With the caloric needs of the planet expected to soar by 50 percent in the next 40 years, planning and investment in global agriculture will become critically important, according a new report. The report, produced by Deutsche Bank, one of the world's leading global investment banks, in collaboration with the University of Wisconsin-Madison's Nelson Institute for Environmental Studies, provides a framework for investing in sustainable agriculture against a backdrop of massive population growth and escalating demands for food, fiber and fuel. "We are at a crossroads in terms of our investments in agriculture and what we will need to do to feed the world population by 2050," says David Zaks, a co-author of the report and a researcher at the Nelson Institute's Center for Sustainability and the Global Environment.

By 2050, world population is expected to exceed 9 billion people, up from 6.5 billion today. Already, according to the report, a gap is emerging between agricultural production and demand, and the disconnect is expected to be amplified by climate change, increasing demand for biofuels, and a growing scarcity of water. "There will come a point in time when we will have difficulties feeding world population," says Zaks, a graduate student whose research focuses on the patterns, trends and processes of global agriculture. Although unchecked population growth will put severe strains on global agriculture, demand can be met by a combination of expanding agriculture to now marginal or unused land, substituting new types of crops, and technology, the report's authors conclude. "The solution is only going to come about by changing the way we use land, changing the things that we grow and changing the way that we grow them," Zaks explains. The report notes that agricultural research and technological development in the United States and Europe have increased notably in the last decade, but those advances have not translated into increased production on a global scale. Subsistence farmers in developing nations, in particular, have benefited little from such developments and investments in those agricultural sectors have been marginal, at best.

The Deutsche Bank report, however, identifies a number of strategies to increase global agricultural productions in sustainable ways, including: · Improvements in irrigation, fertilization and agricultural equipment using technologies ranging from geographic information systems and global analytical maps to the development of precision, high performance equipment. · Applying sophisticated management and technologies on a global scale, essentially extending research and investment into developing regions of the world. · Investing in "farmer competence" to take full advantage of new technologies through education and extension services, including investing private capital in better training farmers. · Intensifying yield using new technologies, including genetically modified crops. · Increasing the amount of land under cultivation without expanding to forested lands through the use of multiple cropping, improving degraded crop and pasturelands, and converting productive pastures to biofuel production. "First we have to improve yield," notes Zaks. "Next, we have to bring in more land in agriculture while considering the environmental implications, and then we have to look at technology."

Bruce Kahn, Deutsche Bank senior investment analyst, echoed Zaks observations: "What is required to meet the challenge of feeding a growing population in a warming world is to boost yield through highly sophisticated land management with precision irrigation and fertilization methods," said Kahn, a graduate of the Nelson Institute. "Farmers, markets and governments will have to look at a host of options including increased irrigation, mechanization, fertilization and the potential benefits of biotech crops." The Deutsche Bank report depended in part on an array of global agricultural analytical tools, maps, models and databases developed by researchers at UW-Madison's Center for Sustainability and the Global Environment. Those tools, including global maps of land supply for crops and pasture, were developed primarily for academic research, says Zaks. The Deutsche Bank report, he continues, is evidence that such tools will have increasing applications in plotting a course for sustainable global agriculture.

The American Dietetic Association has released an updated position paper on vegetarian diets that concludes such diets, if well-planned, are healthful and nutritious for adults, infants, children and adolescents and can help prevent and treat chronic diseases including heart disease, cancer, obesity and diabetes. ADA's position, published in the July issue of the Journal of the American Dietetic Association, represents the Association's official stance on vegetarian diets: "It is the position of the American Dietetic Association that appropriately planned vegetarian diets, including total vegetarian or vegan diets, are healthful, nutritionally adequate and may provide health benefits in the prevention and treatment of certain diseases. Well-planned vegetarian diets are appropriate for individuals during all stages of the life-cycle including pregnancy, lactation, infancy, childhood and adolescence and for athletes."

ADA's position and accompanying paper were written by Winston Craig, PhD, MPH, RD, professor and chair of the department of nutrition and wellness at Andrews University; and Reed Mangels, PhD, RD, nutrition advisor at the Vegetarian Resource Group, Baltimore, Md. The revised position paper incorporates new topics and additional information on key nutrients for vegetarians, vegetarian diets in the life cycle and the use of vegetarian diets in prevention and treatment of chronic diseases. "Vegetarian diets are appropriate for all stages of the life cycle," according to ADA's position. "There are many reasons for the rising interest in vegetarian diets. The number of vegetarians in the United States is expected to increase over the next decade." Vegetarian diets are often associated with health advantages including lower blood cholesterol levels, lower risk of heart disease, lower blood pressure levels and lower risk of hypertension and type 2 diabetes, according to ADA's position. "Vegetarians tend to have a lower body mass index and lower overall cancer rates. Vegetarian diets tend to be lower in saturated fat and cholesterol and have higher levels of dietary fiber, magnesium and potassium, vitamins C and E, folate, carotenoids, flavonoids and other phytochemicals. These nutritional differences may explain some of the health advantages of those following a varied, balanced vegetarian diet."

The position paper draws on results from ADA's evidence analysis process and information from the ADA Evidence Analysis Library to show vegetarian diets can be nutritionally adequate in pregnancy and result in positive maternal and infant health outcomes. Additionally, an evidence-based review showed a vegetarian diet is associated with a lower risk of death from ischemic heart disease. A section in ADA's paper on vegetarian diets and cancer has been significantly expanded to provide details on cancer-protective factors in vegetarian diets. An expanded section on osteoporosis includes roles of fruits, vegetables, soy products, protein, calcium, vitamins D and K and potassium in bone health. "Registered dietitians can provide information about key nutrients, modify vegetarian diets to meet the needs of those with dietary restrictions due to disease or allergies and supply guidelines to meet needs of clients in different areas of the life cycle," the authors said.

With millions of people in the United States eagerly awaiting those July 4 fireworks displays - and our Canadian neighbors doing likewise for their July 1 Canada Day celebrations - here's a prospect for those light shows of the future likely to ignite a smile on Mother Nature's face: A new generation of "green" fireworks is quietly making its way toward the sky.

That's "green" as in environmentally friendly. Fireworks, flares and other so-called "pyrotechnics" traditionally have included potassium perchlorate as the oxidizer, a material that provides the oxygen that fireworks need to burn. Perchlorate, however, is an environmental pollutant with potential adverse effects on people and wildlife. Pyrotechnics contain other ingredients, such color-producing heavy metals, with a similar potential. Studies have shown that perchlorate from community fireworks displays conducted over lakes, for instance, can lead to perchlorate contamination of the water. Full details about how perchlorate contaminates lakes after fireworks displays, Click are contained in a study published in the American Chemical Society's peer-reviewed journal, Environmental Science & Technology. Researchers, however, have developed new pyrotechnic formulas that replace perchlorate with nitrogen-rich materials or nitrocellulose that burn cleaner and produce less smoke, according to an article in ACS's weekly newsmagazine, Chemical & Engineering News (C&EN).

In the article, C&EN Associate Editor Bethany Halford says these nitrogen-rich formulas also use fewer color-producing chemicals, dramatically cutting down on the amount of heavy metals used and lowering their potentially toxic effects. Some of these fireworks have already been used at circuses, rock concerts and other events, but none have been used at large outdoor displays. The problem: cost. The big challenge in launching these "eco-friendly" pyrotechnics into the sky is making them cost-competitive with conventional fireworks while maintaining their dazzle and glow, the article explains. The article notes that fireworks manufacturers have little incentive to further develop the new green fireworks because no federal regulations currently limit releases of perchlorate from pyrotechnics

Modern glaciers, such as those making up the Greenland and Antarctic ice sheets, are capable of undergoing periods of rapid shrinkage or retreat, according to new findings by paleoclimatologists at the University at Buffalo. The paper, published on June 21 in Nature Geoscience, describes fieldwork demonstrating that a prehistoric glacier in the Canadian Arctic rapidly retreated in just a few hundred years. The proof of such rapid retreat of ice sheets provides one of the few explicit confirmations that this phenomenon occurs. Should the same conditions recur today, which the UB scientists say is very possible, they would result in sharply rising global sea levels, which would threaten coastal populations. "A lot of glaciers in Antarctica and Greenland are characteristic of the one we studied in the Canadian Arctic," said Jason Briner, Ph.D., assistant professor of geology in the UB College of Arts and Sciences and lead author on the paper. "Based on our findings, they, too, could retreat in a geologic instant."

The new findings will allow scientists to more accurately predict how global warming will affect ice sheets and the potential for rising sea levels in the future, by developing more robust climate and ice sheet models. Briner said the findings are especially relevant to the Jakobshavn Isbrae, Greenland's largest and fastest moving tidewater glacier, which is retreating under conditions similar to those he studied in the Canadian Arctic. Acting like glacial conveyor belts, tidewater glaciers are the primary mechanism for draining ice sheet interiors by delivering icebergs to the ocean. "These 'iceberg factories' exhibit rapid fluctuations in speed and position, but predicting how quickly they will retreat as a result of global warming is very challenging," said Briner. That uncertainty prompted the UB team to study the rates of retreat of a prehistoric tidewater glacier, of similar size and geometry to contemporary ones, as way to get a longer-term view of how fast these glaciers can literally disappear.

The researchers used a special dating tool at UB to study rock samples they extracted from a large fjord that drained the ice sheet that covered the North American Arctic during the past Ice Age. The samples provided the researchers with climate data over a period from 20,000 years ago to about 5,000 years ago, a period when significant warming occurred. "Even though the ice sheet retreat was ongoing throughout that whole period, the lion's share of the retreat occurred in a geologic instant -- probably within as little as a few hundred years," said Briner. The UB research reveals that the period of rapid retreat was triggered once the glacier entered deep ocean waters, nearly a kilometer deep, Briner said. "The deeper water makes the glacier more buoyant," he explained.

"Because the rates of retreat were so much higher in the deep fjord, versus earlier when it terminated in more shallow waters or on land, the findings suggest that contemporary tidewater glaciers in Greenland and Antarctica that are retreating into deep waters may begin to experience even faster rates of retreat than are currently being observed," said Briner. Right now, Jakobshavn Isbrae is draining into waters that are nearly a kilometer deep, he said, which means that its current rates of retreat -- as fast as 10 kilometers in the past decade -- could continue for the next hundred years. "If modern glaciers do this for several decades, this would rapidly raise global sea level, intercepting coastal populations and requiring vast re-engineering of levees and other mitigation systems," said Briner.

