Bad weather: We're to blame
2007-07-24 10:13
Washington - Human activities that spur
global warming are largely to blame for changes in rainfall
patterns over the last century, climate researchers reported on
Monday.
The report was released as record rains caused deadly
flooding in Britain and China.
Human-caused climate change has been responsible for higher
air temperatures and hotter seas and is widely expected to lead
to more droughts, wildfires and floods, but the authors say
this is the first study to specifically link it to
precipitation changes.
"For the first time, climate scientists have clearly
detected the human fingerprint on changing global precipitation
patterns over the past century," researchers from Environment
Canada said.
The scientists, writing in the journal Nature, found humans
contributed significantly to these changes, which include more
rain and snow in northern regions that include Canada, Russia
and Europe, drier conditions in the northern tropics and more
rainfall in the southern tropics.
So-called anthropogenic climate change has had a
"detectable influence" on changes in average precipitation in
these areas, and it cannot be explained by normal climate
variations, they wrote.
Living with more floods
Weather experts in Britain raised the possibility that the
current rains there may be related to climate change.
"The global climate models indicate a future for the UK
with drier summers and wetter winters, but storm events in the
summer are predicted to be more frequent and more intense,"
David Butler of the University of Exeter said in a statement.
"So it may well be the case that we will have to learn to live
with more flooding.
Nick Reeves, executive director of the Chartered
Institution of Water and Environmental Management in Britain,
said: "Extreme events such as we have seen in recent weeks
herald the spectre of climate change and it would be
irresponsible to imagine that they won't become more
frequent."
Numerous studies and a report by a panel of scientists
convened by the United Nations have reported with increasing
certainty that human activities - notably the burning of
fossil fuels that emit greenhouse gases - have contributed to
global warming in the last half-century and that the effects of
this are already evident.
The UN's Intergovernmental Panel on Climate Change
estimated temperatures would rise 1.8 to 4.0 degrees Celsius by the year 2100, leading to more hunger, water shortages and extinctions.