Carbon emissions from warming soils could trigger disastrous feedback loop

Carbon emissions from warming soils could trigger disastrous feedback loop

SOURCE: The Guardian and Washington Post DATE: October 5, 2017 SNIP: Warming soils are releasing more carbon into the atmosphere than previously thought, suggesting a potentially disastrous feedback mechanism whereby increases in global temperatures will trigger massive new carbon releases in a cycle that may be impossible to break. The increased production of carbon comes from the microbes within soils, according to a report in the peer-review journal Science, published on Friday. The 26-year study is one of the biggest of its kind, and is a groundbreaking addition to our scant knowledge of exactly how warming will affect natural systems. Potential feedback loops, or tipping points, have long been suspected to exist by scientists, and there is some evidence for them in the geological record. What appears to happen is that once warming reaches a certain point, these natural biological factors kick in and can lead to a runaway, and potentially unstoppable, increase in...
How frozen farmers’ fields are an unexpected culprit in climate change, according to a new study

How frozen farmers’ fields are an unexpected culprit in climate change, according to a new study

SOURCE: National Post DATE: April 11, 2017 SNIP: Across Canada, the last of the snow and ice is melting away from a vast expanse of farmers’ fields, making way for the planting of this year’s crops. And — suggests a new Canadian study — making an unexpectedly large contribution to greenhouse gases and climate change. Strange as it might seem, the thawing of frozen cropland burps nitrous oxide into the atmosphere at rates far greater than previously thought, meaning agriculture’s role in producing the greenhouse gas has been greatly underestimated, according to research from the Universities of Guelph and Manitoba. Nitrous oxide — commonly known as laughing gas and used as a dental anesthetic — accounts for well under 10 per cent of greenhouse gas emissions. But it’s almost 300 times as potent as carbon dioxide at trapping energy, the greenhouse effect believed to be warming the...
Soils could release much more carbon than expected as climate warms

Soils could release much more carbon than expected as climate warms

SOURCE: Phys.org DATE: March 9, 2017 SNIP: Soils could release much more CO2 than expected into the atmosphere as the climate warms, according to new research by scientists from the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab). Their findings are based on a field experiment that, for the first time, explored what happens to organic carbon trapped in soil when all soil layers are warmed, which in this case extend to a depth of 100 centimeters. The scientists discovered that warming both the surface and deeper soil layers at three experimental plots increased the plots’ annual release of CO2 by 34 to 37 percent over non-warmed soil. Much of the CO2 originated from deeper layers, indicating that deeper stores of carbon are more sensitive to warming than previously thought. Experts estimate soils below 20 centimeters in depth contain more than 50 percent of the planet’s stock of soil organic carbon. The big questions have been: to what extent do the deeper soil layers respond to warming? And what does this mean for the release of CO2 into the atmosphere? “We found the response is quite significant,” says Caitlin Hicks Pries, a postdoctoral researcher in Berkeley Lab’s Climate and Ecosystem Sciences Division. She conducted the research with co-corresponding author Margaret Torn, and Christina Castahna and Rachel Porras, who are also Berkeley Lab scientists. “If our findings are applied to soils around the globe that are similar to what we studied, meaning soils that are not frozen or saturated, our calculations suggest that by 2100 the warming of deeper soil layers could cause a release of carbon to the...
More dire data, less climate change concern?

More dire data, less climate change concern?

SOURCE: Deutsche Welle DATE: Dec 10, 2016 SNIP: With Trump poised to dismantle US climate action, is this a sign of public burnout on the climate topic? Although European voters have indicated they see climate change as a more important factor in their voting than Americans, a similar trend is present: less importance attached to the climate change issue in the face of more short-term fears – such as terrorism, immigration and perhaps imminent geopolitical conflict. But even as climate change recedes from the spotlight, recent evidence shows that the situation is perhaps even more dire than originally thought: Two alarming new studies released over the past month have scientists worried. This week, the Colorado-based National Snow and Ice Data Center revealed that both the Arctic and Antarctic experienced record lows in sea ice extent in November – astonishing scientists who say it is unprecedented for sea ice to retreat at a time when the Arctic enters the coldest, darkest part of the year. The news has policymakers worried as well. “This news from the Arctic might be the start of a tipping point that we must avoid, because this would mean that we as human beings are losing control,” said Gerben-Jan Gerbrandy, a Dutch Liberal member of the European Parliament, at an event this week. … Last week, the Yale School of Forestry and Environmental Studies revealed alarming new research showing that the long-theorized “feedback loop” of climate change and soil carbon loss is indeed a real phenomenon – meaning that the rate of global temperature could rise much faster than expected. Thomas Crowther, who conducted the research,...
Soil’s potential to soak up planet-warning carbon dioxide has been overestimated by as much as 40%, say scientists

Soil’s potential to soak up planet-warning carbon dioxide has been overestimated by as much as 40%, say scientists

SOURCE: The Guardian DATE: September 22, 2016 SNIP: Hopes that large amounts of planet-warming carbon dioxide could be buried in soils appear to be grossly misplaced, with new research finding that the ground will soak up far less carbon over the coming century than previously thought. Radiocarbon dating of soils, when combined with previous models of carbon uptake, has shown the widely assumed potential for carbon sequestration to combat climate change has been overestimated by as much as 40%. This means it will take hundreds or even thousands of years for soils to soak up large amounts of the extra CO2 pumped into the atmosphere by human activity – far too long to be relied upon as a way to help the world avoid dangerous global warming this...