In a paper in Nature Geoscience, a team from the National Oceanography Centre, Southampton (NOCS), along with colleagues from Tübingen (Germany) and Bristol presents a novel continuous reconstruction of sea level fluctuations over the last 520 thousand years. Comparison of this record with data on global climate and carbon dioxide (CO2) levels from Antarctic ice cores suggests that even stabilisation at today's CO2 levels may commit us to sea-level rise over the next couple of millennia, to a level much higher than long-term projections from the Fourth Assessment Report of the Intergovernmental Panel on Climate Change (IPCC).

Little is known about the total amount of possible sea-level rise in equilibrium with a given amount of global warming. This is because the melting of ice sheets is slow, even when temperature rises rapidly. As a consequence, current predictions of sea-level rise for the next century consider only the amount of ice sheet melt that will occur until that time. The total amount of ice sheet melting that will occur over millennia, given the current climate trends, remains poorly understood. The new record reveals a systematic equilibrium relationship between global temperature and CO2 concentrations and sea-level changes over the last five glacial cycles. Projection of this relationship to today's CO2 concentrations results in a sea-level at 25 (±5) metres above the present. This is in close agreement with independent sea-level data from the Middle Pliocene epoch, 3-3.5 million years ago, when atmospheric CO2 concentrations were similar to the present-day value. This suggests that the identified relationship accurately records the fundamental long-term equilibrium behaviour of the climate system over the last 3.5 Million years.

Lead author Professor Eelco Rohling of the University of Southampton's School of Ocean and Earth Science based at NOCS, said: "Let's assume that our observed natural relationship between CO2 and temperature, and sea level, offers a reasonable 'model' for a future with sustained global warming. Then our result gives a statistically sound expectation of a potential total long-term sea-level rise. Even if we would curb all CO2 emissions today, and stabilise at the modern level (387 parts per million by volume), then our natural relationship suggests that sea level would continue to rise to about 25 m above the present. That is, it would rise to a level similar to that measured for the Middle Pliocene." Project partners Professor Michal Kucera (University of Tübingen) and Dr Mark Siddall (University of Bristol), add: "We emphasise that such equilibration of sea level would take several thousands of years. But one still has to worry about the large difference between the inferred high equilibrium sea level and the level where sea level actually stands today. Recent geological history shows that times with similarly strong disequilibria commonly saw pulses of very rapid sea-level adjustment, at rates of 1-2 metres per century or higher."

The new study's projection of long-term sea-level change, based on the natural relationship of the last 0.5 to 3.5 million years, differs considerably from the IPCC's model-based long-term projection of +7 m. The discrepancy cannot be easily explained, and new work is needed to ensure that the 'gap is closed'. The observed relationships from the recent geological past can form a test-bed or reality-check for models, to help them achieve improved future projections.

Some of the substances that are helping to avert the destruction of the ozone layer could increasingly contribute to climate warming, according to scientists from NOAA's Earth System Research Laboratory and their colleagues in a new study published today in the journal Proceedings of the National Academy of Sciences. The authors took a fresh look at how the global use of hydrofluorocarbons (HFCs) is expected to grow in coming decades. Using updated usage estimates and looking farther ahead than past projections (to the year 2050), they found that HFCs-especially from developing countries-will become an increasingly larger factor in future climate warming.

"HFCs are good for protecting the ozone layer, but they are not climate friendly," said David W. Fahey, a scientist at NOAA and second author of the new study. "Our research shows that their effect on climate could become significantly larger than we expected, if we continue along a business-as-usual path." HFCs currently have a climate change contribution that is small (less than 1 percent) in comparison to the contribution of carbon dioxide (CO2) emissions. The authors have shown that by 2050 the HFCs contribution could rise to 7 to 12 percent of what CO2 contributes. And if international efforts succeed in stabilizing CO2 emissions, the relative climate contribution from HFCs would increase further. HFCs, which do not contain ozone-destroying chlorine or bromine atoms, are used as substitutes for ozone-depleting compounds such as chlorofluorocarbons (CFCs) in such uses as refrigeration, air conditioning, and the production of insulating foams. The Montreal Protocol, a 1987 international agreement, has gradually phased out the use of CFCs and other ozone-depleting substances, leading to the development of long-term replacements such as HFCs.

Though the HFCs do not deplete the ozone layer, they are potent greenhouse gases. Molecule for molecule, all HFCs are more potent warming agents than CO2 and some are thousands of times more effective. HFCs are in the "basket of gases" regulated under the 1997 Kyoto Protocol, an international treaty to reduce emissions of greenhouse gases. The new study factored in the expected growth in demand for air conditioning, refrigerants, and other technology in developed and developing countries. The Montreal Protocol's gradual phasing out of the consumption of ozone-depleting substances in developing countries after 2012, along with the complete phase-out in developed countries in 2020, are other factors that will lead to increased usage of HFCs and other alternatives.

Decision-makers in Europe and the United States have begun to consider possible steps to limit the potential climate consequences of HFCs. The PNAS study examined several hypothetical scenarios to mitigate HFC consumption. For example, a global consumption limit followed by a 4 percent annual reduction would cause HFC-induced climate forcing to peak in the year 2040 and then begin to decrease before the year 2050. "While unrestrained growth of HFC use could lead to significant climate implications by 2050, we have shown some examples of global limits that can effectively reduce the HFCs' impact," said John S. Daniel, a NOAA coauthor of the study.

Using 28 years of data from the National Center for Environmental Prediction and the Department of Energy, Ken Caldeira of the Carnegie Institution's Department of Global Ecology and Cristina Archer of California State University, Chico, compiled the first-ever global survey of wind energy available at high altitudes in the atmosphere. The researchers assessed potential for wind power in terms of "wind power density," which takes into account both wind speed and air density at different altitudes. "There is a huge amount of energy available in high altitude winds," said coauthor Ken Caldeira. "These winds blow much more strongly and steadily than near-surface winds, but you need to go get up miles to get a big advantage. Ideally, you would like to be up near the jet streams, around 30,000 feet."

Jet streams are meandering belts of fast winds at altitudes between 20 and 50,000 feet that shift seasonally, but otherwise are persistent features in the atmosphere. Jet stream winds are generally steadier and 10 times faster than winds near the ground, making them a potentially vast and dependable source of energy. Several technological schemes have been proposed to harvest this energy, including tethered, kite-like wind turbines that would be lofted to the altitude of the jet streams. Up to 40 megawatts of electricity could be generated by current designs and transmitted to the ground via the tether. "We found the highest wind power densities over Japan and eastern China, the eastern coast of the United States, southern Australia, and north-eastern Africa," said lead author Archer. "The median values in these areas are greater than 10 kilowatts per square meter. This is unthinkable near the ground, where even the best locations have usually less than one kilowatt per square meter." Included in the analysis were assessments of high altitude wind energy for the world's five largest cities: Tokyo, New York, Sao Paulo, Seoul, and Mexico City. "For cities that are affected by polar jet streams such as Tokyo, Seoul, and New York, the high-altitude resource is phenomenal," said Archer. "New York, which has the highest average high-altitude wind power density of any U.S. city, has an average wind power density of up to 16 kilowatts per square meter." Tokyo and Seoul also have high wind power density because they are both affected by the East Asian jet stream. Mexico City and Sao Paulo are located at tropical latitudes, so they are rarely affected by the polar jet streams and just occasionally by the weaker sub-tropical jets. As a result they have lower wind power densities than the other three cities.

"While there is enough power in these high altitude winds to power all of modern civilization, at any specific location there are still times when the winds do not blow," said Caldeira. Even over the best areas, the wind can be expected to fail about five percent of the time. "This means that you either need back-up power, massive amounts of energy storage, or a continental or even global scale electricity grid to assure power availability. So, while high-altitude wind may ultimately prove to be a major energy source, it requires substantial infrastructure."

Global warming is already occurring in the United States and the choices Americans make today will determine the severity of its impact in the future, according to a new report released today. Researchers representing 13 U.S. government science agencies, major universities and research institutes, including Lawrence Livermore National Laboratory, produced the study entitled "Global Climate Change Impacts in the United States."

Benjamin Santer of LLNL's Program for Climate Model Diagnosis and Intercomparison was a lead author of the first chapter, "Global Climate Change." "This part of the report explains why climate is changing and how we know that we are the ones causing it," Santer said. "Climate change is telling us a consistent story: Humans have had a pronounced effect on global climate." The most comprehensive report to date on the likely national impact of global climate change provides current information on changes in temperatures, rainfall patterns and sea level, and also focuses on the regional and sectoral effects of these changes.

The study finds that Americans are already being influenced by climate change through extreme weather, drought and wildfire, and details how the nation's transportation, agriculture, health, water and energy sectors will be affected in the future. The study also finds that the current trend in the emission of greenhouse gas pollution is significantly above the worst-case scenario examined in this report. Santer's chapter finds: · Human activities have led to large increases in heat-trapping gases over the past century. · Global average temperature and sea level have increased, and precipitation patterns have changed. · The global warming of the past 50 years is due primarily to human-induced increases in heat-trapping gases. Human "fingerprints" also have been identified in many other aspects of the climate system, including changes in ocean heat content, precipitation, atmospheric moisture and Arctic sea ice. · Global temperatures are projected to continue to rise over this century; by how much and for how long depend on a number of factors, including the amount of heat-trapping gas emissions and how sensitive the climate is to those emissions. The emissions responsible for human-induced warming come primarily from the burning of fossil fuels (coal, oil, and gas) with additional contributions from the clearing of forests and agricultural activities.

Global average temperature has risen by about 1.5º Fahrenheit since 1900. By 2100, it is projected to rise another 2º to 10º Fahrenheit. Increases at the lower end of this range are more likely if global heat-trapping gas emissions are cut substantially. If emissions continue to rise at or near current rates, temperature increases are more likely to be near the upper end of the range. A product of the interagency U.S. Global Change Research Program and led by NOAA, the definitive 190-page report is written in plain language, intended to better inform members of the public and policymakers. It was commissioned in 2007. "Our report underscores the importance of reducing heat-trapping emissions by comparing impacts that will result from higher versus lower emissions," said Tom Karl, director of NOAA's National Climatic Data Center in Asheville, N.C. and one of the co-chairs of the report. "It shows that the choices made now will have far-reaching consequences."

