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"Recognising ocean acidification in deep time: An evaluation of the evidence for acidification across the Triassic-Jurassic boundary Sarah E. GreeneCorresponding author contact information, 1, E-mail the corresponding author, Rowan C. Martindale1, E-mail the corresponding author, Kathleen A. Ritterbush E-mail the corresponding author, David J. Bottjer E-mail the corresponding author, Frank A. Corsetti E-mail the corresponding author, William M. Berelson E-mail the corresponding author Department of Earth Sciences, University of Southern California, Los Angeles, California, USA 90089 Received 22 July 2011. Accepted 17 March 2012. Available online 5 April 2012. While demonstrating ocean acidification in the modern is relatively straightforward (measure increase in atmospheric CO2 and corresponding ocean chemistry change), identifying palaeo-ocean acidification is problematic. The crux of this problem is that the rock record is a constructive archive while ocean acidification is essentially a destructive (and/or inhibitory) phenomenon. This is exacerbated in deep time without the benefit of a deep ocean record. Here, we discuss the feasibility of, and potential criteria for, identifying an acidification event in deep time. Furthermore, we investigate the evidence for ocean acidification during the Triassic-Jurassic (T-J) boundary interval, an excellent test case because 1) it occurs in deep time, beyond the reach of deep sea drilling coverage; 2) a potential trigger for acidification is known; and 3) it is associated with one of the 'Big Five' mass extinctions which disproportionately affected modern-style invertebrates. Three main criteria suggest that acidification may have occurred across the T-J transition. 1) The eruption of the Central Atlantic Magmatic Province (CAMP) and the associated massive and rapid release of CO2 coincident with the end-Triassic mass extinction provide a suitable trigger for an acidification event (

Abstract Changes in the upwelling and degassing of carbon from the Southern Ocean form one of the leading hypotheses for the cause of glacial-interglacial changes in atmospheric carbon dioxide. We present a 25,000-year-long Southern Ocean radiocarbon record reconstructed from deep-sea corals, which shows radiocarbon-depleted waters during the glacial period and through the early deglaciation. This depletion and associated deep stratification disappeared by ~14.6 ka (thousand years ago), consistent with the transfer of carbon from the deep ocean to the surface ocean and atmosphere via a Southern Ocean ventilation event. Given this evidence for carbon exchange in the Southern Ocean, we show that existing deep-ocean radiocarbon records from the glacial period are sufficiently depleted to explain the ~190 per mil drop in atmospheric radiocarbon between ~17 and 14.5 ka.

http://www.alaskafisheries.noaa.gov/newsreleases/2011/orangesubstance081811.pdf Alaska - NOAA determines "orange goo" in Alaska's Kivalina village is fungal spores The "orange goo" that washed ashore earlier this month in the remote Eskimo village of Kivalina along Alaska's northwest coast is fungal spores, not microscopic eggs as preliminary analysis indicated. Scientists at the NOAA Alaska Fisheries Science Center's Auke Bay Laboratory announced last week that the substance was biological in nature, rather than oil or pollution as originally thought by concerned residents of Kivalina. Per standard scientific procedure, samples were sent to NOAA's Analytical Response Team for a more thorough and detailed analysis and verification process. At NOAA's National Ocean Service Center for Coastal Environmental Health and Biomolecular Research, based in Charleston, S.C., a team of scientists highly-specialized and equipped to analyze microbiologic phenomena such as this determined that the substance is consistent with spores from a fungi that cause rust, a disease that infects only plants causing a rust-like appearance on leaves and stems. Rust fungi reproduce to infect other plants by releasing spores which disperse often times great distances by wind and water. However, whether this spore belongs to one of the 7,800 known species of rust fungi has not yet been determined. More information will be posted on the Alaska Fisheries Science Center website as it becomes available.

