Extreme weather becoming more stronger and frequent
Pastor Dale Morgan
*
Extreme weather becoming more stronger and frequent*
By Emmanuel Angleys in Paris
August 10, 2007 01:38pm
Article from: Agence France-Presse
MASSIVE floods, blistering heat waves and bizarre cold snaps since the
start of the year may not be the result of climate change, but extreme
weather has become more stronger and frequent, some scientists say.
The UN's World Meteorological Organisation has reported on findings that
"there is an increasing trend in extreme events observed during the last
50 years".
"Weather and climate are marked by record extremes in many regions
across the world since January 2007," it said.
Examples are not hard to find.
The death toll from the worst monsoon floods to hit South Asia in
decades passed 2000 on yesterday while Britain's recent floods were the
country's worst for 60 years.
Southern Europe has dealt with record temperatures this summer in a
brutal heat wave, South Africa has seen unusually heavy snowfall and the
Argentinian capital Buenos Aires got snow for the first time in 89 years.
Cyclone Gonu, the first documented tropical cyclone in the Arabian Sea,
hit Oman and Iran in June, causing 50 deaths.
But establishing a link between climate change and extreme weather is
controversial.
The UN's weather agency says its Intergovernmental Panel on Climate
Change (IPCC) has found that "the warming of the climate is unequivocal".
Preliminary observations indicated global land surface temperatures in
January and April reached the highest levels ever recorded for those
months, it said.
"Climate change projections indicate it to be very likely that hot
extremes, heat waves and heavy precipitation events will continue to
become more frequent,'' it said recently.
A study by researchers from the US National Centre for Atmospheric
Research and the Georgia Institute of Technology says about twice as
many Atlantic hurricanes form each year on average than a century ago.
It blames warmer sea surface temperatures and altered wind patterns
associated with global climate change for "fueling much of the increase".
But scientists caution there is not enough evidence to blame global
warming for recent extreme weather, and there are those who say there is
no proof that extreme weather events are becoming more frequent.
Barry Gromett of Britain's Met Office weather service said much of the
extreme weather was down to variability in the climate, which is
affected by greenhouse gases but also other factors such as El Nino.
El Nino events are when drastic changes in sea temperatures in tropical
areas affect atmospheric pressure in the Pacific Ocean region, having a
knock-on effect on rainfall.
"There's a danger in taking isolated incidents in any given year and
attributing this to something like climate change,'' he said.
"It's really important to look for trends over a longer period of time.
More heat equals more moisture equals probably higher rains, so in that
respect some of it ties in quite nicely (with climate change).
"But there are many different facets that appear to contradict each other.''
A study by British Met Office experts released yesterday found that
natural weather variations actually helped offset the effects of global
warming the past couple of years, but with temperatures set to rise to
new records beginning in 2009.
Jean Jouzel, a climatologist who represents France on the IPCC, said:
"several more years would be needed to establish a link, or to not
establish a link, between these extremes and global warming.''
"Are the extremes really changing? It's not so simple, because by
definition, the extremes are rare events, and to come up with
statistics, some hindsight is needed,'' he said.