The report draws from a large body of scientific information, including the set of 21 Synthesis and Assessment reports from the U.S. Global Change Research Program. The government agencies affiliated with the program include the Departments of Agriculture, Commerce, Defense, Energy, Health and Human Services, Interior, State, and Transportation; the Environmental Protection Agency; NASA; National Science Foundation; Smithsonian Institution; and the United States Agency for International Development.

The report is available for download online: http://www.globalchange.gov/usimpacts

Dairy genetics, nutrition, herd management and improved animal welfare over the past 60 years have resulted in a modern milk production system that has a smaller carbon footprint than mid-20th century farming practices, says a Cornell University study in the Journal of Animal Science (June 2009). "As U.S. and global populations continue to increase, it is critical to adopt management practices and technologies to produce sufficient high-quality food from a finite resource supply, while minimizing effects upon the environment," says Jude Capper, lead author and a recent Cornell post-doctoral researcher working with Dale E. Bauman, Cornell Liberty Hyde Bailey Professor of Animal Science.

The study, "The Environmental Impact of Dairy Production: 1944 compared with 2007," shows that the carbon footprint for a gallon of milk produced in 2007 was only 37 percent of that produced in 1944. Improved efficiency has enabled the U.S. dairy industry to produce 186 billion pounds of milk from 9.2 million cows in 2007, compared to only 117 billion pounds of milk from 25.6 million cows in 1944. This has resulted in a 41 percent decrease in the total carbon footprint for U.S. milk production. Efficiency also resulted in reductions in resource use and waste output. Modern dairy systems only use 10 percent of the land, 23 percent of the feedstuffs and 35 percent of the water required to produce the same amount of milk in 1944. Similarly, 2007 dairy farming produced only 24 percent of the manure and 43 percent of the methane output per gallon of milk compared to farming in 1944.

Trains, planes, buses and automobiles do not only effect the environment via their exhaust pipes. There is a full life-cycle of processes associated with getting from a to b that we rarely acknowledge. Researchers from the Department of Civil and Environmental Engineering at the University of California, Berkeley, have created a framework to help us calculate the true environmental cost of travel. The new framework incorporates less-considered environmental impacts including the damage done by the power plants generating electricity for train travel and upkeep of train stations to the intensive energy costs of airport runway construction and ore extraction undertaken to build a car.

The catalogue of emissions that the researchers have compiled are taken from their own American context but the concept and framework is applicable universally - looking at the full range of vehicles, from hatchbacks and pick-ups to light and heavy railways, small aircrafts and jumbo jets. From cataloguing the varied environmental costs the researchers come to some surprising conclusions. A comparison between light railways in both Boston and San Franciso show that despite Boston boasting a light railway with low operational energy use, their LRT is a far larger greenhouse gas (GHG) emitter because 82 per cent of the energy generated in Boston is fossil-fuel based, compared to only 49 per cent in San Francisco. Total life-cycle energy inputs and GHG emissions contribute an additional 155 per cent for rail, 63 per cent for cars and buses, and 32 per cent for air systems over vehicle exhaust pipe operation.

The researchers also touch on the effect of low passenger occupancy and show that we are naïve to automatically assume one form of transport is more environmentally friendly than another. They conclude from their calculations that a half-full Boston light railway is only as environmentally friendly, per kilometre traveled, as a midsize aircraft at 38 per cent occupancy. Mikhail Chester, researcher at Berkeley, said, "This study creates a framework for comprehensive environmental inventorying of several modes and future assessment of non-conventional fuels and vehicles can follow this methodology in creating technology-specific results. "Through the use of life-cycle environmental assessments, energy and emission reduction decision-making can benefit from the identified interdependencies among processes, services and products."

The most comprehensive modeling yet carried out on the likelihood of how much hotter the Earth's climate will get in this century shows that without rapid and massive action, the problem will be about twice as severe as previously estimated six years ago - and could be even worse than that. The study uses the MIT Integrated Global Systems Model, a detailed computer simulation of global economic activity and climate processes that has been developed and refined by the Joint Program on the Science and Policy of Global Change since the early 1990s. The new research involved 400 runs of the model with each run using slight variations in input parameters, selected so that each run has about an equal probability of being correct based on present observations and knowledge. Other research groups have estimated the probabilities of various outcomes, based on variations in the physical response of the climate system itself. But the MIT model is the only one that interactively includes detailed treatment of possible changes in human activities as well - such as the degree of economic growth, with its associated energy use, in different countries.

Study co-author Ronald Prinn, the co-director of the Joint Program and director of MIT's Center for Global Change Science, says that, regarding global warming, it is important "to base our opinions and policies on the peer-reviewed science," he says. And in the peer-reviewed literature, the MIT model, unlike any other, looks in great detail at the effects of economic activity coupled with the effects of atmospheric, oceanic and biological systems. "In that sense, our work is unique," he says. The new projections, published this month in the American Meteorological Society's Journal of Climate, indicate a median probability of surface warming of 5.2 degrees Celsius by 2100, with a 90% probability range of 3.5 to 7.4 degrees. This can be compared to a median projected increase in the 2003 study of just 2.4 degrees. The difference is caused by several factors rather than any single big change. Among these are improved economic modeling and newer economic data showing less chance of low emissions than had been projected in the earlier scenarios. Other changes include accounting for the past masking of underlying warming by the cooling induced by 20th century volcanoes, and for emissions of soot, which can add to the warming effect. In addition, measurements of deep ocean temperature rises, which enable estimates of how fast heat and carbon dioxide are removed from the atmosphere and transferred to the ocean depths, imply lower transfer rates than previously estimated. Prinn says these and a variety of other changes based on new measurements and new analyses changed the odds on what could be expected in this century in the "no policy" scenarios - that is, where there are no policies in place that specifically induce reductions in greenhouse gas emissions. Overall, the changes "unfortunately largely summed up all in the same direction," he says. "Overall, they stacked up so they caused more projected global warming." While the outcomes in the "no policy" projections now look much worse than before, there is less change from previous work in the projected outcomes if strong policies are put in place now to drastically curb greenhouse gas emissions. Without action, "there is significantly more risk than we previously estimated," Prinn says. "This increases the urgency for significant policy action."

To illustrate the range of probabilities revealed by the 400 simulations, Prinn and the team produced a "roulette wheel" that reflects the latest relative odds of various levels of temperature rise. The wheel provides a very graphic representation of just how serious the potential climate impacts are. "There's no way the world can or should take these risks," Prinn says. And the odds indicated by this modeling may actually understate the problem, because the model does not fully incorporate other positive feedbacks that can occur, for example, if increased temperatures caused a large-scale melting of permafrost in arctic regions and subsequent release of large quantities of methane, a very potent greenhouse gas. Including that feedback "is just going to make it worse," Prinn says.

The lead author of the paper describing the new projections is Andrei Sokolov, research scientist in the Joint Program. Other authors, besides Sokolov and Prinn, include Peter H. Stone, Chris E. Forest, Sergey Paltsev, Adam Schlosser, Stephanie Dutkiewicz, John Reilly, Marcus Sarofim, Chien Wang and Henry D. Jacoby, all of the MIT Joint Program on the Science and Policy of Global Change, as well as Mort Webster of MIT's Engineering Systems Division and D. Kicklighter, B. Felzer and J. Melillo of the Marine Biological Laboratory at Woods Hole. Prinn stresses that the computer models are built to match the known conditions, processes and past history of the relevant human and natural systems, and the researchers are therefore dependent on the accuracy of this current knowledge. Beyond this, "we do the research, and let the results fall where they may," he says. Since there are so many uncertainties, especially with regard to what human beings will choose to do and how large the climate response will be, "we don't pretend we can do it accurately. Instead, we do these 400 runs and look at the spread of the odds." Because vehicles last for years, and buildings and powerplants last for decades, it is essential to start making major changes through adoption of significant national and international policies as soon as possible, Prinn says. "The least-cost option to lower the risk is to start now and steadily transform the global energy system over the coming decades to low or zero greenhouse gas-emitting technologies."

This work was supported in part by grants from the Office of Science of the U.S. Dept. of Energy, and by the industrial and foundation sponsors of the MIT Joint Program on the Science and Policy of Global Change

Should environmental scientists be advocates for environmental policy? To a wildlife ecologist from Michigan Technological University and an environmental ethicist from Michigan State University, the answer is a resounding yes. "Scientists, by virtue of being citizens first and scientists second, have a responsibility to advocate to the best of their abilities and in a justified and transparent manner," say John A. Vucetich and Michael P. Nelson in an advance online publication of a paper in the journal Conservation Biology. The paper is titled "On Advocacy by Environmental Scientists: What, Whether, Why, and How." Vucetich is a wildlife ecologist in Michigan Tech's School of Forest Resources and Environmental Science. Nelson is an environmental ethicist jointly appointed in Lyman Briggs College, the Department of Fisheries and Wildlife, and the Department of Philosophy at Michigan State.

"Much of what has been written about advocacy assesses its appropriateness without adequately assessing its nature," they observe. In a systematic catalog and critique of advocacy arguments-pro and con-Vucetich and Nelson examine the nature of several key arguments, including · Scientific credibility. · The ability to conduct objective scientific research. · The nature of science itself. · The personal and professional costs associated with advocacy. · The belief that science and advocacy are alike. · Social harm that could come from a failure to advocate. · All citizens, including scientists, have a moral obligation to advocate.

"Most of the arguments, whether for or against advocacy, are characterized by some significant deficiency," they say. Take scientific credibility, for example. Those who oppose scientists acting as advocates often say that advocacy undermines a scientist's credibility. Vucetich and Nelson disagree. "As long as a scientist's work is transparently honest, the scientific community is obligated to, and almost always does, confer credibility," they write. "Scientific credibility is not the same as effectiveness. One may have scientific credibility and be effective or ineffective at advocacy." Vucetich and Nelson also analyze and reject most of the usual arguments favoring scientists acting as policy advocates "Only one argument seems robustly sound and valid," Vucetich and Nelson say. That is, as citizens first and scientists second, scientists have a responsibility to use their scientific data and insights to guide policy decisions. The ethicist and the scientist call it an ideal marriage of philosophical ethics and scientific commitment to data collection and analysis.

