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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 (

"USC researcher experiments with changing ocean chemistry Jan. 19, 2011 | Molly Peterson | KPCC In his lab, USC's Dave Hutchins is simulating possible future atmospheres and temperatures for the Earth. He says he's trying to figure out how tiny organisms that form the base of the food web will react to a more carbon-intense ocean. Burning fossil fuels doesn't just put more carbon into the atmosphere and help warm the climate. It's also changing the chemistry of sea water. KPCC's Molly Peterson visits a University of Southern California researcher who studies the consequences of a more corrosive ocean. Tailpipes and refineries and smokestacks as far as the eye can see in Los Angeles symbolize the way people change the planet's climate. They remind Dave Hutchins that the ocean's changing too. Hutchins teaches marine biology at USC. He says about a third of all the carbon, or CO2, that people have pushed into earth's atmosphere ends up in sea water - "which is a good thing for us because if the ocean hadn't taken up that CO2 the greenhouse effect would be far more advanced than it is." He smiles. Hutchins says that carbon is probably not so good for the ocean. "The more carbon dioxide that enters the ocean the more acidic the ocean gets." On the pH scale, smaller numbers represent more acidity. The Monterey Bay Aquarium Research Institute estimates we've pumped 500 million tons of carbon into the world's oceans. Dave Hutchins at USC says that carbon has already lowered the pH value for sea water. "By the end of this century we are going to have increased the amount of acid in the ocean by maybe 200 percent over natural pre-industrial levels," he says. "So we are driving the chemistry of the ocean into new territory - into areas that it has never seen." Hutchins is one of dozens of scientists who study the ripples of that new chemistry into the marine ecosystem. Now for an aside. I make bubbly water at home with a soda machine, and to do that, I pump ca

A major puzzle of paleoclimatology is why, after a long interval of cooling climate, each late Quaternary ice age ended with a relatively short warming leg called a termination. We here offer a comprehensive hypothesis of how Earth emerged from the last global ice age. A prerequisite was the growth of very large Northern Hemisphere ice sheets, whose subsequent collapse created stadial conditions that disrupted global patterns of ocean and atmospheric circulation. The Southern Hemisphere westerlies shifted poleward during each northern stadial, producing pulses of ocean upwelling and warming that together accounted for much of the termination in the Southern Ocean and Antarctica. Rising atmospheric CO2 during southern upwelling pulses augmented warming during the last termination in both polar hemispheres.

December 18, 2012 The Ten Best Ocean Stories of 2012 | | | Share on redditReddit | Share on diggDigg | Share on stumbleuponStumble | Share on emailEmail | More Sharing ServicesMore Two market squids mating 2012 was a big year for squid science. Photo Credit: © Brian Skerry, www.brianskerry.com Despite covering 70 percent of the earth's surface, the ocean doesn't often make it into the news. But when it does, it makes quite a splash (so to speak). Here are the top ten ocean stories we couldn't stop talking about this year, in no particular order. Add your own in the comments! 2012: The Year of the Squid From the giant squid's giant eyes (the better to see predatory sperm whales, my dear), to the vampire squid's eerie diet of remains and feces, the strange adaptations and behavior of these cephalopods amazed us all year. Scientists found a deep-sea squid that dismembers its own glowing arm to distract predators and make a daring escape. But fascinating findings weren't relegated to the deep: at the surface, some squids will rocket themselves above the waves to fly long distances at top speeds. James Cameron Explores the Deep Sea Filmmaker James Cameron has never shied away from marine movie plots (See: Titanic, The Abyss), but this year he showed he was truly fearless, becoming the first person to hit the deepest point on the seafloor (35,804 feet) in a solo submarine. While he only managed to bring up a single mud sample from the deepest region, he found thriving biodiversity in the other deep-sea areas his expedition explored, including giant versions of organisms found in shallow water. Schooling sardines form a "bait ball." Small fish, such as these schooling sardines, received well-deserved attention for being an important part of the food chain in 2012. Photo Credit: © Erwin Poliakoff, Flickr Small Fish Make a Big Impact Forage fish-small, schooling fish that are gulped down by predators-should be left in the ocean for larger fish, marin

Science 25 November 2011: Vol. 334 no. 6059 p. 1039 DOI: 10.1126/science.334.6059.1039-b * News of the Week Random Sample Mongolia's 'Ice Shield' Figure View larger version: * In this page * In a new window Hot zone. Flanked by desert, Ulan Bator will be cooled in summer by an "ice shield." "CREDIT: BRÜCKE-OSTEUROPA/WIKIPEDIA" As the coldest capital on Earth, you might think the last thing Ulan Bator needs is more ice. But that is just what it's about to get under a geoengineering trial aimed at "storing" freezing winter temperatures to cool and water the city during the summer. At the end of this month, engineers will drill a series of bores through the ice on the Tuul River, pump up water from below, and spray it on the surface where it will freeze. This process will be repeated throughout the winter, adding layer after layer to create a chunk of ice that will be 7 or 8 meters thick by the spring. It's an attempt to artificially create the ultra-thick slabs-known as naleds in Russian-that occur naturally in far northern climes when rivers or springs push through surface cracks. Nomads have long made their summer camps near such phenomena, which melt much later than normal ice. Flanked by desert and plagued by summer temperatures that can rise close to 40°C, Ulan Bator's municipal government hopes the $724,000 experiment will create a cool microclimate and provide fresh water as the naled melts. ECOS & EMI, the Anglo-Mongolian company behind the plan, has still greater ambitions. "Everyone is panicking about melting glaciers and icecaps, but nobody has yet found a cheap, environmentally friendly alternative," says Robin Grayson, a geologist in Ulan Bator for ECOS & EMI. "If you know how to manipulate them, naled ice shields can repair permafrost and build cool parks in cities." The process, Grayson says, can be replicated anywhere where winter temperatures fall below −5°C for at least a couple of months.

