“This is ancient carbon, thousands and millions of years old.” It’s being released “much earlier than we thought.”
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| NASA’s Land Ocean Temperature Index (LOTI) data for April. CREDIT: NASA. |
The Alaskan tundra is warming so quickly it has become a net emitter of carbon dioxide ahead of schedule, a new study finds.
Since CO2 is the primary heat-trapping greenhouse gas — and since the permafrost contains twice as much carbon as the atmosphere does today — this means a vicious cycle has begun that will speed up global warming.
“Because
it’s getting warmer, there’s more CO2 coming out which means it’s going
to get warmer which means there’s more CO2 coming out,” explained
Harvard researcher and lead author Roisin Commane. “And it will just run away with itself.”
The study is the first to report
that a major portion of the Arctic is a net source of heat-trapping
emissions. As a result, Commane warns that our current climate models
need to be updated: “We’re seeing this much earlier than we thought we
would see it.”
“We find that Alaska, overall, was a net source of carbon to the atmosphere during 2012–2014,” the study concludes.
Data from NOAA’s Barrow Alaska station “indicate that October through
December emissions of CO2 from surrounding tundra increased by 73
percent since 1975, supporting the view that rising temperatures have
made Arctic ecosystems a net source of CO2.”
The permafrost,
or tundra, has been a very large carbon freezer. For a very long time,
it has had a very low decomposition rate for the carbon-rich plant
matter. But we’ve been leaving the freezer door wide open and are
witnessing the permafrost being transformed from a long-term carbon
locker to a short-term carbon un-locker.
“This is ancient carbon,” Dr. Commane told Alaska public radio. “The carbon that’s locked in the permafrost in the Arctic is thousands and millions of years old.”
Melting permafrost can release not just CO2, but also methane, a much stronger heat-trapping gas.
While most models that include melting permafrost look at CO2, Russian scientists have recently discovered
some 7,000 underground bubbles of permafrost-related methane in
Siberia. Since methane traps heat 86 times more effectively than CO2
over a 20-year span, these findings suggest that the effect of the
melting permafrost is even greater than first thought.
Also, a 2008 study, “Accelerated Arctic land warming and permafrost degradation during rapid sea ice loss,”
found that rapid sea ice loss — as has been experienced since the study
was published — could triple the rate of Arctic warming.
Meanwhile, the rapid Arctic warming that is fueling these emissions continues. On Monday, NASA reported
that April 2017 was the second-hottest April on record — only April
2016 was hotter. As the map above shows, Arctic temperatures were
blistering, up to 13.5°F (7.5°C) above the 1951–1980 average.
The
longer we delay aggressive climate action, the harder it will be to
stuff all the toothpaste back into the tube, and the more catastrophic
climate impacts we will face.
Links
- Earth’s melting permafrost threatens to unleash a dangerous climate feedback loop
- 7,000 massive methane gas bubbles under the Russian permafrost could explode anytime
- New York becomes latest state to take climate action into its own hands
- The Trump administration wants to freeze Obama’s signature climate policy indefinitely
- Trump just gutted U.S. policies to fight climate change
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