Deadly
Hot Summers
To Become The Norm
By Steve Connor
02 December 2004
The
Independent
Blisteringly
hot summers similar to the one in 2003 when thousands of people in continental
Europe died of heatstroke will become commonplace because of climate
change, a study has found.
Scientists estimate
global warming has already doubled the risk of similar hot summers,
and if the climate continues to change, they will occur every couple
of years.
It is estimated
that between 22,000 and 35,000 people died heat-related deaths in Europe
during the summer of 2003, when soaring temperatures and drought also
caused widespread forest fires and crop failures in the Mediterranean
area.
Until now it has
not been possible to say with any accuracy how much of this extra heat
was the result of man-made global warming and how much of it was the
result of a naturally warm summer. But Peter Stott, of the Met Office's
Hadley Centre, and Daithi Stone and Myles Allen, of Oxford University,
have found a way of teasing apart the human and natural influences on
the temperatures measured across Europe in 2003. Using a computer model
of the climate, they found the extra heat that made the summer of 2003
the hottest for at least 500 years was largely the result of human influences,
such as the burning of fossil fuel which exacerbates the planet's greenhouse
effect.
Dr Stott said: "We
simulated 2003 summer temperatures over Europe, with and without the
effect of man's activities, and compared these with observations."
"We found that
although the high temperature experienced was not impossible in a climate
unaltered by man, it is very likely that greenhouse gases have at least
doubled the risk.
"Our best estimate
is that such a heatwave is now four times more likely as a result of
human influence on climate."
The study, published
in the journal Nature, calculates that human influence is to blame for
75 per cent of the increased risk.
At the rate at which
the climate is changing, the scientists estimate that by the 2040s more
than half of the summers will be warmer than that of 2003, and by the
end of the century a summer similar to 2003 will be classed as unusually
cold.
"Anthropogenic
[man-made] warming trends in Europe imply an increased probability of
very hot summers," the scientists wrote. "Nevertheless, it
seems likelythat past human influence has more than doubled the risk
of European mean summer temperatures as hot as 2003. And with the likelihood
of such events projected to increase 100-fold over the next four decades,
it is difficult to avoid the conclusion that potentially dangerous anthropogenic
interference is already under way."
Lawyers wishing
to pin blame on organisations or governments for exacerbating global
warming may use scientific analysis as evidence in a court of law, said
Dr Allen, who has co-authored a study into the legal implications of
such research with Richard Lord, QC.
"Quantifying
the costs of climate change requires being able to separate natural
from man-made contributions to weather risk," Dr Stott said.Doug
Parr of Greenpeace said: "This study could be a stepping stone
to holding climate villains to account.
"Like the tobacco
industry big polluters could face massive lawsuits. Polluters should
know that if they ignore moral arguments for action, legal liability
could hit them."