New Met Office data shows the United Kingdom is warming in line with global trends
- 31 Aug 2012, 10:04
- Ros Donald
The UK Met Office has just released its latest 30-year
climate average. Readings show the UK's annual mean temperature
calculated over a thirty year time period has risen 0.52 degrees
Celsius over the past two decades. The data handily illustrates
scientists' explanation that long-term warming is continuing
despite temperature fluctuations over shorter
timescales.
Warmer
The Met Office says the biggest departure from previous years is
in the mean UK annual temperature. At 8.84 degrees Celsius, the
annual mean temperature between 1981-2010 is 0.25 degrees Celsius
higher than during the 1971-2000 period, and 0.52 degrees Celsius
warmer than it was between 1961 and 1990.
Mike Kendon of the Met Office National Climate Information
Centre says in a statement:
"At a regional level and for individual
seasons we expect variability on decadal timescales, from natural
cycles, to play a role. Nevertheless, the increases in UK annual
mean temperature are consistent with the trend in warming observed
globally over land."
You can see the new statistics in
maps of the UK and tables for weather stations, regions
and countries on the Met Office website's climate pages. The maps
give an idea of how the warming is distributed over the UK. We have
even made an animated GIF to illustrate the warming better, (click
the image) but you can find non-moving maps and other interesting
things like rainfall patterns on the climate pages.
Click to animate:
The maps
(especially when skilfully animated) illustrate scientists'
argument in the the face of the popular skeptic claim that global
warming has stopped over the past 10-15 years. As we explain in a previous
blog, over 10-to-15 year timescales, natural variation can mask
longer-term rising temperature trends.
While the Met Office's year-to-year temperature maps show all
sorts of variations in the UK's temperature, its 30-year mean
annual temperature data shows a clear warming trend in line with global
surface temperature rise.
The Met Office isn't the only scientific body that provides
climate 'normals'. The US National Oceanic and Atmospheric
Administration's National Climatic Data Center released its 1981-2010
average climate statistics last year. It says the US is now
around 0.28 degrees Celsius (0.5 degrees Fahrenheit) warmer than it
was in 1971-2000, so not far off the UK equivalent rise in
temperature.
Wetter
The Met Office says that the UK now gets 1.154 metres of rain on
average per year. The past 30 years have been wetter - with two per
cent more rainfall than in 1971-2000 and five per cent wetter than
1961-1990. The Met Office stresses that these figures mask regional
and seasonal variations, but says the increase in rainfall is still
consistent with the year-on-year warming trend.
Peter Stott, Head of Climate Monitoring and Attribution at the
Met Office says more rainfall may be partly due to a warmer
atmosphere able to hold more moisture, possibly leading to heavier
rainfall. So, some uncertainty there. In the Met Office's press
release, he says:
"Globally we have seen an increase in
heavy rainfall, but more research needs to be done to be clear on
how a warming atmosphere and variations in weather patterns may be
affecting averages in the UK's regional climate."
Benchmarking
The new UK 30-year average will provide the benchmark for the
Met Office's monthly, seasonal and annual climate summaries, which
provide shorter-term reports on the UK's climate. The Met Office's
summary for July, for example, shows the UK mean temperature was
one degree below the 1981-2010 average. It was the coolest July
since 2000 - so yes, it was an unusually rubbish summer, even if on
average we're getting more sunny days.
Yes, surprisingly, the UK is a sunnier place than it was - not
that it will make anyone feel any better about having to wade
through prodigious amounts of mud all summer. With an average of
nearly 58 days of sunshine a year in the 1981-2010 period, the
nation got 18 hours of sunshine more than in 1971-2000, and an
extra 35 hours if you look back to 1961-1990. Which just goes
to show how counterintuitive long-term climate shifts can seem when
the weather looks so very different.
Update 4pm: We had mixed up the amount of temperature rise
in the first paragraph, and not made it clear that we were talking
about thirty year time periods. This should now be accurate and
clearer. Thanks to Paul Matthews for the spot.