A new Cornell study, published online in Nature Geoscience, quantified the amount of black carbon in Australian soils and found that there was far more than expected, said Johannes Lehmann, the paper's lead author and a Cornell professor of biogeochemistry. The survey was the largest of black carbon ever published.
As a result of global warming, soils are expected to release more carbon dioxide, the major greenhouse gas, into the atmosphere, which, in turn, creates more warming. Climate models try to incorporate these increases of carbon dioxide from soils as the planet warms, but results vary greatly when realistic estimates of black carbon in soils are included in the predictions, the study found.
Soils include many forms of carbon, including organic carbon from leaf litter and vegetation and black carbon from the burning of organic matter. It takes a few years for organic carbon to decompose, as microbes eat it and convert it to carbon dioxide. But black carbon can take 1,000-2,000 years, on average, to convert to carbon dioxide.
By entering realistic estimates of stocks of black carbon in soil from two Australian savannas into a computer model that calculates carbon dioxide release from soil, the researchers found that carbon dioxide emissions from soils were reduced by about 20 percent over 100 years, as compared with simulations that did not take black carbon's long shelf life into account.
The findings are significant because soils are by far the world's largest source of carbon dioxide, producing 10 times more carbon dioxide each year than all the carbon dioxide emissions from human activities combined. Small changes in how carbon emissions from soils are estimated, therefore, can have a large impact.
"We know from measurements that climate change today is worse than people have predicted," said Lehmann. "But this particular aspect, black carbon's stability in soil, if incorporated in climate models, would actually decrease climate predictions."
The study quantified the amount of black carbon in 452 Australian soils across two savannas. Black carbon content varied widely, between zero and more than 80 percent, in soils across Australia.
"It's a mistake to look at soil as one blob of carbon," said Lehmann. "Rather, it has different chemical components with different characteristics. In this way, soil will interact differently to warming based on what's in it."
Blaine Friedlander | Newswise Science News
New Study Will Help Find the Best Locations for Thermal Power Stations in Iceland
19.01.2017 | University of Gothenburg
Water - as the underlying driver of the Earth’s carbon cycle
17.01.2017 | Max-Planck-Institut für Biogeochemie
An important step towards a completely new experimental access to quantum physics has been made at University of Konstanz. The team of scientists headed by...
Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...
Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.
While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...
Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales
Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...
Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.
As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...
19.01.2017 | Event News
10.01.2017 | Event News
09.01.2017 | Event News
20.01.2017 | Awards Funding
20.01.2017 | Materials Sciences
20.01.2017 | Life Sciences