A melting Arctic is driving up carbon dioxide emissions, new US government report says

icemelt2 Polar ice melt. Credit: Shutterstock

The Arctic is undergoing a profound and rapid shift into a new condition, one that is greener, features less ice, warmer temperatures and which emits greenhouse gasses on par with several industrial nations due to melting permafrost, according to a new US government report released this week.

These changes will be felt far away from the North Pole in the form of more severe weather swings, increased greenhouse gas emissions and rising sea levels due to a thaw in Greenland’s ice sheet and melting mountain glaciers.

Such are the findings of the Arctic Report Card 2019, a major annual climate change assessment published by the National Oceanic and Atmospheric Administration in the United States. Its ominous conclusions show a region that is evolving into something chillingly unfamiliar.

At a time when the US presidential administration seeks to politicize climate change and dull the work of government agencies charting its effects, the report offers a striking and gloomy rebuke. It was only a few weeks ago that the White House threatened NOAA staff with reprisals for correcting a fabrication about hurricanes spread by President Trump.

Trump’s administration has meanwhile sought to withdraw the United States from the landmark 2015 Paris Climate Accord, under which nearly every nation on earth pledged to help keep global average temperature rises to 1.5 to 2 degrees Celsius by stemming greenhouse gases.

The UN climate talks currently taking place in Madrid, however, have made clear how unlikely that goal has become, as nations fail at making meaningful progress to dent their carbon emissions. In order to limit warming to Paris targets, the world’s nations would have to cut their planet-warming emissions in half by 2030, and become entirely carbon neutral by mid-century.

Even if industry, power and transport could be revolutionized in that short period, a melting Arctic could still put those temperature goals out of reach. That’s because the Arctic may already have become a net emitter of carbon dioxide due to thawing permafrost, which will accelerate global warming, the new report says.

Permafrost is the carbon-rich frozen soil that covers nearly a quarter of the Northern Hemisphere. It encompasses huge swathes of territory across Siberia, Alaska, Greenland and Canada. These frozen Arctic soils are thought to contain some 1,460 to 1,600 billion metric tons of organic carbon, which can be converted into the greenhouse gases of carbon dioxide and methane by microbes in soil. These microbes become more populous as temperatures warm. As a result, melting permafrost across the world’s northerly climates could release twice as many greenhouse gases as are already in the atmosphere.

The Arctic Report Card 2019 shows that this process may already underway, concluding that permafrost ecosystems could be releasing as much as 1.1 billion to 2.2 billion metric tons of carbon dioxide annually – making the Arctic as big an emitter as Japan on the lower end and Russia on the higher.

While there is still some uncertainty surrounding carbon emissions estimates, the Report Card warns that Arctic region – whose temperatures are climbing twice as fast as the rest of the world – could accelerate climate change.

A melting Arctic is of special concern to Siberia, where entire cities are built on foundations of permafrost. A recent Russian government report found that some 75,000 kilometers of oil pipelines are vulnerable to spills and ruptures should the ground melt beneath them. The same is true of Siberia’s highways and railroads, to say nothing of buildings, the foundations of which are expected to corrode and crumble as the ground thaws and softens.

The NOAA Report Card contained more bad news. Levels of Arctic sea ice continue to retreat, hitting the second lowest metric last year since scientist began keeping records. In the Bering Sea in particular, the Report Card says ice levels have been at record lows, comprising only about 30 percent of the mean levels between 1981 and 2010.

The warming temperatures are disrupting life for more than 70 indigenous communities that live around the Bering Sea. Hunting on the ice is becoming more hazardous and access to subsistence foods is shrinking, the report’s authors found. As the region warms, Arctic fish species are retreating to more northerly waters.

Charles Digges

charles@bellona.no