Arctic & Antarctica
Wikimedia Commons, File: Climate Impacts to Arctic Coasts (32682616471).jpg / Benjamin Jones, U.S. Geological Survey

A warming Arctic could cost the world trillions of dollars

New science warns that melting ice and permafrost could set off feedback loops that make climate change worse

SCIENTISTS HAVE LONG warned that climate change is likely to bring expensive impacts, from rising seas to stronger storms. And a new study comes with a hefty price tag.

A warming Arctic is shifting from white to dark as sea ice melts and land-covered snow retreats, and that means it can absorb even more of the sun’s heat. Plus, the Arctic’s vast permafrost area is thawing, releasing more heat-trapping carbon and methane. These climate-change-driven feedbacks in the Arctic are accelerating warming even faster and may add nearly $70 trillion to the overall costs of climate change—even if the world meets the Paris Agreement climate targets, a new study says.

However, if efforts can be made to keep climate change limited to 2.7 degrees Fahrenheit (1.5C), the extra cost of Arctic warming drops to $25 trillion, new research published in Nature Communications reports. A trillion is a thousand billion. For comparison, the global GDP in 2016 was around $76 trillion.

“Massive changes are underway in the Arctic. Permafrost and loss of sea ice and snow are two known tipping elements in the climate system,” said lead author Dmitry Yumashev of the Pentland Centre for Sustainability in Business, Lancaster University in the United Kingdom.

“We wanted to know what Arctic warming could do to the rest of the world,” said Yumashev.

Climate “tipping elements” are also known as tipping points or feedbacks, where a change in a natural system triggers further warming. Last year, a study documented ten tipping points and noted that these can act like a row of dominoes, one pushing another system over. Once started, these tipping points are nearly impossible to stop and risk what researchers called a “Hothouse Earth” state—in which the global average temperature is 4 to 5 degrees Celsius higher, with regions like the Arctic averaging 10 degrees C higher than today.

The Arctic is warming at least twice as fast as the global average. Sea ice has been in decline since the 1990s, exposing a million square miles of ocean. As more solar energy is absorbed it creates what’s called the surface albedo feedback.

Melting permafrost

Permafrost feedback involves the frozen soils of the permafrost zone that cover nearly a quarter of the land area of the northern hemisphere. These soils, which contain enormous stores of carbon and methane, have been thawing since the 1980s. As Arctic temperatures climb, thawing permafrost releases those warming gases.

The Yumashev study uses the most updated estimates of these feedbacks, which have yet to be included in climate models or carbon budgets. It turns out that permafrost and loss of albedo will cause significant extra warming globally, even if the world meets the 1.5°C and 2°C Paris Agreement targets, the research suggests. This extra warming could result in additional temperature-driven impacts on the economy, ecosystems, and human health, and additional impacts from sea-level rise.

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