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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.

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.

"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 (

Key Findings Current Coastal Management Challenges Current coastal management challenges are worsening. Top management challenges will be exacerbated by climate change. Current management challenges make adaptation planning and decision-making difficult. Climate Change Concerns, Knowledge, and Actions Attitudes and knowledge about climate change are strongly supportive of adaptation action. Attention to adaptation has increased markedly over the past five years. Adaptation planning and implementation is still in the very early stages. There is limited familiarity with innovative adaptation approaches. Information, Technical Assistance, and Training Needs Organizational missions, job responsibilities, and legal requirements shape common information use. Ease of access to information is the overriding determinant of information use. Specific information needs differ by professional group. Critical opportunities exist to meet coastal professionals' information, technical assistance, and training needs Survey Background Decision-makers in California's (CA) coastal counties recognize that climate change will impact their communities and coastline. Yet, coastal CA communities are at different stages in developing and/or implementing climate change adaptation plans. During the Summer of 2012, USC Sea Grant, in partnership with 14 other CA-based organizations (listed below), launched a survey to understand the needs and barriers coastal communities have in planning for climate change in order to develop appropriate trainings and technical assistance for communities and determine the best way to link communities to resources and tools already available. Survey Partners USC Sea Grant California Sea Grant Center for Ocean Solutions, Stanford University California Nevada Applications Program (CNAP) at the Scripps Institution of Oceanography, University of California, San Diego through the NOAA Regional Integrat

Science 3 February 2012: Vol. 335 no. 6068 pp. 520-521 DOI: 10.1126/science.335.6068.520 News Focus Ecology Rebuilding Wetlands by Managing the Muddy Mississippi Carolyn Gramling Coastal managers and scientists have struggled to find ways to restore water flow through the wetlands of the Mississippi delta and bring back the sediment, supply of which has been cut in half by humanmade river channels, levees, and dams intended to control the river and save coastal communities from flooding. The U.S. Army Corps of Engineers opened the Morganza spillway during the 2011 Mississippi River floods to divert floodwaters, which offered a rare opportunity to conduct a large-scale natural experiment in real time. The floodwaters did carry enough sediment to help rebuild the wetlands, but that material didn't always stay where it could do the most good. However, researchers gained valuable insights-including ideas about how spillway design can help produce more targeted sediment deposits, and what volume of flow through the spillways might be required for effective wetland rebuilding.

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.

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.

"Time lapse footage taken by Oregon State University alum Don Pettit during his time on the International Space Station. This one shows Earth from day to night. Watch the other eight time lapse videos from space http://www.youtube.com/view_play_list... science"

"Multilingualism-the ability to understand and speak several languages-is exceptional in the United States but common elsewhere, especially in small-scale traditional societies. For instance, once while I was camped with some New Guinea Highlanders conversing simultaneously in several local languages, I asked each man to name each language in which he could converse. It turned out that everyone present spoke at least 5 languages, and the champion was a man who spoke 15. What are the cognitive effects of such multilingualism? Recent studies (1-5) show that children raised bilingually develop a specific type of cognitive benefit during infancy, and that bilingualism offers some protection against symptoms of Alzheimer's dementia in old people. "

During this week of action, OCEAN2012 member groups are inviting EU citizens to witness the impact overfishing has had on the marine environment and learn how the EU's CFP reform is an opportunity to go back to the future.

"What are the impacts of ocean acidification on key benthic (seabed) ecosystems, communities, habitats, species and their life cycles? The average acidity (pH) of the world's oceans has been stable for the last 25 million years. However, the oceans are now absorbing so much man made CO2 from the atmosphere that measurable changes in seawater pH and carbonate chemistry can be seen. It is predicted that this could affect the basic biological functions of many marine organisms. This in turn could have implications for the survival of populations and communities, as well as the maintenance of biodiversity and ecosystem function. In the seas around the UK, the habitats that make up the seafloor, along with the animals associated with them, play a crucial role in maintaining a healthy and productive marine ecosystem. This is important considering 40% of the world's population lives within 100km of the coast and many of these people depend on coastal systems for food, economic prosperity and well-being. Given that coastal habitats also harbour incredibly high levels of biodiversity, any environmental change that affects these important ecosystems could have substantial environmental and economical impacts. During several recent international meetings scientific experts have concluded that new research is urgently needed. In particular we need long-term studies that determine: which organisms are likely to be tolerant to high CO2 and which are vulnerable; whether organisms will have time to adapt or acclimatise to this rapid environmental change; and how the interactions between individuals that determine ecosystem structure will be affected. This current lack of understanding is a major problem as ocean acidification is a rapidly evolving management issue and, with an insufficient knowledge base, policy makers and managers are struggling to formulate effective strategies to sustain and protect the marine environment in the face of ocean acidification."

