Most of the Earth’s carbon is trapped in the ground, and for centuries its existence has not been disturbed. But global warming which is also caused by carbon emissions can release carbon from the soil.
Another international study also conducted by the University of Exeter, UK, states that a temperature increase of 2 degrees Celsius causes the release of carbon into the air by 230 billion tons from all soil layers in the world.
Today the global soil contains two to three times more carbon than the atmosphere. An increase in temperature can accelerate decomposition reducing the amount of time carbon spends in the soil which is known as soil carbon turnover.
The study was designed to reveal the sensitivity of soil carbon turnover to global warming. The results of the research are expected to halve the uncertainty that has emerged so far and in the projections of future climate change.
“Our study ruled out the most extreme projections but nevertheless showed a substantial loss of soil carbon with a temperature increase of 2 degrees Celsius due to climate change, and this doesn’t even include the deeper loss of permafrost carbon,” said the co-authors. of the University of Exeter, Dr Sarah Chadburn.
Chadburn added, global warming creates a positive feedback effect, which creates a further warming effect. Thus soil carbon response to climate change is the area of greatest uncertainty in understanding the carbon cycle in climate change projections.
To address this, the researchers used a new combination of observational data and earth system models (ESM) that simulate climate and carbon cycles and then make predictions of climate change.
“We investigated how soil carbon is related to temperature at various locations on Earth to determine its sensitivity to global warming,” said lead author of the University of Exeter, Rebecca Varney, in the paper published in the journal Nature Communications.
Previous studies have shown that there is a release of 120 billion tons of carbon from the soil for every 2 degrees Celsius of warming. With the presence of the study, it has reduced this uncertainty to about 50 billion tons of carbon.
Co-author Professor Peter Cox of Exeter’s Global Systems Institute said that his study was not only useful in reducing uncertainty but also in determining carbon budgets.
“We have reduced this uncertainty in the climate change response, which is critical to calculating an accurate global carbon budget and successfully meeting the Paris Agreement targets,” he said. hi/I-1
