http://www.livescience.com/24960-climate-change-world-bank-report.html
The 'blue marble' of earth gets a makeover in this view of the
arctic as seen by the Suomi NPP satellite. Image released June 18,
2012.
CREDIT: NASA/GSFC/Suomi NPP.
Climate scientists who have been warning of the dangerous
effects of global warming now have the World Bank on their side,
after a new report from that organization calling for action to
prevent climate catastrophe.
"The World Bank did a great service to society by issuing this
report," said Michael Mann, a climate researcher at Pennsylvania
State University and the author of "The
Hockey Stick and the Climate Wars" (Columbia University Press,
2012).
Climate deniers often claim that solutions to global warming are
part of a "global socialist agenda," Mann told LiveScience.
"The fact that the World Bank — an entity committed to free
market capitalism — has weighed in on the threat of climate change
and the urgency of acting to combat it, puts the nail in the coffin
of that claim," he said.
A changing world
The report, issued by the Potsdam Institute for Climate Impact
Research and Climate Analytics for the World Bank, urges nations to
work to prevent the Earth from warming 7.2 degrees Fahrenheit (4
degrees Celsius) past preindustrial averages. Already, global mean
temperatures are running about 1.3 degrees F (0.8 degrees C) hotter
than before the onset of the industrial revolution.
Likewise, carbon-dioxide concentration in the atmosphere is high
and rising. As of September, the concentration was 391 parts per
million,
a record high, up from a preindustrial 278. That number is now
rising by about 1.8 parts per million each year.
All of these changes are accompanied by ice loss, including
accelerating melting in Greenland, according to research
published this week. As a result, average sea level has risen
between 6 and 8 inches (15 and 20 centimeters) or so on average
around the world. [8
Ways Global Warming Is Already Changing the World]
Dire warnings
But what the World Bank warns of is an even bleaker future. Even
if the world's nations deliver on their promises of emission limits
and global warming mitigation, there is a 20 percent chance that
the world will hit the 4 degrees C mark by 2100, according to the
report. If emissions continue as is, the planet may reach that
point by the 2060s.
International negotiators have agreed that warming should be
limited to just half that, or 3.6 degrees F (2 degrees C), in that
time. A world that is 2 degrees warmer
would have its own consequences, but it is crucial to hold that
line, the World Bank report argues. A 4-degree warming would mean a
sea-level rise of 1.6 to 3.2 feet (0.5 to 1 meter) on average, with
the tropics catching the brunt of the change.
Climate research also suggests tropical storms would strengthen
and drought would increase across much of the tropical and
subtropical world.
"A world in which warming reaches 4 degrees C above
preindustrial levels (hereafter referred to as a 4 degree C world),
would be one of unprecedented heat waves, severe drought, and major
floods in many regions, with serious impacts on human systems,
ecosystems, and associated services," the authors wrote in the
World Bank report.
Climate scientists agree.
"I am inclined to think that things will break before we get
there," Kevin Trenberth, a climate scientist at the National Center
for Atmospheric Research, said of a 4-degree-C world. Ecosystems
would change so much and agriculture would be so disrupted that the
result would likely be "major strife, conflicts and loss of
population," Trenberth told LiveScience.
Among the flashpoints, according to the World Bank report, would
be sparse water availability, food insecurity and loss of resources
such as coral
reefs, which are threatened by acidification as more carbon
dioxide is dissolved in the oceans. Coral reefs provide not only
food to many local economies, but also tourism dollars. Areas
becoming unsustainable would likely lead to mass exodus, creating
environmental refugees, Mann said. [10
Surprising Results of Global Warming]
Avoiding the 4-degree world
Avoiding the 4-degree-warmer world is a matter of political
will, said Mann, who sees signs of optimism, including increased
awareness and more calls to transition away from fossil fuels.
"The
alternative energies (wind, solar, geothermal, etc) are there,"
Mann wrote in an email to LiveScience. "We just need to deploy and
scale them up by investing immediately in the necessary
infrastructure."
Slowing the warming may be as useful as stopping it, Trenberth
said.
"It is not just the absolute amount of warming, but also the
rate at which
we change things to get there," he said. "Two degrees warming
in 50 years is extremely stressful, but 2 degrees warming in
500 years is perhaps manageable through adaptation."
If the world fails to act, the world will become a more
disrupted, damaged place, the World Bank concluded — and the poor
will suffer most.
"The projected 4°C warming simply must not be allowed to occur —
the heat must be turned down," the authors wrote. "Only early,
cooperative, international actions can make that happen."
