A couple of research reviews
June 22, 2011
While our ability to describe and predict environmental change has come a long way in the past 30 years, there’s still much to learn and discuss. Scientists such as climate experts and ecologists are continually refining their understanding of their fields, and pushing the evolution of climate models alongside rapidly growing computational power. Even while the planning, designing and prototyping is occurring, NEON scientists find time to continue to contribute to increasing understanding in these areas. Two NEON scientists recently co-authored journal articles that describe approaches to incorporating two important missing pieces into climate models and predictions: carbon dioxide released from soils, and prehistoric concentrations of trace greenhouse gases. Atmospheric carbon dioxide seems to make all the headlines, but several times more carbon lurks in the slowly decaying organic matter in soils. Rising global temperatures could speed up the release of soil carbon into the atmosphere, but many current climate models don’t incorporate enough information to accurately depict how that might happen. Hank Loescher, head of NEON’s Fundamental Instrument Unit, teamed up with researchers from Oregon State University to find a way to more effectively describe how temperature variability affects the release of carbon from soils. They describe their efforts in an article in the Journal Biogeosciences, which garnered news coverage from Oregon State University, Science Daily, and Nature. Dr. Loescher and others are working to ensure that future data from NEON weather sensors and from air and soil sampling at each observatory site are able to help scientists better understand the detailed interplay between carbon, microbes and temperature. We have learned a lot about our past through climate science. The current episode of global warming isn’t the first time the Earth has gone through a major stretch of greenhouse warming. Periods of extreme warming 55 million years ago and 90 millions years ago are associated with extraordinary amounts of carbon dioxide in the atmosphere, just like modern warming. A thorough understanding of how the climate and Earth changed in those earlier greenhouse eras could help us get a better sense of what we’re in for in the next few centuries. For example, methane, nitrous oxide and ozone are lesser-known greenhouse gases that react with other components of the lower atmosphere and generate many times more heat-trapping power per ounce than carbon dioxide does. These three trace greenhouse gases likely played an important role in prehistoric global warming. But we don't currently have any physical records to tell us how much of the gases were present in Earth’s atmosphere so long ago. Andrew Fox, a NEON postdoctoral researcher and modeling expert from the University of Sheffield, worked with U.K. colleagues to fill some knowledge gaps about prehistoric climate. Fox and his collaborators spent months shuttling information between three computer models set up to describe climate-shaping processes during the warm periods 55 million years ago and 90 million years ago. They were able to back-calculate the amount and influence of methane, nitrous oxide and ozone in those prehistoric climates. Those three gases, it turns out, were much more prevalent and influential than anyone thought. More detailed results are recorded in the paper, which was published in the Proceedings of the National Academy of Sciences. The U.K. research team’s three-model approach takes into account the complex interactions between climate, vegetation and atmospheric chemistry. Dr. Fox is helping ensure NEON collects the data scientists need to help illuminate many such historical and interactions on a continental scale, and to test and refine further climate insights and predictions.