"Science 25 November 2011: Vol. 334 no. 6059 pp. 1052-1053 DOI: 10.1126/science.334.6059.1052 * News Focus Adaptation to Climate Change Adaptation to Climate Change Time to Adapt to a Warming World, But Where's the Science? 1. Richard A. Kerr With dangerous global warming seemingly inevitable, users of climate information-from water utilities to international aid workers-are turning to climate scientists for guidance. But usable knowledge is in short supply. Figure View larger version: * In this page * In a new window Adapt to that. Climate will change, but decision-makers want to know how, where, and when. "CREDIT: KOOS VAN DER LENDE/NEWSCOM" DENVER, COLORADO-The people who brought us the bad news about climate change are making an effort to help us figure out what to do about it. As climate scientists have shown, continuing to spew greenhouse gases into the atmosphere will surely bring sweeping changes to the world-changes that humans will find it difficult or impossible to adapt to. But beyond general warnings, there is another sort of vital climate research to be done, speakers told 1800 attendees at a meeting here last month. And so far, they warned, researchers have delivered precious little of the essential new science. At the meeting, subtitled "Climate Research in Service to Society,"* the new buzzword was "actionable": actionable science, actionable information, actionable knowledge. "There's an urgent need for actionable climate information based on sound science," said Ghassem Asrar, director of the World Climate Research Programme, the meeting's organizer based in Geneva, Switzerland. What's needed is not simply data but processed information that an engineer sizing a storm-water pipe to serve for the next 50 years or a farmer in Uganda considering irrigating his fields can use to make better decisions in a warming world. Researchers preparing for the next international climate assessment, due in 2013, delive

Nature has evolved efficient strategies to synthesize complex mineralized structures that exhibit exceptional damage tolerance. One such example is found in the hypermineralized hammer-like dactyl clubs of the stomatopods, a group of highly aggressive marine crustaceans. The dactyl clubs from one species, Odontodactylus scyllarus, exhibit an impressive set of characteristics adapted for surviving high-velocity impacts on the heavily mineralized prey on which they feed. Consisting of a multiphase composite of oriented crystalline hydroxyapatite and amorphous calcium phosphate and carbonate, in conjunction with a highly expanded helicoidal organization of the fibrillar chitinous organic matrix, these structures display several effective lines of defense against catastrophic failure during repetitive high-energy loading events.

Information Science Bounds and Vision Atlas of Science Visualizing What We Know by Katy Börner MIT Press, Cambridge, MA, 2010. 266 pp. $$29.95, £22.95. ISBN 9780262014458. 1. Mason A. Porter + Author Affiliations 1. The reviewer is at the Oxford Centre for Industrial and Applied Mathematics, Mathematical Institute, University of Oxford, Oxford OX1 3LB, UK, and at the CABDyN Complexity Centre and Somerville College, University of Oxford. 1. E-mail: porterm@maths.ox.ac.uk Visualization is a crucial but underappreciated part of science. As venues like the American Physical Society's Gallery of Fluid Motion and Gallery of Nonlinear Images illustrate every year, good visuals can make science more beautiful, more artistic, more tangible, and often more discernible. Katy Börner's continuing exhibition Places & Spaces: Mapping Science (1) and her book Atlas of Science: Visualizing What We Know arise from a similar spirit but are much more ambitious. Visualization is one of the most compelling aspects of science. Breathtaking visuals from sources like fractals and Disneyland's long-dead "Adventure Thru Inner Space" ride are what originally inspired me toward my personal scientific path, so I welcome any resource that promises to bring the visual joys of discovery to a wide audience. Importantly, Börner's exhibition and book are not mere artistic manifestations, although they would be impressive accomplishments even if that were her only goal. Some scientists have occasionally had great success in the visual arts; for example, physicist Eric Heller has long exhibited the gorgeous fruits of his research on quantum chaos and other topics (2). To fully appreciate Börner's efforts, however, one must be conscious that she is deeply concerned not just with visualization itself but with the science of visualization. Accordingly, her book discusses the history of the science of visualization, where it is now, and where she thinks it can go. Atlas of Scie

"Spatial diversity gradients are a pervasive feature of life on Earth. We examined a global ocean circulation, biogeochemistry, and ecosystem model that indicated a decrease in phytoplankton diversity with increasing latitude, consistent with observations of many marine and terrestrial taxa. In the modeled subpolar oceans, seasonal variability of the environment led to competitive exclusion of phytoplankton with slower growth rates and lower diversity. The relatively weak seasonality of the stable subtropical and tropical oceans in the global model enabled long exclusion time scales and prolonged coexistence of multiple phytoplankton with comparable fitness. Superimposed on the decline in diversity seen from equator to pole were "hot spots" of enhanced diversity in some regions of energetic ocean circulation, which reflected lateral dispersal. "