Global soil carbon losses in response to warming

In a recent study published in Nature, 50 researchers from around the world confirm the concerns that they have had for a long time: soils will release a large amount of carbon in response to the rising air temperature.

The study is a summary of 49 empirical studies that have investigated carbon emissions from the soil in different places around the world. Although the results varied slightly from area to area, the team saw a pattern in which the carbon losses were higher in those regions that have had the largest rise in temperature so far. The largest losses of carbon were seen in the Arctic areas where the soil is warming up rapidly and is quite deep. They also saw high losses along the mid-latitude areas. The study only considered the upper layers of soil, and if the soil turns out to release carbon from the deeper permafrost layer, emissions could be even more devastating.

The researchers believe that if we continue with a “business-as-usual” scenario, the soil will release 200 billion tons of carbon dioxide by the year 2050. Even if the planet’s vegetation can reclaim some of this carbon, it will not compensate for the losses that have occurred.

Source: The Washington post, 30 November, 2016. Scientists have long feared this ‘feedback’ to the climate system. Now they say it’s happening.



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