In a pioneering use of computed tomography (CT) scans, researchers at Woods Hole Oceanographic Institution (WHOI) have discovered that carbon dioxide (CO2)-induced global warming is in the process of killing off a major coral species in the Red Sea. As summer sea surface temperatures have remained about 1.5 degrees Celsius above ambient over the last 10 years, growth of the coral, Diploastrea heliopora, has declined by 30% and "could cease growing altogether by 2070" or sooner, they report in the July 16 issue of the journal Science.
"The warming in the Red Sea and the resultant decline in the health of this coral is a clear regional impact of global warming," said Neal E. Cantin, a WHOI postdoctoral investigator and co-lead researcher on the project. In the 1980s, he said, "the average summer [water] temperatures were below 30 degrees Celsius. In 2008 they were approaching 31 degrees".
Cantin and WHOI Research Specialist Anne L. Cohen, the other lead investigator, said the findings were unexpected because D. heliopora did not exhibit one of the typical signs of thermal stress: bleaching. "These corals looked healthy," said Cohen.
But Computerized axial tomography scanning of the coral's skeletal structure in the laboratory revealed "the secrets that the skeletons are hiding," she said. "The Computerized axial tomography scans reveal that these corals have actually been under chronic stress for the last 10 years, and that the rates of growth were the lowest in 2008," the final year of the study.........
By 2039, most of the US could experience at least four seasons equally as intense as the hottest season ever recorded from 1951-1999, according to Stanford University climate scientists. In most of Utah, Colorado, Arizona and New Mexico, the number of extremely hot seasons could be as high as seven.
Credit: Noah Diffenbaugh, Stanford University
Exceptionally long heat waves and other hot events could become commonplace in the United States in the next 30 years, as per a newly released study by Stanford University climate scientists.
"Using a large suite of climate model experiments, we see a clear emergence of much more intense, hot conditions in the U.S. within the next three decades," said Noah Diffenbaugh, an assistant professor of environmental Earth system science at Stanford and the main author of the study.
Writing in the journal Geophysical Research Letters (GRL), Diffenbaugh concluded that hot temperature extremes could become frequent events in the U.S. by 2039, posing serious risks to agriculture and human health.
"In the next 30 years, we could see an increase in heat waves like the one now occurring in the eastern United States or the kind that swept across Europe in 2003 that caused tens of thousands of fatalities," said Diffenbaugh, a center fellow at Stanford's Woods Institute for the Environment. "Those kinds of severe heat events also put enormous stress on major crops like corn, soybean, cotton and wine grapes, causing a significant reduction in yields".
The GRL study took two years to complete and is co-authored by Moetasim Ashfaq, a former Stanford postdoctoral fellow now at the Oak Ridge National Laboratory. The study comes on the heels of a recent NASA report, which concluded that the prior decade, January 2000 to December 2009, was the warmest on record.........
Metallic carbon nanotubes show great promise for applications from microelectronics to power lines because of their ballistic transmission of electrons. But who knew magnets could stop those electrons in their tracks?
Rice physicist Junichiro Kono and his team have been studying the Aharonov-Bohm effect -- the interaction between electrically charged particles and magnetic fields -- and how it relates to carbon nanotubes. While doing so, they came to the unexpected conclusion that magnetic fields can turn highly conductive nanotubes into semiconductors.
Their findings are published online this month in Physical Review Letters.
"When you apply a magnetic field, a band gap opens up and it becomes an insulator," said Kono, a Rice professor in electrical and computer engineering and in physics and astronomy. "You are changing a conductor into a semiconductor, and you can switch between the two. So this experiment explores both an important aspect of the results of the Aharonov-Bohm effect and the novel magnetic properties of carbon nanotubes".
Kono, graduate student Thomas Searles and their colleagues at the National Institute of Standards and Technology (NIST) and in Japan successfully measured the magnetic susceptibility of a variety of nanotubes for the first time; they confirmed that metallics are far more susceptible to magnetic fields than semiconducting nanotubes, depending upon the orientation and strength of the field.........