Ocean Probes To Help Refine Climate Change Forecasting; 'Oceanography Is Risky; You Lose Things' by Underwatertimes.com News Service - August 5, 2011 17:43 EST LOS ANGELES, California -- A USC researcher has opened a new window to understanding how the ocean impacts climate change. Lisa Collins, environmental studies lecturer with the USC Dornsife College, spent four years collecting samples from floating sediment traps in the San Pedro Basin off the Los Angeles coast, giving scientists a peek at how much carbon is locked up in the ocean and where it comes from. Collins' research suggests that the majority of particulate organic carbon (POC) falling to the basin floor is marine-derived, not the result of runoff from rainfall. This means that the ocean off the coast of Southern California is acting as a carbon "sink" - taking carbon out of the atmosphere via phytoplankton and locking it up in sediment. Though estimates regarding the effect of carbon in the ocean already exist, her hard data can help climatologists create more accurate predictions of how carbon will impact global warming. What is unique about Collins' study is that it is not just a snapshot of POC falling, but rather a finely detailed record of four years of POC production, showing how much fell and when. "It's all tied to climate change," said Collins, who started the research as a graduate student working for USC Earth Sciences Professor Will Berelson. "This lets us see patterns. "Our data can help climate modelers better predict the interactions between the oceans and atmosphere with respect to carbon which can help them better predict how much carbon dioxide will end up sequestered over the long term as sediments in the ocean," she said. Collins' study is among the longest of its kind in the region. A similar study was conducted in Santa Monica Basin from 1985-1991, and another is currently underway in Hawaii. Her findings appear in the August issue of Deep-Sea Research I. Between Janua

LIFEONTERRA is a collaborative filmspace and laboratory exploring the questions and ideas on the cutting-edge of science and at the farthest horizons of the natural world. The "TERRA: The Nature of Our World" video podcast launched in October 2005. TERRA films have been downloaded over one million times. LIFEONTERRA is committed to keeping ALL content free & easily accessible in perpetuity. To this end, we host past & present content in a digital archive. All our shows are available as a Medium Quality Flash 8 or High Quality Quicktime (.m4v) . This is a permanent resource for everyone: fans, educators, students, and anyone who is simply curious about the natural world. We are a worldwide crossroads, a forum for compelling issues, and a stage for the awesome diversity of our planet.

Science 8 July 2011: Vol. 333 no. 6039 pp. 173-175 Galaxy Zoo Volunteers Share Pain and Glory of Research 1. Daniel Clery A project to "crowdsource" galactic classifications has paid off in ways the astronomers who started it never expected. Figure View larger version: * In this page * In a new window Space oddity. Greenish "voorwerp" spotted by a Dutch volunteer still intrigues scientists. "CREDIT: NASA, ESA, W. KEEL (UNIVERSITY OF ALABAMA), AND THE GALAXY ZOO TEAM" The automated surveys that are becoming increasingly common in astronomy are producing an embarrassment of riches for researchers. Projects such as the Sloan Digital Sky Survey (SDSS) are generating so much data that, in some cases, astronomers don't know what to do with them all. SDSS has compiled a list of more than 1 million galaxies. To glean information about galaxy evolution, however, astronomers need to know what type of galaxy each one is: spiral, barred spiral, elliptical, or something else. At present, the only reliable way to classify galaxies is to look at each one. But the SDSS list is so long that all the world's astronomers working together couldn't muster enough eyeballs for the task. Enter the "wisdom of crowds." An online effort called Galaxy Zoo, launched in 2007, set a standard for citizen-scientist participation projects. Zealous volunteers astonished the project's organizers by classifying the entire catalog years ahead of schedule. The results have brought real statistical rigor to a field used to samples too small to support firm conclusions. But that's not all. Buoyed by the curiosity and dedication of the volunteers, the Galaxy Zoo team went on to ask more-complicated classification questions that led to studies they hadn't thought possible. And in an online discussion forum on the Galaxy Zoo Web site, volunteers have pointed to anomalies that on closer inspection have turned out to be genuinely new astronomical objects. "I'm incredibly impres

Isles of Abundance Britain has taken another step toward designating the world's largest marine reserve around the Chagos Islands, a group of 55 coral protrusions in the Indian Ocean. The government announced the end of a 4-month public comment period on 5 March and is expected to reach a final decision by May. The Chagos contain half of the Indian Ocean's remaining healthy reefs. The waters are said to be among the cleanest on Earth, allowing corals to grow in deep water less vulnerable to global warming. The islands are located in the equatorial "tuna belt," which hosts what a Royal Zoological Society of London report called one of the "most exploited, badly enforced fisheries in the world." A total ban on fishing in the 544,000-square-kilometer zone, an area the size of France, would make it an even larger protected area than the current record-holder, the 360,000-km2 Papahanaumokuakea Marine National Monument in the northwestern Hawaiian Islands. The Pew Environment Group has spearheaded a 3-year campaign for creation of a Chagos reserve. It would be "literally an island of abundance in a sea of depletion," says Pew's Jay Nelson. The islands are uninhabited except for the U.S. Navy base on Diego Garcia. Some 1500 Chagossians were deported to Mauritius in the 1970s for military security.