts of England during both March and April. Soils are now exceptionally dry and river flows very low for this time of year.
- During April, the mean maximum temperature in the southeast was 4.9 deg c above average with only 11% of the average rainfall and 155% of the average sunshine.
- The average temperature in London during April was close to what is normally expected in Madrid. Over England and Wales, there were only three sunnier and five drier Aprils in the last 100 years, with March/April 2011 being the driest since 1938.
- In Berkshire, Reading equalled its record for the warmest April day (26.1 degrees on the 23rd) and had its driest April (1.6mm)
- Large areas of England, France and Germany experienced less than 25% of normal rainfall in March and April