Longrich named the newly discovered dinosaur species Mojoceratops after its flamboyant, heart-shaped skull. (Photo: Nicholas Longrich)
When Nicholas Longrich discovered a new dinosaur species with a heart-shaped frill on its head, he wanted to come up with a name just as flamboyant as the dinosaur's appearance. Over a few beers with fellow paleontologists one night, he blurted out the first thing that came to mind: Mojoceratops.
"It was just a joke, but then everyone stopped and looked at each other and said, 'Wait - that actually sounds cool,' " said Longrich, a postdoctoral associate at Yale University. "I tried to come up with serious names after that, but Mojoceratops just sort of stuck".
With the publication of Longrich's paper describing his find in the Journal of Paleontology, online today, the name is now official.
The dinosaur is one of more than a dozen species belonging to the chasmosaurine ceratopsid family, which are defined by elaborate frills on their skulls. A plant eater about the size of a hippopotamus, Mojoceratops appeared about 75 million years ago during the Late Cretaceous - 10 million years earlier than its well-known cousin, the Triceratops. The species, which is correlation to another dinosaur in Texas, is found only in Canada's Alberta and Saskatchewan provinces and was short-lived, having survived for only about one million years.
It was only after coming up with the unusual name that Longrich looked into its etymology. Surprisingly, he observed that it was a perfect fit for the species, which sported a flamboyant, heart-shaped frill on its head.........
With the attention of sports fans worldwide focused on South Africa and the 2010 FIFA World Cup, U.S. scientist John Eric Goff has made the aerodynamics of the soccer ball a focus of his research.
In an article appearing in the magazine Physics Today this month, Goff examines the science of soccer and explains how the world's greatest players are able to make a soccer ball do things that would seem to defy the forces of nature.
Goff's article looks at the ball's changing design and how its surface roughness and asymmetric air forces contribute to its path once it leaves a player's foot. His analysis leads to an understanding of how reduced air density in games played at higher altitudes -- like those in South Africa -- can contribute to some of the jaw-dropping ball trajectories already seen in some of this year's matches.
"The ball is moving a little faster than what some of the players are used to," says Goff, who is a professor of physics at Lynchburg College in Virginia and an expert in sports science.
For Goff, soccer is a sport that offers more than non-stop action -- it is a living laboratory where physics equations are continuously expressed. On the fields of worldwide competition, the balls maneuver as per complicated formulae, he says, but these can be explained in terms the average viewer can easily understand. And the outcomes of miraculous plays can be explained simply in terms of the underlying physics.........
Man-made global warming started with ancient hunters
Even before the dawn of agriculture, people may have caused the planet to warm up, a newly released study suggests.
Mammoths used to roam modern-day Russia and North America, but are now extinct-and there's evidence that around 15,000 years ago, early hunters had a hand in wiping them out. A newly released study, accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union (AGU), argues that this die-off had the side effect of heating up the planet.
"A lot of people still believe that people are unable to affect the climate even now, even when there are more than 6 billion people," says the main author of the study, Chris Doughty of the Carnegie Institution for Science in Stanford, California. The new results, however, "show that even when we had populations orders of magnitude smaller than we do now, we still had a big impact".
In the newly released study, Doughty, Adam Wolf, and Chris Field-all at Carnegie Institution for Science-propose a scenario to explain how hunters could have triggered global warming.
First, mammoth populations began to drop-both because of natural climate change as the planet emerged from the last ice age, and because of human hunting. Normally, mammoths would have grazed down any birch that grew, so the area stayed a grassland. But if the mammoths vanished, the birch could spread. In the cold of the far north, these trees would be dwarfs, only about 2 meters (6 feet) tall. Nonetheless, they would dominate the grasses.........
Extinction of woolly mammoth and saber-toothed cat
A new analysis of the extinction of woolly mammoths and other large mammals more than 10,000 years ago suggests that they may have fallen victim to the same type of "trophic cascade" of ecosystem disruption that researchers say is being caused today by the global decline of predators such as wolves, cougars, and sharks.
