https://www.independent.co.uk/environment/global-warming-greenhouse-gases-emissions-arctic-alaska-a8874456.html
[links and images in online article]
Emissions from thawing Arctic permafrost may be 12 times higher than
thought, scientists say
‘This needs to be taken more seriously than it is right now,’ says
author of new study
Chiara Giordano
April 17, 2019
Emissions from thawing Arctic permafrost may be 12 times higher than
previously thought, scientists have discovered.
Permafrost is a mix of soil, rock or sediment that has been frozen for
at least two years which is mostly found in the uppermost areas where
temperatures are rising more quickly than the rest of the world.
When it thaws because of global warming, it releases large quantities of
carbon dioxide and methane into the atmosphere, causing temperatures to
rise and creating a perpetual cycle where more permafrost melts.
Nitrous oxide, a third greenhouse gas nearly 300 times more potent than
carbon dioxide, stays in the atmosphere for an average of 114 years,
according to the Environmental Protection Agency (EPA).
It has “conventionally been assumed to have minimal emissions in
permafrost regions”, according to a fresh study published in the
Atmospheric Chemistry and Physics journal.
However the research team behind the study, led by Harvard University
scientists, has found that nitrous oxide emissions are 12 times higher
than previously thought and therefore more of a threat.
The group used a small plane with a probe on its nose to measure
greenhouse gases over 120sqm of thawing permafrost in the North Slope of
Alaska.
They found that nitrous oxide emissions reached what was previously
thought to be the expected yearly limit within just one month in August
2013.
Nitrous oxide also poses a second threat because “up in the
stratosphere, sunlight and oxygen team up to convert the gas into
nitrogen oxides, which eat at the ozone”, Harvard University said in a
statement.
Jordan Wilkerson, one of the authors of the study, said: “Much smaller
increases in nitrous oxide would entail the same kind of climate change
that a large plume of CO2 would cause.
“This is widespread, pretty high emissions.”
He called for further research on the greenhouse gases, especially
nitrous oxide, adding: “This needs to be taken more seriously than it is
right now.”
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