Carbon loss from soil accelerating climate change

Research published in Science today found that increased levels of carbon dioxide in the atmosphere cause soil microbes to produce more carbon dioxide, accelerating climate change.Two Northern Arizona University researchers led the study, which challenges previous understanding about how carbon accumulates in soil. Increased levels of CO2 accelerate plant growth, which causes more absorption of CO2 through photosynthesis.Until now, the accepted belief was that carbon is then stored in wood and soil for a long time, slowing climate change. Yet this new research suggests that the extra carbon provides fuel to microorganisms in the soil whose byproducts (such as CO2) are released into the atmosphere, contributing to climate change.”Our findings mean that nature is not as efficient in slowing global warming as we previously thought,” said Kees Jan van Groenigen, research fellow at the Center for Ecosystem Science and Society at NAU and lead author of the study. “By overlooking this effect of increased CO2 on soil microbes, models used by the Intergovernmental Panel on Climate Change may have overestimated the potential of soil to store carbon and mitigate the greenhouse effect.”In order to better understand how soil microbes respond to the changing atmosphere, the study’s authors utilized statistical techniques that compare data to models and test for general patterns across studies. They analyzed published results from 53 different experiments in forests, grasslands and agricultural fields around the world. These experiments all measured how extra CO2 in the atmosphere affects plant growth, microbial production of carbon dioxide, and the total amount of soil carbon at the end of the experiment.”We’ve long thought soils to be a stable, safe place to store carbon, but our results show soil carbon is not as stable as we previously thought,” said Bruce Hungate, director of the Center for Ecosystem Science and Society at NAU and study author. “We should not be complacent about continued subsidies from nature in slowing climate change.”Story Source:The above story is based on materials provided by Northern Arizona University. Note: Materials may be edited for content and length.

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Comet discovered hiding in plain sight: Near-Earth asteroid is really a comet

Sep. 10, 2013 — For 30 years, a large near-Earth asteroid wandered its lone, intrepid path, passing before the scrutinizing eyes of scientists while keeping something to itself: 3552 Don Quixote, whose journey stretches to the orbit of Jupiter, now appears to be a comet.The discovery resulted from an ongoing project led by researchers at Northern Arizona University using the Spitzer Space Telescope. Through a lot of focused attention and a little bit of luck, they found evidence of cometary activity that had evaded detection for three decades.”Its orbit resembled that of a comet, so people assumed it was a comet that had gotten rid of all its ice deposits,” said Michael Mommert, a post-doctoral researcher at NAU who was a Ph.D. student of professor Alan Harris at the German Aerospace Center (DLR) in Berlin at the time the work was carried out.What Mommert and an international team of researchers discovered, though, was that Don Quixote was not actually a dead comet — one that had shed the carbon dioxide and water that give comets their spectacular tails.Instead, the third-biggest near-Earth asteroid out there, skirting Earth with an erratic, extended orbit, is “sopping wet,” said NAU associate professor David Trilling. The implications have less to do with potential impact, which is extremely unlikely in this case, and more with “the origins of water on Earth,” Trilling said. Comets may be the source of at least some of it, and the amount on Don Quixote represents about 100 billion tons of water — roughly the same amount found in Lake Tahoe.Mommert said it’s surprising that Don Quixote hasn’t been depleted of all of its water, especially since researchers assumed that it had done so thousands of years ago. But finding evidence of CO2, and presumably water, wasn’t easy.During an observation of the object using Spitzer in August 2009, Mommert and Trilling found that it was far brighter than they expected. “The images were not as clean as we would like, so we set them aside,” Trilling said.Much later, though, Mommert prompted a closer look, and partners at the Harvard-Smithsonian Center for Astrophysics found something unusual when comparing infrared images of the object: something, that is, where an asteroid should have shown nothing. The “extended emission,” Mommert said, indicated that Don Quixote had a coma — a comet’s visible atmosphere — and a faint tail.Mommert said this discovery implies that carbon dioxide and water ice also might be present on other near-Earth objects.This study confirmed Don Quixote’s size and the low, comet-like reflectivity of its surface. Mommert is presenting the research team’s findings this week at the European Planetary Space Conference in London.

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Sideline teleconcussion robot to be tested at football games

Aug. 30, 2013 — There will be a new face at Northern Arizona University football games this fall — only this face will be on a robot on wheels.Mayo Clinic will be working with NAU to test the feasibility of using a telemedicine robot to assess athletes with suspected concussions during football games as part of a research study. With sophisticated robotic technology, use of a specialized remote controlled camera system allows patients to be “seen” by the neurology specialist, miles away, in real time. During the study, the robot equipped with a specialized camera system, remotely operated by a Mayo Clinic neurologist located in Phoenix who has the ability to assess a player for symptoms and signs of a concussion and to consult with sideline medical personnel.The first time the robot will be used in a game is this Friday, Aug. 30 when NAU kicks off its season against the University of Arizona in Tucson at 7 p.m. (MST).”Athletes at professional and collegiate levels have lobbied for access to neurologic expertise on the sideline. As we seek new and innovative ways to provide the highest level of concussion care and expertise, we hope that teleconcussion can meet this need and give athletes at all levels immediate access to concussion experts,” said Bert Vargas, M.D., a neurologist at Mayo Clinic who is heading up the research.This study would be the first to explore whether a remote neurological assessment is as accurate as a face-to-face evaluation in identifying concussion symptoms and making return to play decisions. Mayo Clinic physicians will not provide medical consultations during the study, they will only assess the feasibility of using the technology. If it appears feasible, this may open the door for countless schools, athletic teams, and organizations without access to specialized care to use similar portable technology for sideline assessments.”As nearly 60 percent of U.S. high schools do not have access to an athletic trainer, youth athletes, who are more susceptible to concussion and its after-effects, have the fewest safeguards in place to identify possible concussion signs and symptoms at the time of injury, Dr. …

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