OSLO (Reuters) - When bears wake early from hibernation,
Australia suffers its worst drought in 100 years and multiple
hurricanes hammer Florida should we believe The End is nigh?
That's the nub of a debate over the human impact on global
warming that pits scientists who say such anomalies are signs of
impending doom against those who say they are evidence that the
earth's climate has always been chaotic.
Amid those signs of warming, for instance, Algeria had its worst
snow in 50 years last month.
This month 141 countries will attempt the best effort to arrest a
forecasted continued rise of global temperatures by bringing into
force the Kyoto protocol. The treaty is an agreement aimed at
curbing emissions of gases from cars and industry, blamed for
trapping the earth's heat.
"Dealing with (global warming) will not be easy. Ignoring it will
be worse," the United Nations says.
At issue is how humanity should deal with global warming, the
risks of which are not yet fully understood despite broad
consensus among scientists that people are heating the planet
with the emission of such heat-trapping gases as carbon dioxide.
Not everyone is convinced of Kyoto's importance. President Bush
pulled the United States out of Kyoto in 2001, reckoning it will
be too costly and that it wrongly excludes developing countries
from cuts in emissions until 2012.
Bush accepts there are risks from climate change but says more
research is needed -- exasperating even allies who say that the
time for Kyoto-style caps on emissions is now.
"We're talking about spending perhaps $150 billion a year on
Kyoto with fairly little benefit," said Bjorn Lomborg, Danish
author of "The Skeptical Environmentalist."
Lomborg said that money would be better spent on combating AIDS
and malaria, malnutrition and promoting fair global trade.
Many climate scientists say that floods, storms and droughts will
become more frequent and that climate change is the most severe
long-term threat to the planet's life support systems.
Rising temperatures could force up ocean levels, swamping coasts
and low-lying Pacific islands and drive thousands of species to
extinction by 2100.
But full proof is elusive.
A Caribbean hurricane season last year, when Florida was the
first U.S. state to be hit by four hurricanes in one season since
1886, might be a fluke. Bears are waking in Estonia in the
warmest winter in two centuries, again a possible climate freak.
"Imagine a pot of boiling water on the stove. If I turn up the
heat I can't say that each bubble is from the extra heat," said
Mike MacCracken, chief scientist for climate change programs at
the Climate Institute, a Washington think-tank.
"But there are more bubbles and they're larger," he said, adding
it was best to act now rather than risk disaster.
The warmest year at the world's surface since records began in
the 1860s was 1998, followed by 2002, 2003 and 2004, according to
the U.N.'s World Meteorological Organization.
World surface temperatures have risen by 0.6 degrees centigrade
(1.1 degrees Fahrenheit) since the late 1800s when the Industrial
Revolution started in Europe.
The Intergovernmental Panel on Climate Change, a group of 2,000
scientists which advises the United Nations, projects a further
rise of 1.4-5.8 degrees centigrade by 2100. Even the lowest
forecast would be the biggest century-long rise in 10,000 years.
Yet the evidence for a human impact on the climate falls short of
being "beyond a reasonable doubt," the standard of proof needed
in a criminal court.
"It is really for a legal mind to decide whether the scientific
consensus of the IPCC provides findings that are beyond
reasonable doubt," said IPCC chairman Rajendra Pachauri.
Many so-called skeptics concede that carbon dioxide stokes global
warming but say U.N. models of what will happen in 2100 are about
as reliable as tomorrow's weather forecast.
Other factors, like variations in the sun's radiation, ash from
volcanoes or other natural effects may have a bigger role, they
say. The IPCC tries to account for all such effects.
"My bottom line is that natural variations are much larger than
the human component," said George Taylor, state climatologist for
Backers of Kyoto say it is a blueprint for regulating the climate
by cutting rich nations' emissions of carbon dioxide by 5.2
percent below 1990 levels by 2008-12. Supporters say that much
deeper cuts will be needed after 2012.
In a landmark phrase in 1995, the IPCC said that the balance of
evidence suggested a discernible human influence on the global
climate. And its 2001 report spoke of "new and stronger" evidence
that humans had caused warming in the past 50 years.
Pachauri said that he hoped the next report, in 2007, would fill
in gaps in knowledge. But Washington has given no signs of being
won over to Kyoto, preferring to focus on funding new clean
technologies like hydrogen.
The Environmental Protection Agency says:
"The fundamental scientific uncertainties are these: How much
more warming will occur? How fast will this warming occur? And
what are the potential adverse and beneficial effects? These
uncertainties will be with us for some time, perhaps decades."