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by Jon Austin
December 21, 2015
from
Express Website
Fossil fuel burning
gives of aerosols
which reflect
sunlight
BURNING Fossil Fuels
and Cutting Down Trees
causes Global COOLING.
A Shock New NASA Study has
Found.
Major theories about what causes temperatures to rise have been
thrown into doubt after NASA found the Earth has cooled
in areas of heavy industrialization where more trees have been lost
and more fossil fuel burning takes place.
Environmentalists have long argued the burning of fossil fuels in
power stations and for other uses is responsible
for global warming and predicted
temperature increases because of the high levels of carbon dioxide
produced - which causes the global greenhouse effect.
While the findings did not dispute the effects of carbon dioxide on
global warming, they found aerosols - also given off by burning
fossil fuels - actually cool the local environment, at
least 'temporarily.'
The research was carried out to see if current climate change models
for calculating future temperatures were taking into account all
factors and were accurate.
A
NASA spokesman said:
"To quantify climate change,
researchers need to know the Transient Climate Response (TCR)
and Equilibrium Climate Sensitivity (ECS)
of Earth.
On December 7, NASA's Aqua satellite
captured this image
of eastern China
being inundated by
thick smog
NASA
"Both values are projected global
mean surface temperature changes in response to doubled
atmospheric carbon dioxide concentrations but on different
timescales.
"TCR is characteristic of short-term predictions, up to a
century out, while ECS looks centuries further into the future,
when the entire climate system has reached equilibrium and
temperatures have stabilized."
The spokesman said it was "well known"
that aerosols such as those emitted in volcanic eruptions and power
stations, act to cool Earth, at least temporarily, by reflecting
solar radiation away from the planet.
He added:
"In a similar fashion, land use
changes such as deforestation in northern latitudes result in
bare land that increases reflected sunlight."
Kate Marvel, a climatologist at
GISS and the paper's lead author (Implications
for Climate Sensitivity from the Response to Individual Forcings),
said the results showed the "complexity" of estimating future global
temperatures.
She said:
"Take sulfate aerosols, which are
created from burning fossil fuels and contribute to atmospheric
cooling. They are more or less confined to the northern
hemisphere, where most of us live and emit pollution."
NASA found a net
cooling in the northern hemisphere
due to industrial
activity
GETTY
"There's more land in the northern
hemisphere, and land reacts quicker than the ocean does to these
atmospheric changes.
"Because earlier studies do not account for what amounts to a
net cooling effect for parts of the northern hemisphere,
predictions for TCR and ECS have been lower than they should
be."
The study found existing models
for climate change had been too
simplistic and did not account for these factors.
The spokesman said:
"There have been many attempts to
determine TCR and ECS values based on the history of temperature
changes over the last 150 years and the measurements of
important climate drivers, such as carbon dioxide.
"As part of that calculation, researchers have relied on
simplifying assumptions when accounting for the temperature
impacts of climate drivers other than carbon dioxide, such as
tiny particles in the atmosphere known as aerosols, for example.
Climate scientist Gavin Schmidt,
the director of NASA's Goddard Institute for Space Studies (GISS)
in New York and a co-author on the study, published in the journal
Nature Climate Change, said:
"The assumptions made to account for
these drivers are too simplistic and result in incorrect
estimates of TCR and ECS.
"The problem with that approach is that it falls way short of
capturing the individual regional impacts of each of those
variables,” he said, adding that "only within the last ten years
has there been enough available data on aerosols to abandon the
simple assumption and instead attempt detailed calculations."
But, rather than being good news, NASA
has concluded the lack of taking these factors into account means
existing climate change models have underestimated at the
future impact on global temperatures will be.
NASA looked at climate changing activities
across the globe for
the study
GETTY
NASA researchers at GISS accomplished a
first ever feat by calculating the temperature impact of each of
these variables,
... based on historical observations
from 1850 to 2005 using a massive ensemble of computer simulations.
The spokesman said:
"Analysis of the results showed that
these climate drivers do not necessarily behave like carbon
dioxide, which is uniformly spread throughout the globe and
produces a consistent temperature response; rather, each climate
driver has a particular set of conditions that affects the
temperature response of Earth.
"Because earlier studies do not account for what amounts to a
net cooling effect for parts of the northern hemisphere,
predictions for TCR and ECS have been lower than they should be.
"This means that Earth's climate sensitivity to carbon dioxide -
or atmospheric carbon dioxide's capacity to affect temperature
change - has been underestimated, according to the study."
The Intergovernmental Panel on
Climate Change, which draws its TCR estimate from earlier
research, places the future estimate rise at 1.8°F (1.0°C).
But the new NASA study dovetails with a GISS study published last
year that puts the TCR value at 3.0°F (1.7° C).
Mr Schmidt said:
"If you've got a systematic
underestimate of what the greenhouse gas-driven change would be,
then you're systematically underestimating what's going to
happen in the future when greenhouse gases are by far the
dominant climate driver."
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