"Our assessment calls for more active participation by scientists in matters of policy," they conclude. "Broad participation will undoubtedly result in disagreement among good scientists and will substantially complicate the policy-making process. However, our goal here should not be simplicity, but rather the betterment of society." Mark Hixon, a leading coral reef ecologist at Oregon State University, endorses the pair's conclusion. "Nelson and Vucetich's excellent paper is the first rigorous analysis of the logic underlying arguments for and against scientists participating in environmental policy debates," he said. "The extent to which a scientist engages in advocacy is a personal decision that should be respected by peers, given that there are real benefits and costs, as well as responsibilities, involved. I personally decided that I did not abdicate my citizenship when I became scientist, so I attempt to live a personal precautionary principle: The risk of not participating in policy debates--severe environmental degradation--is far greater than the risk of participating."

A new study from Harvard School of Public Health (HSPH) researchers found that participants who drank for a week from polycarbonate bottles, the popular, hard-plastic drinking bottles and baby bottles, showed a two-thirds increase in their urine of the chemical bisphenol A (BPA). Exposure to BPA, used in the manufacture of polycarbonate and other plastics, has been shown to interfere with reproductive development in animals and has been linked with cardiovascular disease and diabetes in humans. The study is the first to show that drinking from polycarbonate bottles increased the level of urinary BPA, and thus suggests that drinking containers made with BPA release the chemical into the liquid that people drink in sufficient amounts to increase the level of BPA excreted in human urine.

The study appears on the website of the journal Environmental Health Perspectives and is freely available at http://www.ehponline.org/members/2009/0900604/0900604.pdf. In addition to polycarbonate bottles, which are refillable and a popular container among students, campers and others and are also used as baby bottles, BPA is also found in dentistry composites and sealants and in the lining of aluminum food and beverage cans. (In bottles, polycarbonate can be identified by the recycling number 7.) Numerous studies have shown that it acts as an endocrine-disruptor in animals, including early onset of sexual maturation, altered development and tissue organization of the mammary gland and decreased sperm production in offspring. It may be most harmful in the stages of early development. "We found that drinking cold liquids from polycarbonate bottles for just one week increased urinary BPA levels by more than two-thirds. If you heat those bottles, as is the case with baby bottles, we would expect the levels to be considerably higher. This would be of concern since infants may be particularly susceptible to BPA's endocrine-disrupting potential," said Karin B. Michels, associate professor of epidemiology at HSPH and Harvard Medical School and senior author of the study.

The researchers, led by first author Jenny Carwile, a doctoral student in the department of epidemiology at HSPH, and Michels, recruited Harvard College students for the study in April 2008. The 77 participants began the study with a seven-day "washout" phase in which they drank all cold beverages from stainless steel bottles in order to minimize BPA exposure. Participants provided urine samples during the washout period. They were then given two polycarbonate bottles and asked to drink all cold beverages from the bottles during the next week; urine samples were also provided during that time. The results showed that the participants' urinary BPA concentrations increased 69% after drinking from the polycarbonate bottles. (The study authors noted that BPA concentrations in the college population were similar to those reported for the U.S. general population.) Previous studies had found that BPA could leach from polycarbonate bottles into their contents; this study is the first to show a corresponding increase in urinary BPA concentrations in humans.

One of the study's strengths, the authors note, is that the students drank from the bottles in a normal use setting. Additionally, the students did not wash their bottles in dishwashers nor put hot liquids in them; heating has been shown to increase the leaching of BPA from polycarbonate, so BPA levels might have been higher had students drunk hot liquids from the bottles. Canada banned the use of BPA in polycarbonate baby bottles in 2008 and some polycarbonate bottle manufacturers have voluntarily eliminated BPA from their products. With increasing evidence of the potential harmful effects of BPA in humans, the authors believe further research is needed on the effect of BPA on infants and on reproductive disorders and on breast cancer in adults. "This study is coming at an important time because many states are deciding whether to ban the use of BPA in baby bottles and sippy cups. While previous studies have demonstrated that BPA is linked to adverse health effects, this study fills in a missing piece of the puzzle-whether or not polycarbonate plastic bottles are an important contributor to the amount of BPA in the body," said Carwile.

Experts say that more than half of the world's coral reefs could disappear in the next 50 years, in large part because of higher ocean temperatures caused by climate change. But now Stanford University scientists have found evidence that some coral reefs are adapting and may actually survive global warming. "Corals are certainly threatened by environmental change, but this research has really sparked the notion that corals may be tougher than we thought," said Stephen Palumbi, a professor of biology and a senior fellow at Stanford's Woods Institute for the Environment.

Palumbi and his Stanford colleagues began studying the resiliency of coral reefs in the Pacific Ocean in 2006 with the support of a Woods Institute Environmental Venture Project grant. The project has expanded and is now being funded by Conservation International and the Bio-X program at Stanford. "The most exciting thing was discovering live, healthy corals on reefs already as hot as the ocean is likely to get 100 years from now," said Palumbi, director of Stanford's Hopkins Marine Station. "How do they do that?" Corals in peril Coral reefs form the basis for thriving, healthy ecosystems throughout the tropics. They provide homes and nourishment for thousands of species, including massive schools of fish, which in turn feed millions of people across the globe. Corals rely on partnerships with tiny, single-celled algae called zooxanthellae. The corals provide the algae a home, and, in turn, the algae provide nourishment, forming a symbiotic relationship. But when rising temperatures stress the algae, they stop producing food, and the corals spit them out. Without their algae symbionts, the reefs die and turn stark white, an event referred to as "coral bleaching." During particularly warm years, bleaching has accounted for the deaths of large numbers of corals. In the Caribbean in 2005, a heat surge caused more than 50 percent of corals to bleach, and many still have not recovered, according to the Global Coral Reef Monitoring Network, an international collaboration of government officials, policymakers and marine scientists, including Palumbi. Havens of healthy reefs

In recent years, scientists discovered that some corals resist bleaching by hosting types of algae that can handle the heat, while others swap out the heat-stressed algae for tougher, heat-resistant strains. Palumbi's team set out to investigate how widely dispersed these heat-tolerant coral reefs are across the globe and to learn more about the biological processes that allow them to adapt to higher temperatures. In 2006, Palumbi and graduate student Tom Oliver, now a postdoctoral researcher at Stanford, traveled to Ofu Island in American Samoa. Ofu, a tropical coral reef marine reserve, has remained healthy despite gradually warming waters. The island offered the perfect laboratory setting, Oliver said, with numerous corals hosting the most common heat-sensitive and heat-resistant algae symbionts. Ofu also has pools of varying temperatures that allowed the research team to test under what conditions the symbionts formed associations with corals.

In cooler lagoons, Oliver found only a handful of corals that host heat-resistant algae exclusively. But in hotter pools, he observed a direct increase in the proportion of heat-resistant symbionts, suggesting that some corals had swapped out the heat-sensitive algae for more robust types. These results, combined with regional data from other sites in the tropical Pacific, were published in the journal Marine Ecology Progress Series in March 2009. Global pattern To see if this pattern exists on a global scale, the researchers turned to Kevin Arrigo, an associate professor of environmental Earth system science at Stanford and an expert on remote satellite sensing of marine microalgae. Arrigo gathered worldwide oceanographic data on a variety of environmental variables, including ocean acidity, the frequency of weather events and sea-surface temperature. Oliver then compiled dozens of coral reef studies from across the tropics and compared them to Arrigo's environmental data. The results revealed the same pattern: In regions where annual maximum ocean temperatures were above 84 to 88 degrees Fahrenheit (29 to 31 degrees Celsius), corals were avoiding bleaching by hosting higher proportions of the heat-resistant symbionts. Most corals bleach when temperatures rise 1.8 F (1 C) above the long-term normal highs. But heat-tolerant symbionts might allow a reef to handle temperatures up to 2.6 F (1.5 C) beyond the bleaching threshold. That might be enough to help get them through the end of the century, Oliver said, depending on the severity of global warming. A 2007 report by the United Nations International Panel on Climate Change concluded that the average surface temperature of the Earth is likely to increase 3.6 to 8.1 F (2 to 4.5 C) by 2100. In this scenario, the symbiont switch alone may not be enough to help corals survive through the end of the century. But with the help of other adaptive mechanisms, including natural selection for heat-tolerant corals, there is still hope, Oliver said.

"These findings show that, given enough time, many corals can match hotter environments by hosting heat-resistant symbionts," he explained. "While hopeful, the work also suggests that modern environments are changing so rapidly that corals may not be able to keep up. It comes down to a calculation of the rates of environmental change versus the rates of adaptation." Heat-resistant corals also turn out to be more tolerant of increases in ocean acidity, which occurs when the ocean absorbs excess carbon dioxide from the atmosphere-another potential threat to coral reefs. This finding suggests that corals worldwide are adapting to increases in acidity as well as heat, Oliver said, and that across the tropics, corals with the ability to switch symbionts will do so to survive. Future protection

The problem of coral bleaching comes down to a collapse of the algae at the cellular level, Oliver explained. But the molecular biology of corals and their zooxanthellae under stress is shockingly understudied, he added. To examine the corals and their symbionts at the molecular level, the researchers are collaborating with John Pringle, a professor of genetics at Stanford. Pringle and his lab have set up tanks where anemones, corals and their algae are exposed to a variety of treatments, including changes in temperature, acidity and light. That research is ongoing. "What I hope is that we will learn some really deep and interesting things about the cellular and genetic mechanisms that allow this symbiosis to function, and about the mechanisms that come into play when the symbiosis is breaking down under stress," Pringle said. "The longer-range hope is that having that understanding will contribute to efforts in coral conservation."

The ultimate goal is to find protein biomarkers that indicate signs of heat stress and potential heat resistance, Oliver explained. Then coral reef managers could go to a reef, take small coral samples and test for the presence of the biomarkers to see how resilient the reef will be to higher temperatures. "With this tool, managers could identify existing populations that may be more resistant to climate change and potentially prioritize their protection from everything else that kills coral reefs, like fishing and [agricultural] runoff," Oliver said. "Although we are doing things to the planet we have never done before, it's hard to imagine that these corals, which have existed for a quarter of a billion years, only have 50 years left," Palumbi said. "And part of our job might be to figure out where the tougher ones live and protect those places."

Last year's energy crisis highlighted an unforseen by-product of the looming fuel shortages of the 21st century. Petroleum-based products such as plastics that society takes for granted but now requires to function will run out with the oil. Scientists are looking to microorganisms to pick up the slack and help produce environmentally friendly plastics, according to research presented today at the 109th General Meeting of the American Society for Microbiology. "Organic waste from agriculture, industries and households forms a very large resource that is currently discarded or at best transformed into biogas. From a sustainability point of view it is desired to convert these organic resources in chemicals," says Mark van Loosdrecht of Delft University of Technology in the Netherlands, who has been working on using bacteria to transform this waste into bioplastics known as polyhydroxyalkanoates (PHAs).

