Environment

Warming soil to release US-worth of carbon by mid-century

Warming soil to release US-wor...
Scientists say that the soil in the planet's colder regions holds great stocks of carbon
Scientists say that the soil in the planet's colder regions holds great stocks of carbon
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Scientists say that the soil in the planet's colder regions holds great stocks of carbon
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Scientists say that the soil in the planet's colder regions holds great stocks of carbon

There is a lot of talk about tipping points when it comes to climate change, alluding to a time in the not-so-distant future where the effects of human-induced global warming are no longer within our control. Melting ice caps and sea level rise are a couple of well-known examples of this, and a new study has revealed yet another way this whole thing could get away from us. Scientists studying carbon stored in the planet's soil have calculated that as temperatures rise, it will escape into the atmosphere in such quantities that it would be the same as adding another United States to the planet's carbon footprint by mid-century.

The stability of carbon stocks in the planet's soil in the face of rising temperatures has been the subject of some debate over the last few decades. But in the view of a team of Yale University researchers, earlier work in the area was painting an incomplete picture, with most of the attention focused on the world's temperate regions, which happen to hold much smaller stocks of carbon.

"Carbon stores are greatest in places like the Arctic and the sub-Arctic, where the soil is cold and often frozen," says study lead author Thomas Crowther. "In those conditions microbes are less active and so carbon has been allowed to build up over many centuries. But as you start to warm, the activities of those microbes increase, and that's when the losses start to happen. The scary thing is, these cold regions are the places that are expected to warm the most under climate change."

So as the temperatures rise and the soil becomes warmer, the carbon that has built up over thousands of years will be unlocked by increasingly busy microbes within.

The team arrived at these conclusions after analyzing raw data on carbon soil stocks collected through dozens of studies over the past 20 years. It predicts that for each degree Celsius of warming, around 30 petagrams of carbon will be ejected from the soil into the atmosphere (a petagram is one trillion kilograms). This is twice the amount emitted annually through human activities.

It is going to take our very best efforts to keep warming to 2° C, the threshold targeted through the Paris Agreement that we are currently well on track to surpass. But assuming best case scenario, the scientists predict that 2° C of warming will bring around 55 trillion kg of carbon out of the soil by mid-century, which makes for a 17 percent increase on projected emissions from human activity for the same period.

The scientists say this work helps to explain why there has been diverging opinions on the impact of carbon soil stocks over the preceding years, with studies indicating that some sites will undergo no change or even increase their capacity for carbon storage.

"The effects are strongly dependent on where you look," says Mark Bradford, professor of terrestrial ecosystem ecology at Yale. "Now that we know this, we can begin to develop more confidence in the idea that this biological feedback is real, and hence likely to accelerate human-induced climate change."

The team also points out that while it calculated the carbon losses likely to result from rising temperatures, there are other factors that could come into play. A recent NASA study showed that rising concentrations of carbon dioxide in the atmosphere are boosting Earth's vegetation coverage, and this is one example of something that could affect how quickly the carbon is released from the soil.

"Getting a handle on these kinds of feedbacks is essential if we're going to make meaningful projections about future climate conditions," said Crowther. "Only then can we generate realistic greenhouse gas emission targets that are effective at limiting climate change."

The research was published in the journal Nature.

Source: Yale University

12 comments
VincentWolf
Hopefully the world will rise 3 to 5 degrees by 2050 and the antarctic completely melts driving up oceans 200 feet and swamping all those idiots in congress that decry global warming is a hoax. And then redo workd maps so poor speculators can get rich buying land in middle of nowhere, usa
Helios
Climate change deniers in 3...and go!
Rann Xeroxx
Ha, I love how anyone who questions the underlying scientific method of Anthropogenic Global Warming (AGW) is smeared as a "denier" as if they are lumped into the same group of people denying the holocaust or something. Its a page right out of the liberal political handbook; name call, smear, scream and yell. Sorry but for science nothing is settled. Skeptics understand that climate changes but they are skeptical that human released CO2 is the driving force behind that change. Here are few links illustrating why there is a reason to think CO2 is not a major driver... https://wattsupwiththat.files.wordpress.com/2015/10/clip_image0044.jpg https://iceagenow.info/wp-content/uploads/2011/06/Easterbrook-Natural_global_warming.jpg
Bob Flint
We still think we are any threat or match for mother nature, dream on...
LordInsidious
Two links and claiming the science is not settled makes a denier. I wish those who don't like the results scientific community is producing had the courage to stop using all the results from the scientific community all together. This isn't a religion, you can't pick and choose the pieces that are agreeable or disagreeable and pretend to be anything other than denier of science. Prove the doubt scientifically or be a denier.
centaury11186
If some day happens that the earth warms up so much that it does not shelter life, we will be the only (stupid) species that contributed to its disappearance by distroying its own environment ...
toddzrx
Lord Insidious: hogwash. Science only benefits from a clash of opinions and vigorous debate. AGW theory would too if it hadn't become so politicized. Think about just this one fact for starters: none of the apocalyptic predictions of the Warmists have come true, not the temperature predictions, sea level rise, and so on. If the Warmists can't accurately predict what will happen in few years time, why should we believe their "science"?
milo
the major forces, some call them god, the deadly cosmic rays have increased 6%, the protective earth magnetic field, decreased 10%,
Bob
I don't deny global warming but I am very concerned about the attempts to increase government control and concentrate wealth to those who are attempting to dupe the public. The world is on a collision course with overpopulation, disease, famine and war in the coming generation. Global warming is the least of our worries. The earth will eventually self regulate with increased moisture in the warmer atmosphere. More snow toward the poles which will reflect more of the sun's rays. We should be right back into another ice age in a few years. No matter what we do about global warming a large portion of mankind will become extinct. We have become too civilized to survive. Perhaps a nuclear winter will speed things up.
Helios
There you have it. Argument by incredulity by those who would rather be right than change behaviors that have shown to be a large part of our state of affairs. You can either have a worldview that we have a pretty good understanding of science by now and therefor the mechanisms that create climate and weather on earth, or you can believe all of our technological advances are the result of sheer luck. It is indisputable fact that human activity has a detrimental effect on the natural environment and whether or not it is also the cause of climate change is irrelevant. It is happening. To those who think there are more pressing concerns such as war, famine and disease, those things will be hastened and exacerbated by climate change. The Pentagon says so ( and NASA, NOAA etc.) and is planning for that day. Further, to those who say the Earth's climate has been changing for millions of years, have you not seen the irony in that claim? How could we ever know the Earth is that old without the science that also says the excrement is going to hit the ventilator? Lastly, someone has been sitting in the echo chamber too long to make the claim that none of the predictions have come to pass. Florida mayors have signed on to press for action as a result of tidal flooding, the US government has begun relocating people in Louisiana and Alaska due to flooding and no ice, storms are getting stronger with less predictability ie. out of season and out of the ordinary (tornadoes in CA) extreme drought, extreme wildfires, extreme storm flooding.... ALL of these are predicted by climate change modelling. We can have more impact on energy use by simple conservation than waiting for green energy and government beuracrats. We need to start talking about zero population growth, changing how we grow food and how much we eat. These things aren't difficult problems to solve, only getting the masses to get on board.