Climate change releases 1.7 billion tons of carbon dioxide per year from Arctic permafrost



The permafrost, which has been below 0 ° C for over two years, exists in Alaska and Siberia, accounting for approximately 20% of the northern hemisphere continent. It is reported that such permafrost is thawed by climate change and releases 1.7 billion tons of carbon dioxide annually.

Large loss of CO 2 in winter observed across the northern permafrost region | Nature Climate Change

Climate change has turned permafrost into a carbon emitter | CBC News

In Alaska and Siberia, 'continuous permafrost' that freezes continuously for more than two years has spread. However, there is a problem that the continuous permafrost is melting due to global warming. It has long been pointed out that melted permafrost releases large amounts of greenhouse gases such as carbon dioxide and methane due to decomposition of organic matter by microorganisms.

It turned out that the amount of carbon released by melting permafrost was more than expected, affecting the global warming countermeasures-GIGAZINE

So 75 scientists from dozens of institutions in 12 countries installed monitors to measure carbon dioxide at more than 100 locations in the Arctic Circle and performed more than 1000 measurements. It turned out that far more carbon dioxide was released in the Arctic than previously thought. The amount released is 1.7 billion tons per year , which is about twice the estimated value so far.

In the Arctic Circle, it becomes a midnight sun every summer, and the sun shines in the sky almost all day. Therefore, summer is a growing season for Arctic plants, and a large amount of carbon dioxide is absorbed. Nevertheless, the total absorption is over 1 billion tons, resulting in the release of 600 million tons of carbon dioxide per year .

According to Jocelyn Egan, a research member and environmental scientist at Dalhousie University , the amount of carbon dioxide released from permafrost and the amount of carbon absorbed by plants in the summer were almost balanced. . However, “We found that the amount of carbon dioxide released from permafrost in the winter is greater than the plants absorb in the growing season,” says Egan.

by Markus Trienke

According to the research team, the warming of permafrost continues, and carbon dioxide emissions tend to increase. It has been pointed out that carbon dioxide emissions may increase by 41% by the end of the 21st century if the pace at the time of writing the article is maintained. Even if efforts are made to stop global warming, emissions are reported to increase by at least 17%.

According to Mr. Egan, this research was limited to the measurement of the amount of carbon dioxide, and the amount of methane gas that has a greenhouse effect about 30 times that of carbon dioxide has not been measured.

in Science, Posted by log1i_yk