Science

Study: Permafrost melt is releasing TWICE as much carbon than once thought, driving climate change


Permafrost melt is releasing TWICE as much carbon than previously thought and turning Arctic tundra into a climate change contributor, says new study

  • A report says Arctic permafrost is releasing 1.7 billion tons of carbon per year
  • That’s double the permafrost emission levels previously recorded
  • Plants thought to mitigate emissions are failing to keep pace, scientists say 
  • Permafrost emissions are projected to rise by 41 percent over the next century

A combination of rapid permafrost melt and lack of carbon absorption is turning swaths of Arctic tundra into a hotbed for CO2 emissions, says a new report.  

A study carried out by 75 scientists in 12 countries and published in Nature Climate Change finds that levels of carbon released by permafrost melt are twice as high as previously thought and are outpacing the ability of tundra plants to absorb it. 

More than 100 sensors planted in various locations across the Arctic show permafrost is releasing 1.7 billion tons of carbon into the atmosphere while Arctic plants – long thought to offset that release by absorbing emissions in the summer – are absorbing just 1 billion tons.

Scientists have been keying in on permafrost erosion like the kind seen above and now have evidence that the melt is releasing twice as much carbon into the atmosphere than previously thought

Scientists have been keying in on permafrost erosion like the kind seen above and now have evidence that the melt is releasing twice as much carbon into the atmosphere than previously thought

This is the first proof that tundra permafrost melt is now a net contributor to greenhouse gas emissions and a harbinger of increasingly adverse conditions in the region. 

‘There’s a net loss,’ Dalhousie University’s Jocelyn Egan, one of 75 co-authors of a paper published in Nature Climate Change told CBC.

‘In a given year, more carbon is being lost than what is being taken in. It is happening already.’   

The international study realigns popular scientific thought on Arctic permafrost melt which posited that Arctic plants mostly mitigated carbon emitted during the winter when they flourished in the summer.

Not only are the plants failing to absorb carbon, but according to scientists, the pace of emissions is likely to increase. 

Projections show that if global emissions remains static, that melting permafrost, which has long sealed-in carbon rich soil, may release 41 percent more carbon by the end of the decade.

As glaciers retract, they expose permafrost that has stored deep sinks of carbon. As that ice warms it releases greenhouse gases into the atmosphere and exacerbates climate change

As glaciers retract, they expose permafrost that has stored deep sinks of carbon. As that ice warms it releases greenhouse gases into the atmosphere and exacerbates climate change

Most projections show the world has failed to meet benchmarks for curbing emissions outlined by accords like the Paris Agreement. 

Projections foreshadow a disconcerting future for an already-embattled Arctic.

Earlier this summer about 90 percent of the surface of Greenland’s ice sheet melted between July 30 and August 2, during which time an estimated 55 billion tons of ice poured off the island and into the ocean, according to the National Snow and Ice Data Center. 

To help mitigate surface melt and its subsequent contributions to sea level rise, scientists have proposed increasingly elaborate solutions like using glass beads to reflect sun.

WHAT IS PERMAFROST AND WHAT HAPPENS IF IT MELTS?

Permafrost is a permanently frozen layer below the Earth’s surface found in Arctic regions such as Alaska, Siberia and Canada.

It typically consists of soil, gravel and sand bound together by ice, and is classified as ground that has remained below 0°C (32°F) for at least two years.

It is estimated 1,500 billion tons of carbon is stored in the world’s permafrost – more than twice the amount found in the atmosphere.

The carbon comes in the form of ancient vegetation and soil that has remained frozen for millennia.

If global warming were to melt the world’s permafrost, it could release thousands of tonnes of carbon dioxide and methane into the atmosphere. 

Because some permafrost regions have stayed frozen for thousands of years, it is of particular interest for scientists.

Ancient remains found in permafrost are among the most complete ever found because the ice stops organic matter from decomposing.

A number of 2,500-year-old bodies buried in Siberia by a group of nomads known as the Scythians have been found with their tattooed skin still intact.

A baby mammoth corpse uncovered on Russia’s Arctic coast in 2010 still sported clumps of its hair despite being more than 39,000 years old.

Permafrost is also used in the study of Earth’s geological history as soil and minerals buried deep in Arctic regions for thousands of years can be dug up and studied today.

 



READ SOURCE

Leave a Reply

This website uses cookies. By continuing to use this site, you accept our use of cookies.