Sub-Arctic wasteland is a ‘climate time-bomb’ that could be worse than previously thought

FROZEN, sub-Arctic wastelands loaded with planet-heating greenhouse gases are more susceptible to global warming than previously understood, scientists warned on Monday.

Even stabilising the world’s climate at 2C above pre-industrial levels — the daunting goal laid down in the 196-nation Paris Agreement — would melt more than 40 per cent of permafrost, or an area nearly twice the size of India, they reported in the journal Nature Climate Change.

That could take centuries or longer, but would eventually drive up global temperatures even further as more gases escaped into the air.

Sometimes called a climate change time bomb, the northern hemisphere’s 15 million square kilometres of increasingly misnamed permafrost contains roughly twice as much carbon — mainly in the form of methane and carbon dioxide (CO2) — as Earth’s atmosphere.

Currently, the atmosphere holds about 400 parts per million of CO2, 30 per cent more than when warming caused by human activity started in the mid-19th century.

“We estimate that four million square kilometres — give or take a million — will disappear for every additional degree of warming,” said co-author Sebastian Westermann, a senior lecturer at the University of Oslo.

“That’s about 20 per cent higher than previous estimates,” he said…

Source: Permafrost: Sub-Arctic wasteland is a ‘climate time-bomb’ that could be worse than previously thought | Perth Now