An international team of climate
experts has taken a new looks at the threat
of global warming and they do not like what
they see. The Earth will not have to warm up
as much as had been though to cause serious
consequences, including more extreme weather
and increasing threats to plants and animals,
the scientists report in this week's online
edition of Proceedings of the National Academy
of Science.
The Intergovernmental panel
on Climate Change estimated that the risk of
increased severe weather would rise with a global
average temperature increase of between 1 degree
Celsius and 2 degrees above 1990 levels.
The National Climate Data Centre
currently reports that global temperatures have
risen 0.12 degree since 1990. Now, researchers
report that "increases in drought, heat
waves, and floods are projected in many regions
and would have adverse impacts, including increased
water stress, wildfire frequency, and flood
risks starting at less than 1 degree of additional
warming above 1990 levels."
Tropical
cyclones
Indeed, "it is now more
likely than not that human activity has contributed
to observed increases in heat waves, intense
precipitation events, and the intensity of tropical
cyclones," concluded the researchers led
by Joel B. Smith of Stratus Consulting Inc.
Other researcher, they noted, have suggested
that "the likelihood of the 2003 heat wave
in Europe, which led to the death of tens of
thousands of people, was substantially increased
by increased greenhouse gas concentration."
The new report comes just a
week after Christopher Field of the Carnegie
Institution for Science told the annual meeting
of the American Association for the Advancement
of Science that humans are now adding carbon
to the atmosphere even faster than in the 1990s.
Carbon emissions have been
growing at 3.5 percent per year since 2000,
up sharply from the 0.9 percent per year in
the 1990s, Field said. The new study says there
is new evidence of greater vulnerability to
climate change for specific populations, such
as the poor and elderly, in not only developing
but also developed countries.