PHAs are linear polyesters produced by bacterial fermentation of sugar or lipids (fats). They are produced by the bacteria to store carbon and energy. More than 150 different monomers can be combined within this family to give materials with extremely different properties. These plastics are biodegradeable and are used in the production of bioplastics. However, the high cost of PHA production compared to conventional plastics has limited their use in a wide range of applications. Using technology derived from wastewater treatment systems, van Loosdrecht and his lab have developed a process using open microbial cultures to convert organic wastes to PHAs. This new process is able to produce just as much PHA as existing processes at specific rates that are up to three times faster. Kevin O'Connor at the University College in Dublin, Ireland, has also developed a new process using bacteria to produce PHAs from waste, only the waste is not organic. O'Connor has found a way to transform traditional plastics into biodegradable plastics. Using a process called pyrolysis, the waste plastics are heated in the absence of air, causing a breakdown of the molecular bonds. What's left is an oil that is then fed to natural soil bacteria that use it to produce PHA.

The process was initially developed using polystyrene, one of the most widely used plastics, but O'Connor says it also works on other plastics including polyethylene terephthalate (PET), the plastic used to make water bottles. Richard Gross from the Polytechnic University in Brooklyn, New York, is using bacteria that produce a building block from vegetable oils that can be used to make a plastic that is very much like polyethylene. However, unlike polyethylene, when it becomes waste it can be converted by mild enzymatic methods to biodiesel fuel. "We were challenged by the Defense Advanced Research Projects Agency (DARPA) come up with a plastic that could be broken back down to liquid fuel. I thought about that and realized that we needed to make plastic from building blocks that could later serve as fuel elements," says Gross. That basic starting material for this work are vegetable oils that consist of fatty acids. Gross in collaboration with colleagues at DNA 2.0 (Menlo Park, CA) engineered a yeast to specifically ferment a fatty acid into a compound that can be processed into a bioplastic. "The plastic is very much like polyethylene. It will process like it, it will feel like it, people will be comfortable with it," says Gross.

When the plastic becomes waste, it can be broken down and processed into biodiesel using an enzyme. While the process for conversion of the plastic to biodiesel works in the lab, it is not efficient enough for commercial viability. "We are now looking for a really efficient enzyme that can convert the plastic back to its building blocks. We have found microbes and enzymes that do break it down completely but we still need to improve their efficiencies," says Gross.

Some researchers hope to turn plants into a renewable, nonpolluting replacement for crude oil. To achieve this, scientists have to learn how to convert plant biomass into a building block for plastics and fuels cheaply and efficiently. In new research, chemists have successfully converted cellulose -- the most common plant carbohydrate -- directly into the building block called HMF in one step. The result builds upon earlier work by researchers at the Department of Energy's Pacific Northwest National Laboratory. In that work, scientists produced HMF from simple sugars derived from cellulose. In this new work, researchers developed a way to bypass the sugar-forming step and go straight from cellulose to HMF. This simple process generates a high yield of HMF and allows the use of raw cellulose as feed material, the researchers report in an upcoming issue of Applied Catalysis A. "In biomass like wood, corn stover and switchgrass, cellulose is the most abundant polymer that researchers are trying to convert to biofuels and plastics," said chemist Z. Conrad Zhang, who led the work while at PNNL's Institute for Interfacial Catalysis.

HMF, also known as 5-hydroxymethylfurfural, can be used as a building block for plastics and "biofuels" such as gasoline and diesel, essentially the same fuels processed from crude oil. In previous work, PNNL researchers used a chemical and a solvent known as an ionic liquid to convert the simple sugars into HMF. The chemical, a metal chloride known as chromium chloride, converted sugar into highly pure HMF. But to be able to feed cellulosic biomass directly from nature, the team still needed to break down cellulose into simple sugars -- Zhang and colleagues wanted to learn how to skip that step. The ionic liquid has the added benefit of being able to dissolve cellulose, which as anyone who's boiled leafy vegetables knows can be stringy and hard to dissolve. Compounds called catalysts speed up the conversion of cellulose to HMF. After trying different metal chloride catalysts in the ionic solvent, they found a pair of catalysts that worked well: A combination of copper chloride and chromium chloride under 120 degrees Celsius broke down the cellulose without creating a lot of unwanted byproducts. In additional experiments, the team tested how well their method compared to acid, a common way to break down cellulose. The metal chlorides-ionic liquid system worked ten times faster than the acid and at much lower temperatures. In addition, the paired metal chloride catalysts allowed Zhang's research team to avoid using another compound under investigation, a mineral acid, that is known to degrade HMF. Optimizing their method, the team found that they could consistently achieve a high yield of HMF -- the method converted about 57 percent of the sugar content in the cellulose feedstock to HMF through this single step process.

The team recovered more than 90% of the HMF formed, and the final product from the process was 96% pure. In addition, the metal chlorides and ionic liquid could be reused multiple times without losing their effectiveness. Being able to recycle the materials will lower the cost of HMF production. "This paper is a tremendous breakthrough. By combining the cellulose-breakdown and sugar-conversion steps, we are very close to a single-step method of converting raw biomass into a new platform chemical -- a chemical you can readily turn into a transportation fuel or for synthesis of plastics and other useful materials," said PNNL geochemist and study coauthor Jim Amonette. "Advances like this can help reduce our dependence on fossil fuels."

The answer to the looming fuel crisis in the 21st century may be found by thinking small, microscopic in fact. Microscopic organisms from bacteria and cyanobacteria, to fungi and microalgae, are biological factories that are proving to be efficient sources of inexpensive, environmentally friendly biofuels that can serve as alternatives to oil, according to research presented at the 109th General Meeting of the American Society for Microbiology. "We have been charged to develop the next generation of cellulosic biofuels. When we successfully supply sources of energy to the grid from non-food, cellulosic, parts of plants we will mitigate the food versus fuel debate," says Tim Donohue of the University of Wisconsin, Madison, one of two directors of Department of Energy Bioenergy Research Centers who spoke today in a session at the meeting. When it comes to alternative fuels, currently ethanol is king. Almost all ethanol produced in the United States is fermented from readily available sugars in corn starch or corn kernels. Producing ethanol from corn has also come under much criticism lately, accused of being responsible for rising food prices.

Researchers are looking at alternate biomasses as food for microorganisms to ferment into ethanol. The most attractive are known as lignocellulosic biomass and include wood residues (including sawmill and paper mill discards), municipal paper waste, agricultural residues (including sugarcane bagasse), dedicated energy crops (like switchgrass) or the non-edible parts of corn like cobs, stalks or stover. The problem is, unlike corn starch, the sugars necessary for fermentation are trapped inside the lignocellulose part of this plant biomass. The key to ending the food versus fuel debate is unlocking the sugars trapped in cellulosic biomass. To do that, some scientists have taken a page out of the playbook of the pharmaceutical industry. Pharmaceutical companies routinely use a process known as high throughput screening to rapidly test thousands of compounds for potential new drugs. Martin Keller at Oak Ridge National Laboratory, the DOE bioenergy research center director, and his lab have adapted the method to rapidly test poplar tree samples for their ability to give up sugars. "We for the first time ever have developed a super-screening pipeline to handle thousands of samples. We took samples from approximately 1,300 poplar trees in the northwestern United States and used the screening pipeline to see if there was a difference in sugar release," says Keller. "Trees can be very different. Some trees can be easier to digest, even within the same species."

Keller is not sure why some poplars are more likely to give up their sugars than others. It could be genetic or the result of some environmental factor or a bit of both. They are now conducting experiments, growing poplar saplings under controlled environments to better understand. In addition to studying the biomass itself, Keller's lab is also looking for microbes or microbial products that can help break it down into simple sugars. They are currently studying a bacterium found in a hot spring in Yellowstone known as Anaerocellum. It grows at approximately 80 degrees Celsius and is what is known as a consolidate bioprocessing microbe: It can not only break down the cellulosic biomass to sugars but ferment it to acetate and ethanol, saving time and money. "Right now it is expensive to break down cellulosic biomass. That is why we don't have a sustainable biofuels industry. This is what we as a center are working to overcome," says Keller. Once they have overcome that problem, there are companies ready to move forward. Andreas Schirmer from the company LS9 in South San Francisco describes a unique strategy. LS9 has engineered a proprietary microbe to produce UltraClean™ diesel in a one-step process. They have discovered a way to exploit the pathway that microbes use to make energy-rich fatty acids for the synthesis of cell membranes and energy storage compounds, and divert them for their own purposes. Inside the fermentor, the microbes and feedstock sit in water, so the oil-like fuel compounds rise to the surface and can be easily collected, much more efficiently than the energy rich distillation process necessary to produce ethanol.

Schirmer says they are currently using sugar cane as a cost-effective option and estimates an 80 percent reduction in carbon footprint compared to petroleum-based fuels. "It is a bridge feedstock. Once second generation feedstocks come online we will be able to convert production over to them quickly and achieve even greater reductions in greenhouse gas emissions," says Schirmer. Beside ethanol and biodiesel, researchers are also looking at producing hydrogen from renewable resources. Donohue's lab is working with purple bacteria called Rhodobacter sphaeroides that use photosynthesis to produce hydrogen from a combination of cellulosic feedstocks and sunlight. The hydrogen can then converted to electricity using fuel cells that his lab is also developing. They have completed laboratory scale prototype "microbial batteries" using the bacteria and the fuel cells in a single enclosed system that, when exposed to sunlight, produces enough electrical current to power a laptop. "This is just a look under the hood at the types of activities that are going on in the United States to take advantage of microbial activities and deploy them to create the next generation of fuels," says Donohue.

The potential contribution to sea level rise from a collapse of the West Antarctic Ice Sheet (WAIS) have been greatly overestimated, according to a new study published in the journal Science. Scientists estimate global sea level would rise 3.3 metres, not five or six, as previously thought. The Atlantic and Pacific seaboards of the US, even in the case of a partial collapse, would experience the largest increases, threatening cities such as New York, Washington DC and San Francisco. Long thought of as the sleeping giant with respect to sea level rise, Antarctica holds about nine times the volume of ice of Greenland. Its western ice sheet is of particular interest to scientists due to its unusual below-sea level topography, which is believed to make it inherently unstable. But the area's potential contribution to sea level has been greatly overestimated, according to new calculations.