Webcast: 'We Sea Change,' a Climate Change Education Video 0 What is climate change, and how is it affecting coastal Carolina? That is the question that a group of teens from Isaac Bear Early College High School set out to answer for their Third National Student Summit on the Ocean & Coasts project. Representing the North Carolina Aquarium at Fort Fisher, four teens spent months researching climate change issues such as salt water intrusion in rivers, changes to barrier islands, disappearing beaches, and habitat loss in longleaf pine forests in the Wilmington, N.C., region. The students presented a video documenting this research during the National Student Summit on February 15, 2011 at the Smithsonian's National Museum of Natural History. After the Summit, the team broadened the project's scope to include climate change education through the production of a second video. This film, We Sea Change, aims to give their local community in Wilmington an understanding of climate change, impacts on the coastal Carolina region, and how people can be part of the climate change solution. We Sea Change will be broadcast live to the Ocean Portal from the North Carolina Aquarium at Fort Fisher on Wednesday, September 28, 2011 at 7pm. There will be a panel discussion on climate change immediately following the 7pm screening. Meet the team! The Cape Fear Beach Bears: Sandy Paws for a Cause team members include students Jessica Lama, Keela Sweeney, Evan Lucas, and Dustin Chambers. They have conducted research and produced their videos under the guidance of teachers Bryan Bishop from Isaac Bear Early College High School and Megan Ennes from the North Carolina Aquarium at Fort Fisher.

Aerosols Altered Asian Monsoons Summer monsoons provide much of the water for farming on the Indian subcontinent, but the pattern of rain shifted dramatically during the last half of the 20th century. In a study appearing online 29 September in Science, researchers pin the blame on soot and other aerosols from human activities. From 1951 to 1999, central-northern India became drier while Pakistan, northwestern India, and southern India got wetter. To determine whether these changes were due to natural variability or human interference (greenhouse gases or aerosols), climate scientists Massimo Bollasina, Yi Ming, and V. Ramaswamy of the Geophysical Fluid Dynamics Laboratory/NOAA in Princeton, New Jersey, compared the history of rainfall with simulations that singled out each climate "forcing" factor to observe its impact. Although greenhouse gases would have increased rainfall over north-central India, the aerosols, they found, caused the "very pronounced drying trend," Ming says. Here's why: Under normal conditions, the northern hemisphere receives more energy from the sun from June to September; that imbalance drives the ocean-atmosphere circulation that powers the monsoons. But atmospheric aerosols shaded the northern hemisphere relative to the southern hemisphere, altering the energy balance between the two-weakening the circulation and altering where the rain falls.

"We present a reference, comprehensive, high-resolution, digital mosaic of ice motion in Antarctica assembled from multiple satellite interferometric synthetic-aperture radar data acquired during the International Polar Year 2007 to 2009. The data reveal widespread, patterned, enhanced flow with tributary glaciers reaching hundreds to thousands of kilometers inland over the entire continent. This view of ice sheet motion emphasizes the importance of basal-slip-dominated tributary flow over deformation-dominated ice sheet flow, redefines our understanding of ice sheet dynamics, and has far-reaching implications for the reconstruction and prediction of ice sheet evolution. "

Right Whales Finally Coming Home Figure "CREDIT: MICHAËL CATANZARITI/WIKIMEDIA COMMONS" After more than 100 years, right whales have returned to their calving grounds in New Zealand, an international team of scientists reports. The 100-ton whales, known for their social frolicking and impressive acrobatic displays, were hunted to extinction in these same waters during the 19th and 20th centuries' era of industrial whaling. A small population managed to survive near remote, sub-Antarctic islands south of New Zealand. In recent years, a few dozen females found their way back to the same bays their ancestors used for bearing their young. Normally, such cultural knowledge is passed from mother to daughter, the researchers say. But the tradition had been lost, until these pioneering females began making the journey once again. Reporting in Marine Ecology Progress Series, the scientists-from Canada, the United States, Australia, and New Zealand-confirmed that some of the females had migrated from the southern islands to New Zealand by comparing the DNA in tissue samples collected from seven whales at both sites. Now that the tradition has been restored, scientists expect more whales to follow the pioneers.

Polar Bears Rooted in Ireland Polar bears and brown bears were separate species by 110,000 years ago. But new genetic studies of fossils and modern bears have revealed some hanky-panky 45,000 years ago, when polar bears interbred with now-extinct Irish brown bears. Hybridization with brown bears is a concern today because declining sea ice cover is forcing polar bears to extend their range and come into contact with brown bears. To understand the implications of hybridization, Beth Shapiro, an evolutionary biologist at Pennsylvania State University, University Park, and her colleagues compared mitochondrial DNA from 8000-year-old polar bear fossils, modern samples of polar bears, and ancient Irish bear fossils. Figure "CREDIT: FOTOSEARCH (2)" Modern polar bear mitochondrial DNA was most similar to that of the extinct Irish brown bear, whereas extinct polar bears had different mitochondria. Thus modern polar bears come from Europe, not islands between Alaska and Siberia, as had been previously thought, the researchers reported in Current Biology. The finding shows that interbreeding occurred during past episodes of climate change didn't destroy a species. "The big question for conservation of polar bears is if hybridization occurs rapidly and in combination with other stressors, will that hybridization have more of a negative effect now than it did in the past," says Andrew Whiteley, a geneticist at the University of Massachusetts, Amherst. http://scim.ag/_polarbears

"A horrendous slaughter is going on out here," said Peter D. Ward, a biologist from the University of Washington, during a recent census of the marine creature in the Philippines. "They're nearly wiped out." The culprit? Growing sales of jewelry and ornaments derived from the lustrous shell. To satisfy the worldwide demand, fishermen have been killing the nautilus by the millions, scientists fear. Now marine biologists have begun to assess the status of its populations and to consider whether it should be listed as an endangered species to curb the shell trade.