In each case the cascading events were originally begun by human disruption of ecosystems, a newly released study concludes, but around 15,000 years ago the problem was not the loss of a key predator, but the addition of one human hunters with spears.
In a study published recently in the journal BioScience, scientists propose that this mass extinction was caused by newly-arrived humans tipping the balance of power and competing with major predators such as saber-toothed cats. An equilibrium that had survived for thousands of years was disrupted, possibly explaining the loss of two-thirds of North America's large mammals during this period.
"For decades, researchers have been debating the causes of this mass extinction, and the two theories with the most support are hunting pressures from the arrival of humans, and climate change," said William Ripple, a professor of forest ecosystems and society at Oregon State University, and an expert on the ecosystem alterations that researchers are increasingly finding when predators are added or removed.........
A DOE study will test the impact of increased temperature on Arctic tundra (photo provided by researcher Stan Wullschleger).
Researchers at the Department of Energy's Oak Ridge National Laboratory are planning a large-scale, long-term ecosystem experiment to test the effects of global warming on the icy layers of arctic permafrost.
While ORNL scientists have conducted extensive studies on the impact of climate change in temperate regions like East Tennessee, less is known about the impact global warming could have on arctic regions.
"We're beginning to take these lessons learned and start applying them to sensitive and globally important ecosystems, such as the arctic," said Stan Wullschleger of the Environmental Sciences Division. "The arctic regions are important to the topic of global warming because of the large land area they occupy around the world and the layer of permanently frozen soil, known according tomafrost."
Wullschleger and a team of architects, engineers and biologists from ORNL and other national laboratories design, simulate using computers and then field test large-scale manipulative experiments that purposely warm a test area in order to evaluate ecosystem response to projected climate conditions.
"Evidence is emerging that the arctic is experiencing a greater degree of warming than the rest of the globe," Wullschleger said. "There is growing concern that this warming is already affecting a wide range of physical and ecological processes in the arctic, including permafrost degradation. Manipulative experiments will help us study these processes and their consequences in great detail."........
Atomic Force Microscopy to Study Subsurface Structures
Electric force microscopy can be used to detail structures well below the surface. Left, AFM height image showing the surface of a polyimide/carbon nanotube composite. Right, EFM image revealing the curved lines of subsurface nanotubes.
Credit: NIST
Over the past couple of decades, atomic force microscopy (AFM) has emerged as a powerful tool for imaging surfaces at astonishing resolutions-fractions of a nanometer in some cases. But suppose you're more concerned with what lies below the surface? Scientists at the National Institute of Standards and Technology (NIST) have shown that under the right circumstances, surface science instruments such as the AFM can deliver valuable data about sub-surface conditions.
Their recently published* work with colleagues from the National Aeronautics and Space Administration (NASA), National Institute of Aerospace, University of Virginia and University of Missouri could be especially useful in the design and manufacture of nanostructured composite materials. Engineers are studying advanced materials that mix carbon nanotubes in a polymer base for a wide variety of high-performance applications because of the unique properties, such as superior strength and electrical conductance, added by the nanotubes. The material chosen by the research team as their test case, for example, is being studied by NASA for use in spacecraft actuators because it may outperform the heavier ceramics now used.
But, says NIST materials scientist Minhua Zhao, "one of the critical issues to study is how the carbon nanotubes are distributed within the composite without actually breaking the part. There are very few techniques available for this kind of non-destructive study." Zhao and colleagues decided to try an unusual application of atomic force microscopy.........
The prototype of Hamelinck's mirror system in one of its assembly steps. Photo: Roger Hamelinck
A sharp view of the starry sky is difficult, because the atmosphere constantly distorts the image. TU/e researcher Roger Hamelinck developed a new type of telescope mirror, which quickly corrects the image. His prototypes are mandatory for future large telescopes, but also gives old telescopes a sharper view.
