Melting Arctic permafrost will have $70tn climate impact

The release of methane and carbon dioxide from thawing permafrost will accelerate global warming and add up to $70 trillion to the worlds climate bill, according to the most advanced study yet of the economic consequences of a melting Arctic.

If countries fail to improve on their Paris agreement commitments, this feedback mechanism, combined with a loss of heat-deflecting white ice, will cause a near 5 per cent amplification of global warming and its associated costs, the Guardian quoted the study as saying which was published on Tuesday in Nature Communications.

The authors said that their study is the first to calculate the economic impact of permafrost melt and reduced albedo - a measure of how much light that hits a surface is reflected without being absorbed - based on the most advanced computer models of what is likely to happen in the Arctic as temperatures rise.

It shows how destabilised natural systems will worsen the problem caused by man-made emissions, making it more difficult and expensive to solve.

They assessed known stocks of frozen organic matter in the ground up to three metres deep at multiple points across the Arctic.

These were run through the world's most advanced simulation software in the US and at the UK Met Office to predict how much gas will be released at different levels of warming.

On the current trajectory of at least 3 Celsius of warming by the end of the century, melting permafrost is expected to discharge up to 280 gigatonnes of carbon dioxide and 3 gigatonnes of methane, which has a climate effect that is 10 to 20 times stronger than carbon dioxide.

This would increase the global climate-driven impacts by by $70 trillion between now and 2300.

"It's disheartening that we have this in front of us," said Dmitry Yumashev of Lancaster University.

"Even at 1.5 to 2 degrees Celsius, there are impacts and costs due to thawing permafrost. But they are considerably lower for these scenarios compared to business as usual. We have the technology and policy instruments to limit the warming but we are not moving fast enough."

--IANS

ksk