Professor Jonathan Bamber at Bristol University, lead author of the study, said: "There's a vast body of research that's looked at the likelihood of a WAIS collapse and what implications such a catastrophic event would have for the globe. Yet all of these studies have assumed a five- to-six-metre contribution to sea level rise. Our calculation shows those estimates are much too large, even on a thousand year timescale." Instead of assuming a complete disintegration of the whole WAIS, Bamber and colleagues used models, based on glaciological theory, to simulate how the massive ice sheet would respond if the floating ice shelves fringing the continent broke free. Vast ice shelves currently block the WAIS from spilling into the Weddell and Ross Seas, limiting total ice loss to the ocean. According to theory, if these floating ice shelves were removed, sizeable areas of the WAIS would become, in effect, undammed, triggering an acceleration of the ice sheet towards the ocean and a "rapid" inland migration of the grounding line, the point where the ice sheet's margins meets the ocean and begins to float. The most unstable areas of the WAIS are those grounded below sea level on bedrock with negative bedslope, where the bedrock slopes downwards inland. Once undammed, these areas would quickly become buoyant, forming new floating ice shelves further inland and, in time, precipitating further break up and collapse. For their calculations, the researchers assumed that only these areas would collapse and contribute to sea level rise. In contrast, they assumed areas grounded above sea level, or on bedrock that slopes upwards inland, would likely retain substantial ice masses.

Professor Bamber said: "Unlike the world's other major ice sheets - the East Antarctic Ice Sheet and Greenland - WAIS is the only one with such an unstable configuration." Just how "rapid" a collapse of the WAIS would be is largely unknown. Though if such a large mass of ice steadily melted over 500 years, as suggested in an early study, it would add about 6.5 millimetres per year to sea level rise: twice the current rate due to all sources. Professor Bamber added: "Interestingly, the pattern of sea level rise is independent of how fast or how much of the WAIS collapses. Even if the WAIS contributed only a metre of sea level rise over many years, sea levels along North America's shorelines would still increase 25 per cent more than the global average." Regional variations in sea level would be largely driven by the redistribution of ice mass from the Antarctic continent to the oceans, according to the study. With less mass at the South Pole, Earth's gravity field would weaken in the Southern Hemisphere and strengthen in the North, causing water to pile up in the northern oceans. This redistribution of mass would also affect Earth's rotation, which in turn would cause water to build up along the North American continent and in the Indian Ocean.

The familiar model of Atlantic ocean currents that shows a discrete "conveyor belt" of deep, cold water flowing southward from the Labrador Sea is probably all wet. New research led by Duke University and the Woods Hole Oceanographic Institution relied on an armada of sophisticated floats to show that much of this water, originating in the sea between Newfoundland and Greenland, is diverted generally eastward by the time it flows as far south as Massachusetts. From there it disburses to the depths in complex ways that are difficult to follow. A 50-year-old model of ocean currents had shown this southbound subsurface flow of cold water forming a continuous loop with the familiar northbound flow of warm water on the surface, called the Gulf Stream. "Everybody always thought this deep flow operated like a conveyor belt, but what we are saying is that concept doesn't hold anymore," said Duke oceanographer Susan Lozier. "So it's going to be more difficult to measure these climate change signals in the deep ocean." And since cold Labrador seawater is thought to influence and perhaps moderate human-caused climate change, this finding may affect the work of global warming forecasters.

"To learn more about how the cold deep waters spread, we will need to make more measurements in the deep ocean interior, not just close to the coast where we previously thought the cold water was confined," said Woods Hole's Amy Bower. Lozier, a professor of physical oceanography at Duke's Nicholas School of the Environment and Bower, a senior scientist in the department of physical oceanography at the Woods Hole Institution, are co-principal authors of a report on the findings published in the May 14 issue of the research journal Nature.

Their research was supported by the National Science Foundation. Climatologists pay attention to the Labrador Sea because it is one of the starting points of a global circulation pattern that transports cold northern water south to make the tropics a little cooler and then returns warm water at the surface, via the Gulf Stream, to moderate temperatures of northern Europe. Since forecasters say effects of global warming are magnified at higher latitudes, that makes the Labrador Sea an added focus of attention. Surface waters there absorb heat-trapping carbon dioxide from the atmosphere. And a substantial amount of that CO2 then gets pulled underwater where it is no longer available to warm Earth's climate. "We know that a good fraction of the human caused carbon dioxide released since the Industrial revolution is now in the deep North Atlantic" Lozier said. And going along for the ride are also climate-caused water temperature variations originating in the same Labrador Sea location. The question is how do these climate change signals get spread further south? Oceanographers long thought all this Labrador seawater moved south along what is called the Deep Western Boundary Current (DWBC), which hugs the eastern North American continental shelf all the way to near Florida and then continues further south.

But studies in the 1990s using submersible floats that followed underwater currents "showed little evidence of southbound export of Labrador sea water within the Deep Western Boundary Current (DWBC)," said the new Nature report. Scientists challenged those earlier studies, however, in part because the floats had to return to the surface to report their positions and observations to satellite receivers. That meant the floats' data could have been "biased by upper ocean currents when they periodically ascended," the report added. To address those criticisms, Lozier and Bower launched 76 special Range and Fixing of Sound floats into the current south of the Labrador Sea between 2003 and 2006. Those "RAFOS" floats could stay submerged at 700 or 1,500 meters depth and still communicate their data for a range of about 1,000 kilometers using a network of special low frequency and amplitude seismic signals. But only 8 percent of the RAFOS floats' followed the conveyor belt of the Deep Western Boundary Current, according to the Nature report. About 75 percent of them "escaped" that coast-hugging deep underwater pathway and instead drifted into the open ocean by the time they rounded the southern tail of the Grand Banks. Eight percent "is a remarkably low number in light of the expectation that the DWBC is the dominant pathway for Labrador Sea Water," the researchers wrote. Studies led by Lozier and other researchers had previously suggested cold northern waters might follow such "interior pathways" rather than the conveyor belt in route to subtropical regions of the North Atlantic. But "these float tracks offer the first evidence of the dominance of this pathway compared to the DWBC."

Since the RAFOS float paths could only be tracked for two years, Lozier, her graduate student Stefan Gary, and German oceanographer Claus Boning also used a modeling program to simulate the launch and dispersal of more than 7,000 virtual "efloats" from the same starting point. "That way we could send out many more floats than we can in real life, for a longer period of time," Lozier said. Subjecting those efloats to the same underwater dynamics as the real ones, the researchers then traced where they moved. "The spread of the model and the RAFOS float trajectories after two years is very similar," they reported. "The new float observations and simulated float trajectories provide evidence that the southward interior pathway is more important for the transport of Labrador Sea Water through the subtropics than the DWBC, contrary to previous thinking," their report concluded. "That means it is going to be more difficult to measure climate signals in the deep ocean," Lozier said. "We thought we could just measure them in the Deep Western Boundary Current, but we really can't."

Reusable and recyclable packaging are shooting up the news, public, and political agenda, and increasingly can offer a cutting edge to the growing number of environmentally-conscious consumers. But what makes a refillable product successful, and why do so many fail to hit the mark? A new study publishing today in Packaging Technology & Science examines what consumers want from refillable packaging and how manufacturers can make a success of their green initiatives. The study's key finding was that pricing is essential; consumers believe that refills must be cheaper than fully packaged options, but that quality must not be sacrificed for cheapness. Most consumers surveyed said that their reasons for using, or wanting to use, refillable packaging was because of environmental issues. Perhaps surprisingly, this was also the main driver for businesses, who felt that it could show them as responsible whilst also attaining some cost-savings.

To get a complete overview of the issues surrounding refillable packaging, the researchers completed a thorough review of all literature in this area, surveyed consumers, and held workshops with business stakeholders in the UK. Of the consumers surveyed (89 returned questionnaires) the researchers found some interesting figures, including: · Only 26% had used self-dispense style refills (such as refilling toiletries) · 55% had positive experiences where the original packaging was swapped for a new product (such as milk bottles and ink cartridges) · Less than a quarter had used a deposit system where empty packaging is returned for a financial incentive, compared to Finland where 98% of all soft drink and beer packaging is refillable, 90% in Denmark and 80% in the Netherlands

"There are a wide range of business and sustainability advantages to engaging with refills. If refillable packaging is designed carefully and applied to appropriate products it has a great opportunity to reduce household waste, and also reduce the amount of natural resources needed to package and deliver goods to the consumer," said lead researcher Dr. Vicky Lofthouse of the Department of Design & Technology at Loughborough University. "I believe that the findings from this study have dramatically increased levels of understanding about the potential of refillable packaging and how it might be successfully utilised by business." For consumers, the main requirements for convenient and useable refillable packaging were: something quick and easy to use; lighter and easily transported; creates less waste and is less bulky; delivered in a convenient way; and is specifically suited to the purpose and nature of the product. For businesses, refills can generate high levels of customer loyalty, as they can tie the customer to the system if designed correctly. The researchers also found that as long as there is a clear reason as to why a refill approach is better and the refill is delivered well, people do not mind whether or not they are given a choice to participate.

"One of the key factors with refillable packaging is that if it doesn't work, or consumers don't buy in to it, it can lead to more waste or more cost to the business. For example, if consumers treat it like a non-refill product and throw all of the packaging away each time, it could lead to more waste than a traditional product as the benefits envisioned by the designer are not being fulfilled," warned Lofthouse. "There are other issues such as extra shelf space and storage issues, which businesses have to consider, so it is important that the benefits are worth it."

With the U.S. Congress beginning to consider regulations on greenhouse gases, a troubling hypothesis about how the sun may impact global warming is finally laid to rest. Carnegie Mellon University's Peter Adams along with Jeff Pierce from Dalhousie University in Halifax, Canada, have developed a model to test a controversial hypothesis that says changes in the sun are causing global warming. The hypothesis they tested was that increased solar activity reduces cloudiness by changing cosmic rays. So, when clouds decrease, more sunlight is let in, causing the earth to warm. Some climate change skeptics have tried to use this hypothesis to suggest that greenhouse gases may not be the global warming culprits that most scientists agree they are.

