A new greenhouse gas that is
7,000 times more powerful than
carbon dioxide at warming the
Earth has been discovered by
researchers in Toronto.
The newly discovered gas,
perfluorotributylamine (PFTBA),
has been in use by the electrical
industry since the mid-20th
century.
The chemical, that does not
occur naturally, breaks all records
for potential impacts on the
climate, said the researchers at
the University of Toronto's
department of chemistry.
"We claim that PFTBA has the
highest radiative efficiency of any
molecule detected in the
atmosphere to date," said Angela
Hong, one of the co-authors.
The study , published in the
journal Geophysical Research
Letters, found PFTBA was 7,100
times more powerful at warming
the Earth over a 100-year time
span than CO2.
Concentrations of PFTBA in
the atmosphere are low – 0.18
parts per trillion in the Toronto
area – compared to 400 parts per
million for carbon dioxide. So
PFTBA does not in any way
displace the burning of fossil fuels
such as oil and coal as the main
drivers of climate change.
Dr Drew Shindell, a
climatologist at Nasa's Goddard
Institute for Space Studies, said:
"This is a warning to us that
this gas could have a very very
large impact on climate change –
if there were a lot of it. Since
there is not a lot of it now, we
don't have to worry about it at
present, but we have to make
sure it doesn't grow and become a
very large contributor to global
warming.".
He said a number of recent
studies had drawn attention to
other potential new greenhouse
gases which, like PFTBA, pack a
lot of warming potential in each
molecule but are not very
prevalent in the atmosphere.
Such studies were a warning
against increasing uses of such
compounds without first
understanding their impact on
climate change, he added.
"From a climate change
perspective, individually, PFTBA's
atmospheric concentration does
not significantly alert the
phenomenon of climate change,"
Hong said. "Still the biggest
culprit is CO2 from fossil fuel
emissions."
But PFTBA is long-lived. The
Toronot researchers estimated
PFTBA remains in the atmosphere
for about 500 years, and unlike
carbon dioxide, that is taken up
by forests and oceans, there are
no known natural "sinks" on Earth
to absorb it.
"It is so much less than
carbon dioxide, but the important
thing is on a per molecule basis,
it is very very effective in
interacting with heat from the
Earth," she said. "Individually
each molecule is able to affect the
climate potentially and because its
lifetime is so long it also has a
long-lasting effect."
Hong said the discovery of
PFTBA and its warming potential
raises questions about the climate
impacts of other chemicals used in
industrial processes.
PFTBA has been in use since
the mid-20th century for various
applications in electrical
equipment, such as transistors and
capacitors. The researchers said it
was unclear how widespread its
use was today.
It belongs to an entire class of
chemicals used for industrial
applications whose effects on the
atmosphere remain unknown.
"PFTBA is just one example of
an industrial chemical that is
produced but there are no policies
that control its production, use or
emission," Hong said. "It is not
being regulated by any type of
climate policy."
7,000 times more powerful than
carbon dioxide at warming the
Earth has been discovered by
researchers in Toronto.
The newly discovered gas,
perfluorotributylamine (PFTBA),
has been in use by the electrical
industry since the mid-20th
century.
The chemical, that does not
occur naturally, breaks all records
for potential impacts on the
climate, said the researchers at
the University of Toronto's
department of chemistry.
"We claim that PFTBA has the
highest radiative efficiency of any
molecule detected in the
atmosphere to date," said Angela
Hong, one of the co-authors.
The study , published in the
journal Geophysical Research
Letters, found PFTBA was 7,100
times more powerful at warming
the Earth over a 100-year time
span than CO2.
Concentrations of PFTBA in
the atmosphere are low – 0.18
parts per trillion in the Toronto
area – compared to 400 parts per
million for carbon dioxide. So
PFTBA does not in any way
displace the burning of fossil fuels
such as oil and coal as the main
drivers of climate change.
Dr Drew Shindell, a
climatologist at Nasa's Goddard
Institute for Space Studies, said:
"This is a warning to us that
this gas could have a very very
large impact on climate change –
if there were a lot of it. Since
there is not a lot of it now, we
don't have to worry about it at
present, but we have to make
sure it doesn't grow and become a
very large contributor to global
warming.".
He said a number of recent
studies had drawn attention to
other potential new greenhouse
gases which, like PFTBA, pack a
lot of warming potential in each
molecule but are not very
prevalent in the atmosphere.
Such studies were a warning
against increasing uses of such
compounds without first
understanding their impact on
climate change, he added.
"From a climate change
perspective, individually, PFTBA's
atmospheric concentration does
not significantly alert the
phenomenon of climate change,"
Hong said. "Still the biggest
culprit is CO2 from fossil fuel
emissions."
But PFTBA is long-lived. The
Toronot researchers estimated
PFTBA remains in the atmosphere
for about 500 years, and unlike
carbon dioxide, that is taken up
by forests and oceans, there are
no known natural "sinks" on Earth
to absorb it.
"It is so much less than
carbon dioxide, but the important
thing is on a per molecule basis,
it is very very effective in
interacting with heat from the
Earth," she said. "Individually
each molecule is able to affect the
climate potentially and because its
lifetime is so long it also has a
long-lasting effect."
Hong said the discovery of
PFTBA and its warming potential
raises questions about the climate
impacts of other chemicals used in
industrial processes.
PFTBA has been in use since
the mid-20th century for various
applications in electrical
equipment, such as transistors and
capacitors. The researchers said it
was unclear how widespread its
use was today.
It belongs to an entire class of
chemicals used for industrial
applications whose effects on the
atmosphere remain unknown.
"PFTBA is just one example of
an industrial chemical that is
produced but there are no policies
that control its production, use or
emission," Hong said. "It is not
being regulated by any type of
climate policy."
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