'Worst' of climate predictions are the most likely
Ground-breaking
research on cloud behaviour and global warming says "catastrophic"
increase of 4°C or more by 2100 should be expected.
by Jon Queally
New research by a team of scientists looking at the impact of cloud
behaviour on planetary climate change says that "the worst" and
"catastrophic" predictions offered by previous studies on the rate of
global warming this century are much more likely than the less severe
scenarios offered by others.
According to Dr. Steven Sherwood, lead author of the study and a
specialist in climate and cloud formations at the University of New
South Wales in Australia, cloud patterns in an increasingly warming
world are likely to exacerbate global temperature increases overall, not
mitigate warming as some models have suggested.
"This study breaks new ground twice," Sherwood said in an interview
with the Guardian. "First by identifying what is controlling the cloud
changes and second by strongly discounting the lowest estimates of
future global warming in favour of the higher and more damaging
estimates."
The research predicts that global temperatures will likely rise at
least 4°C by 2100 and potentially more than 8°C by 2200 if carbon
dioxide emissions are not reduced and serious actions by governments and
society are not taken.
Such drastic increases, Sherwood told the Guardian would be
"catastrophic rather than simply dangerous."
Specifically, the study looked at how already warming temperatures
impact the ability of clouds to form at high altitudes, because that
ability can greatly impact the way in which large clouds help the planet
reflect or absorb the sun's heat. One of the long-acknowledged
shortcomings of other climate computer models - which drive much of the
work of climate change predictions - is the difficulty of accurately
projecting cloud behaviour under complex, future conditions. By tackling
that problem, say Sherwood and his colleagues, their research "cracks
open one of the biggest problems in climate science." As the Sydney
Morning Herald reports: Will Steffen, an adjunct professor at Australian
National University and a member of the Climate Council, said the paper
was ''right out on the forefront of the sort of research we need to do
on clouds''.
''The more we get research like from Professor Sherwood and his
group, the more confidence we'll have in being able to say where in that
range the temperature increase is likely to fall.''
The CO2 level of the atmosphere in 2012 was 393 parts per million, or
41 percent higher than in pre-industrial times, the World Meteorological
Organisation said.
The level is rising at an accelerating rate - more than two parts per
million a year - as humans burn more fossil fuels and cut down forests.
Global temperatures have risen about 0.8 degrees since about 1880,
with system lags and air pollution reflecting sunlight partly explaining
why the rise has not been higher. ''We've been hoping for the best and
not planning for the worst,'' Prof Sherwood said.
''And now it's looking like the best is not very likely.''
In 2012, a study by the World Bank-an institution not typically known
for sounding the alarm over industrial, human-caused global warming -
also said that a 4°C temperature rise was not only possible, but likely
if humanity did not change course.
According to Kim Yong Kim, the bank's president, the resulting
impacts of a planet that warm would likely "make the world our children
inherit a completely different world than we are living in today."
And those kinds of warnings only mirror the consistent and nearly
unanimous consensus of the international scientific community when it
comes to temperature increases that exceed the 2°C increase that world
governments have set as the benchmark not to exceed this century.
The problem, of course, is that no agreements or promises have
resulted in actual emission reductions. In fact, annual global emissions
continue to increase even as the warnings escalate.
- Third World Network Features. |