In research published in Geophysical Research Letters, and highlighted in the May 1 edition of Science Magazine, Adams and Pierce report the first atmospheric simulations of changes in atmospheric ions and particle formation resulting from variations in the sun and cosmic rays. They find that changes in the concentration of particles that affect clouds are 100 times too small to affect the climate. "Until now, proponents of this hypothesis could assert that the sun may be causing global warming because no one had a computer model to really test the claims," said Adams, a professor of civil and environmental engineering at Carnegie Mellon. "The basic problem with the hypothesis is that solar variations probably change new particle formation rates by less than 30 percent in the atmosphere. Also, these particles are extremely small and need to grow before they can affect clouds. Most do not survive to do so," Adams said.

Despite remaining questions, Adams and Pierce feel confident that this hypothesis should be laid to rest. "No computer simulation of something as complex as the atmosphere will ever be perfect," Adams said. "Proponents of the cosmic ray hypothesis will probably try to question these results, but the effect is so weak in our model that it is hard for us to see this basic result changing."

Nano-research on drill cores from the North Sea might help increase extraction rates of oil in Denmark It is a mystery to many people why the world is running out of oil when most of the world's oilfields have only been half emptied. However some of the oil that has been located is trapped as droplets of oil in small cavities in the surrounding rock or is stuck to the walls of the underground cavity and cannot be accessed by the techniques currently used in the oil industry. Now, new research may have come up with an explanation as to where and how North Sea oil clings to underground rocks. This explanation could turn out to be the first step on the way to developing improved oil production techniques with the intent of increasing oil production from Danish oil fields.

A research group at the Nano-Science Center, part of the Institute of Chemistry at University of Copenhagen has investigated drill cores collected from North Sea oil fields using an atomic force microscope. Their investigations show that the spaces which contain oil have totally different surface qualities than expected from our knowledge of the minerals which make up the rock. The rocks which contain oil in the Danish part of the North Sea are primarily chalk - the same type of rock that the cliffs of Stevns and Møns are made of. Assistant Professor Tue Hassenkam lead the research, whose preliminary results were published in the respected scientific publication PNAS (Proceedings of the National Academy of Sciences) this week. He says that this is the first time that investigations of this type have been carried out on chalk from an oil field in the North Sea. 'Previous investigations were carried out on the surface properties of pure mineral crystals. But our investigation has shown that this chalk has a different and more complex structure' says Tue Hassenkam.

The oil bearing layers in the subsurface are reminiscent of a sponge. The oil "hides" in tiny pores and gaps and only some of the oil can be pressed out of the chalk and into the borehole by injecting water into the chalk layer. The rest is left behind as small droplets of oil surrounded by water either in small gaps in the rock or stuck to the walls of the pores. The chalk particles ought to repel oil if they act like particles of the mineral calcite, which chalk is almost 100% made up of. However the new investigations, carried out with a particularly powerful microscope, have shown that the surfaces of the pores in the chalk are partially covered in a material which oil can stick to. Ass. Prof. Hassenkam believes that the surprising behaviour of the material in the surface of the chalk can be explained by studying how the chalk was formed. 'Chalk is actually the casings of ancient algae. The algae gave their cases a type of "surface coating" to make them resistant to water. And it is probably this surface coating that we can see in action here, even 60 million years later' according to Ass. Prof. Hassenkam.

If we can manage to squeeze even a few percent more oil out of the seabed under the North Sea it could be worth millions of Danish crowns (DKK) for Denmark. Therefore Mærsk Oil and Gas AS on behalf of DUC (Dansk Undergrunds Consortium) along with Danish National Advanced Technology Foundation are supporting a project being carried out by Professor Susan Stipps' research group - the so-called Nano-Chalk Venture, which has been ongoing for the last two years. Tue Hassenkam originally became interested in chalk because he found the algae casings so beautiful. Today, after a year's work in front of a microscope, he is glad that his work also has a practical application. An understanding of how the oil clings to the chalk can possibly help develop a method to release it. And that will be the second part of the Nano-Chalk Venture.

Biofuels such as ethanol offer an alternative to petroleum for powering our cars, but growing energy crops to produce them can compete with food crops for farmland, and clearing forests to expand farmland will aggravate the climate change problem. How can we maximize our "miles per acre" from biomass? Researchers writing in the online edition of the May 7 Science magazine say the best bet is to convert the biomass to electricity, rather than ethanol. They calculate that, compared to ethanol used for internal combustion engines, bioelectricity used for battery-powered vehicles would deliver an average of 80% more miles of transportation per acre of crops, while also providing double the greenhouse gas offsets to mitigate climate change. "It's a relatively obvious question once you ask it, but nobody had really asked it before," says study co-author Chris Field, director of the Department of Global Ecology at the Carnegie Institution. "The kinds of motivations that have driven people to think about developing ethanol as a vehicle fuel have been somewhat different from those that have been motivating people to think about battery electric vehicles, but the overlap is in the area of maximizing efficiency and minimizing adverse impacts on climate."

Field, who is also a professor of biology at Stanford University and a senior fellow at Stanford's Woods Institute for the Environment, is part of a research team that includes lead author Elliott Campbell of the University of California, Merced, and David Lobell of Stanford's Program on Food Security and the Environment. The researchers performed a life-cycle analysis of both bioelectricity and ethanol technologies, taking into account not only the energy produced by each technology, but also the energy consumed in producing the vehicles and fuels. For the analysis, they used publicly available data on vehicle efficiencies from the US Environmental Protection Agency and other organizations.

Bioelectricity was the clear winner in the transportation-miles-per-acre comparison, regardless of whether the energy was produced from corn or from switchgrass, a cellulose-based energy crop. For example, a small SUV powered by bioelectricity could travel nearly 14,000 highway miles on the net energy produced from an acre of switchgrass, while a comparable internal combustion vehicle could only travel about 9,000 miles on the highway. (Average mileage for both city and highway driving would be 15,000 miles for a biolelectric SUV and 8,000 miles for an internal combustion vehicle.) "The internal combustion engine just isn't very efficient, especially when compared to electric vehicles," says Campbell. "Even the best ethanol-producing technologies with hybrid vehicles aren't enough to overcome this."

The researchers found that bioelectricity and ethanol also differed in their potential impact on climate change. "Some approaches to bioenergy can make climate change worse, but other limited approaches can help fight climate change," says Campbell. "For these beneficial approaches, we could do more to fight climate change by making electricity than making ethanol." The energy from an acre of switchgrass used to power an electric vehicle would prevent or offset the release of up to 10 tons of CO2 per acre, relative to a similar-sized gasoline-powered car. Across vehicle types and different crops, this offset averages more than 100% larger for the bioelectricity than for the ethanol pathway. Bioelectricity also offers more possibilities for reducing greenhouse gas emissions through measures such as carbon capture and sequestration, which could be implemented at biomass power stations but not individual internal combustion vehicles. While the results of the study clearly favor bioelectricity over ethanol, the researchers caution that the issues facing society in choosing an energy strategy are complex. "We found that converting biomass to electricity rather than ethanol makes the most sense for two policy-relevant issues: transportation and climate," says Lobell. "But we also need to compare these options for other issues like water consumption, air pollution, and economic costs." "There is a big strategic decision our country and others are making: whether to encourage development of vehicles that run on ethanol or electricity," says Campbell. "Studies like ours could be used to ensure that the alternative energy pathways we chose will provide the most transportation energy and the least climate change impacts."

Beef farmers can breathe easier thanks to University of Alberta researchers who have developed a formula to reduce methane gas in cattle. By developing equations that balance starch, sugar, cellulose, ash, fat and other elements of feed, a Canada-wide team of scientists has given beef producers the tools to lessen the methane gas their cattle produce by as much as 25 per cent. "That's good news for the environment," said Stephen Moore, a professor of agricultural, food and nutritional science at the University of Alberta in Canada. "Methane is a greenhouse gas, and in Canada, cattle account for 72 per cent of the total emissions. By identifying factors such as diet or genetics that can reduce emissions, we hope to give beef farmers a way to lessen the environmental footprint of their cattle production and methane reductions in the order of 25 per cent are certainly achievable." Using information from previous studies, the researchers compiled an extensive database of methane production values measured on cattle and were able to formulate equations to predict how much methane a cow would produce based on diet.

The study was jointly conducted with the universities of Guelph and Manitoba, Agriculture and Agri-Food Canada and the International Atomic Energy Agency in Austria. It published recently in the Journal of Animal Science. The findings build on previous work by Moore and his research team on genetically selecting cattle that inherently produce less methane. While further studies are needed before bringing the research into general use, the work "promises significant improvements in environmental stewardship on the farm," Moore noted.

America's power grid today resembles the country's canal system of the 19th Century. A marvel of engineering for its time, the canal system eventually could not keep pace with the growing demands of transcontinental transportation.

More than 150 years later, America's infrastructure is again changing in ways that its designers never anticipated. Distributed and intermittent electricity generation, such as wind power, is rapidly expanding, new smart meters are giving consumers more control over their energy usage, and plug-in hybrid electric vehicles may someday radically increase the overall demand for electricity. The evolution of America's energy needs has forced scientists and engineers to re-examine the operations, efficiency and security of the national power grid. The creation of a more secure and efficient national power grid requires significant innovations in the way we transmit electricity and monitor its use.

To better assess the challenges facing the power grid, the U.S. Department of Energy's (DOE) Argonne National Laboratory hosted a workshop that brought together power system and modeling experts from federal agencies, national laboratories and academia. "Modeling and simulation have proved to be effective tools for the power industry on many levels," said Mark Petri, Argonne's technology development director and one of the workshop's organizers. "We need to develop a comprehensive and integrated approach that will enable us to better understand the full implications of an evolving power grid as we plan for future demand and power sources." The workshop centered on the need for new methods to simulate the national power grid by modeling the creation and flow of electric power as well as the grid's connection to other critical infrastructures, such as transportation, gas, water and communications. Through detailed simulations of how electric power is supplied and transferred around the country, researchers can bolster not only the grid's security but also its reliability, efficiency and resiliency. "Implementing smart grid technologies on a large scale will not be trivial," Petri added. "The challenges go beyond technical and economic issues. The smart grid technologies could fundamentally change how national power grid systems operate and respond to disruptions."

Because of the great diversity of ways in which electricity is created, distributed and consumed, engineers face a challenge in creating reliable models of large power networks. They have to deal with the intermittent nature of some of the sources (like wind or solar), optimize how power is transmitted and balance economic, security and environmental priorities when finding solutions. "In the short-term," Petri said, "these simulations could help devise ways to solve the problem of grid congestion, which currently costs consumers many hundreds of millions of dollars each year. Even small improvements in grid efficiency that better models and simulations would produce would make the investment cost-effective."

