Methane is a greenhouse gas usually trapped as methane hydrate in sediment beneath the seabed. As temperatures rise, the hydrate breaks down and methane is released from the seabed, mostly dissolving into the seawater.
Most of the economic talk revolving around the melting Arctic refers to opportunity, such as Russia's plan to use the melted Arctic as a shipping route to speed natural gas and other resources to China. And the rogue petrostate Canada is considering shipping its tar sands crude over the Arctic to China and bypassing the beleaguered Keystone XL pipeline through the United States.
But the scientists, in research published this week in the journal Nature, said the cost of environmental and climate damage from the melting sea ice could far exceed any revenue from these new activities. The release of methane from thawing permafrost alone could cost the world $60 trillion, as countries are forced to deal with the ensuing extreme weather, health issues and lower agricultural production. Factoring in other impacts, such as ocean acidification, would likely raise the price tag even more.
The authors described the Arctic climate danger as an "economic time bomb."
"We calculate that the costs of a melting Arctic will be huge, because the region is pivotal to the functioning of Earth systems such as oceans and the climate," they wrote in the Nature article.