The workshop, which was sponsored by U.S. Department of Homeland Security Science and Technology Directorate, identified barriers that a national grid simulation capability would need to overcome to be effective. The findings of the workshop appear in the report "National Power Grid Simulation Capability: Needs and Issues." According to Petri, an operational plan for a national power grid simulation capability that engages industry to better understand their needs, capabilities and concerns would support a more secure and reliable electric power grid system for the future.

Trees positioned to shade the west and south sides of a house may decrease summertime electric bills by 5 percent on average, according to a recent study* of California homes by researchers from the National Institute of Standards and Technology (NIST) and the U.S. Department of Agriculture (USDA). The first large-scale study of its kind, the research paper considers the effects of shade on 460 single-family homes in Sacramento during the summer of 2007 and provides hard statistics showing how well-placed shade trees can reduce energy costs and atmospheric carbon, as well. "People have known for a long time that trees have multiple benefits for people, but we've quantified one of them for the first time using actual billing data and put a dollar value on it," said NIST's David Butry, who authored the paper with Geoffrey Donovan of the USDA Forest Service's Pacific Northwest Research Station.

The study's findings included: · Planting trees on the west and south sides of a house decreased summertime electricity use, but planting them on the north actually increased it. Those on the east had no effect. · Fast-growing trees provide better help than do smaller ones, and placement of the trees, particularly the distance from the house, is a significant factor. · A London plane tree, planted on the west side of a house, can reduce carbon emissions from summertime electricity use by an average of 31 percent over 100 years. This last finding was particularly significant to Butry, who said that trees not only reduce the carbon produced by the local gas or coal-fired power generator, but also remove carbon dioxide-a greenhouse gas-from the atmosphere.

"Trees sequester carbon in addition to providing shade," Butry said. "We measured how much these shade trees reduced the carbon created by burning fuels to produce the electricity, and found that the trees also sequestered an equivalent amount of carbon on top of that. So there's a double benefit." Utility companies from as far away as South Korea and South Africa have contacted the team about expanding the study, which was limited to a single season in a single city. "It would be really interesting to look at how the effect varies across regions of the U.S. and of the world, and to see what happens in wintertime," Butry said. "Sacramento Municipal Utility was very helpful in providing us with the data we needed. But future studies will depend on who has data and shares it with us."

* G.H. Donovan and D.T. Butry. The value of shade: Estimating the effect of urban trees on summertime electricity use. Energy and Buildings June, 2009, 662-668. doi: 10.1016/j.enbuild.2009.01.002

Researchers have developed a technique that uses sensors and computational software to constantly monitor forces exerted on wind turbine blades, a step toward improving efficiency by adjusting for rapidly changing wind conditions. The research by engineers at Purdue University and Sandia National Laboratories is part of an effort to develop a smarter wind turbine structure "The ultimate goal is to feed information from sensors into an active control system that precisely adjusts components to optimize efficiency," said Purdue doctoral student Jonathan White, who is leading the research with Douglas Adams, a professor of mechanical engineering and director of Purdue's Center for Systems Integrity. The system also could help improve wind turbine reliability by providing critical real-time information to the control system to prevent catastrophic wind turbine damage from high winds. "Wind energy is playing an increasing role in providing electrical power," Adams said. "The United States is now the largest harvester of wind energy in the world. The question is, what can be done to wind turbines to make them more efficient, more cost effective and more reliable?"

The engineers embedded sensors called uniaxial and triaxial accelerometers inside a wind turbine blade as the blade was being built. The blade is now being tested on a research wind turbine at the U.S. Department of Agriculture's Agriculture Research Service laboratory in Bushland, Texas. Personnel from Sandia and the USDA operate the research wind turbines at the Texas site. Such sensors could be instrumental in future turbine blades that have "control surfaces" and simple flaps like those on an airplane's wings to change the aerodynamic characteristics of the blades for better control. Because these flaps would be changed in real time to respond to changing winds, constant sensor data would be critical. "This is a perfect example of a partnership between a national lab and an academic institution to develop innovations by leveraging the expertise of both," said Jose R. Zayas, manager of Sandia's Wind Energy Technology Department.

Research findings show that using a trio of sensors and "estimator model" software developed by White accurately reveals how much force is being exerted on the blades. Purdue and Sandia have applied for a provisional patent on the technique. Findings are detailed in a paper being presented Monday (May 4) during the Windpower 2009 Conference & Exhibition in Chicago. The paper was written by White, Adams and Sandia engineer Mark A. Rumsey and Zayas. The four-day conference, organized by the American Wind Energy Association, attracts thousands of attendees and is geared toward industry. "Industry is most interested in identifying loads, or forces, exerted on turbine blades and predicting fatigue, and this work is a step toward accomplishing that," White said. A wind turbine's major components include rotor blades, a gearbox and generator. The wind turbine blades are made primarily of fiberglass and balsa wood and occasionally are strengthened with carbon fiber.

"The aim is to operate the generator and the turbine in the most efficient way, but this is difficult because wind speeds fluctuate," Adams said. "You want to be able to control the generator or the pitch of the blades to optimize energy capture by reducing forces on the components in the wind turbine during excessively high winds and increase the loads during low winds. In addition to improving efficiency, this should help improve reliability. The wind turbine towers can be 200 feet tall or more, so it is very expensive to service and repair damaged components." Sensor data in a smart system might be used to better control the turbine speed by automatically adjusting the blade pitch while also commanding the generator to take corrective steps. "We envision smart systems being a potentially huge step forward for turbines," said Sandia's Rumsey. "There is still a lot of work to be done, but we believe the payoff will be great. Our goal is to provide the electric utility industry with a reliable and efficient product. We are laying the groundwork for the wind turbine of the future."

Sensor data also will be used to design more resilient blades. The sensors are capable of measuring acceleration occurring in various directions, which is necessary to accurately characterize the blade's bending and twisting and small vibrations near the tip that eventually cause fatigue and possible failure. The sensors also measure two types of acceleration. One type, the dynamic acceleration, results from gusting winds, while the other, called static acceleration, results from gravity and the steady background winds. It is essential to accurately measure both forms of acceleration to estimate forces exerted on the blades. The sensor data reveal precisely how much a blade bends and twists from winds. The research is ongoing, and the engineers are now pursuing the application of their system to advanced, next-generation turbine blades that are more curved than conventional blades. This more complex shape makes it more challenging to apply the technique. In 2008 the United States added 8,358 megawatts of new wind-power capacity, which equates to thousands of new turbines since the average wind turbine generates 1.5 megawatts. The new capacity increased the total U.S. installed wind power to 25,170 megawatts, surpassing Germany's capacity as the world's largest harvester of wind power.

"Our aim is to do two things - improve reliability and prevent failure - and the most direct way to enable those two capabilities is by monitoring forces exerted on the blades by winds," Adams said.

Glaciers in the Southern Hemisphere are growing out of step with those in the North The vast majority of the world's glaciers are retreating as the planet gets warmer. But a few, including glaciers south of the equator in South America and New Zealand, are inching forward. A paper in this week's issue of the journal Science puts this enigma in perspective; for the last 7,000 years, New Zealand's largest glaciers have often moved out of step with glaciers in the Northern Hemisphere, pointing to strong regional variations in climate. "This research should provide much more accurate reconstructions of glacial advances worldwide, allowing us in turn to make climate models more accurate," said Paul Filmer, program director in the National Science Foundation's (NSF) Division of Earth Sciences, which funded the research.

Conventional wisdom holds that during the era of human civilization, climate has been relatively stable. The new study is the latest to challenge this view, by showing that New Zealand's glaciers have gone through rapid periods of growth and decline during the current interglacial period known as the Holocene. "New Zealand's mountain glaciers have fluctuated frequently over the last 7,000 years, and glacial advances have become slightly smaller through time," said Joerg Schaefer, lead author of the paper and a geochemist at Columbia University's Lamont-Doherty Earth Observatory. "This pattern differs in important ways from the northern hemisphere glaciers. The door is open now towards a global map of Holocene [a geological time period that began about 11,700 years ago and continues to the present] glacier fluctuations and how climate variations during this period impacted human civilizations."

Glaciers are extremely sensitive to changes in temperature and snowfall, which makes them well suited for studying past climate. This archive has been largely untapped, however, because of the difficulty in assigning precise ages to glacier fluctuations. One way to measure glacial fluxes is by studying the moraines, or rock deposits that glaciers often leave behind at their maximum points of advance. However, until now the methods of dating such moraines, including radiocarbon dating of organic matter, could be off by hundreds of years. By refining the analysis of a method called cosmogenic dating, Schaefer and colleagues were able for the first time to assign precise ages to young Holocene moraines. They accomplished this by measuring minute levels of the chemical isotope beryllium 10 in the rocks, which is produced when cosmic rays strike rock surfaces, and builds up over time. The researchers were thus able to pinpoint exactly when glaciers in New Zealand's Southern Alps began to recede, exposing the rocks to the cosmic rays.

From the results, they constructed a glacial timeline for the past 7,000 years and compared it against historic records from the Swiss Alps and other places north of the equator. They found that within that timeframe, the glaciers around Mount Cook, New Zealand's highest peak, reached their largest extent about 6,500 years ago, when the Swiss Alps and Scandinavia were relatively warm. That's about 6,000 years before northern glaciers hit their Holocene peak during the Little Ice Age, between 1300 and 1860 AD. That finding was a surprise to some scientists who assumed that the northern cold phase happened globally. The record in New Zealand shows other disparities that point to regional climate variations in both hemispheres. The new chemical and analytical protocols are expected to allow scientists to accurately date glacier fluctuations throughout the Holocene, rounding out the climate picture on the continents. "With this measure we can go to almost any mountain range on earth and date the moraines in front of the glaciers and produce a similar chronology," said co-author George Denton, a glaciologist at the University of Maine and an adjunct scientist at Lamont-Doherty.

Overall, glaciers around the world have been declining since about 1860, with the exception of a brief advance in Switzerland in the 1980s, New Zealand in the late 1970s through today, and a few other places. Changes in wind and sea surface temperatures are thought to be causing these regional fluctuations. Currently in a wet phase, New Zealand is expected to swing back to a warmer, drier phase in the next few years, causing the glaciers to retreat once again.

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