The atmosphere contains 'bubbles' of hot and cold air, each with their own refractive index, which distort the image. As a result, the light reaching ground-based telescopes is distorted. Hamelinck's system tackles this problem with a deformable mirror in the telescope. Under this ultrathin mirror there are actuators, which can wherever necessary quickly create bumps and dimples in the mirror. These bumps and dimples correct the continuously changing distortion created in the atmosphere. This is of crucial importance to the new generation of large telescopes in particular. Hamelinck: "In principle, larger telescopes also have a higher resolution, but attaining an optimal optical quality is hampered by the atmosphere. Therefore you absolutely need these corrections."
Modular
The principle of the 'adaptive deformable mirror' has been known some fifty odd years, but was limited particularly by the technology. Thus, the actuators of earlier systems generated much heat, which caused the systems themselves to become a source of distortion. "Contrary to the old systems, this new system has an ultrathin mirror, so that very little power is needed for its deformation ", Hamelinck explains. "In combination with the efficient, electromagnetic reluctance actuators, this reduces the heat generation of the system to a very low level. Thanks to this, no active cooling is required." Hamelinck's working prototype has a five-centimeter diameter. Given that the design is scalable and expandable with modules, the system is suited for very large telescopes, such as the future 42-meter-big E-ELT (European Extra Large Telescope). The E-ELT is fitted inter alia with an adaptive mirror of 2.4 meters.........
A critical minimum for Arctic sea ice can also be expected for late summer 2010. Researchers from the German "Alfred Wegener Institute for Polar and Marine Research in the Helmholtz Association (AWI)" in Bremerhaven and from "KlimaCampus" of the University of Hamburg have now published their projections in the current Sea Ice Outlook. The online publication compares the forecasts on ice cover for September 2010 prepared by around a dozen international research institutes in a scientific "competition". The ice reaches its minimum area at this time every year.
The forecast developed by the team from KlimaCampus of the University of Hamburg, i.e. 4.7 million square kilometres (km2), is more negative than that submitted by the AWI researchers, who arrived at a figure of 5.2 million km2. Nevertheless, neither of the two research groups anticipates that the record minimum of 4.3 million km2 in 2007 will be reached.
Eventhough Arctic ice currently has an area of ten million km2, which is half a million km2 smaller than in 2007, one cannot directly conclude a new record minimum in late summer. The present ice cover is comparable to that in June 2006, a year when more ice area remained in September than in 2007. The decisive factors for the situation in late summer, such as the ice thickness in the central Arctic and further development of the weather in summer, are still not known, however.........
The photoemission of electrons by an attosecond light pulse (blue beam) is time resolved by controlling the electron motion with an ultrashort visible laser pulse (shown as red beam). This attosecond streaking uncovers that electrons from different atomic orbitals are released with a delay comparable to the atomic unit of time.
Credit: Photograph: Thorsten Naeser / Max-Planck-Institute of Quantum Optics
When light is absorbed by atoms, the electrons become excited. If the light particles, so-called photons, carry sufficient energy, the electrons can be ejected from the atom. This effect is known as photoemission and was explained by Einstein more than hundred years ago. Until now, it has been assumed that the electron start moving out of the atom immediately after the impact of the photon. This point in time can be detected and has so far been considered as coincident with the arrival time of the light pulse, i.e. with "time zero" in the interaction of light with matter.
Using their ultra-short time measurement technology, physicists from the Laboratory for Attosecond Physics at the Max Planck Institute of Quantum Optics (MPQ), the Technische Universitaet Muenchen (TUM) and the Ludwig-Maximilians-Universitaet Munich (LMU) along with collaborators from Austria, Greece, and Saudi Arabia, have now tested this assumption.
The physicists fired pulses of near-infrared laser light lasting less than four femtoseconds (10-15 seconds) at atoms of the noble gas neon. The atoms were simultaneously hit by extreme ultraviolet pulses with a duration of 180 attoseconds, liberating electrons from their atomic orbitals. The attosecond flashes ejected electrons either from the outer 2p-orbitals or from the inner 2s-orbitals of the atom. With the controlled field of the synchronised laser pulse serving as an "attosecond chronograph", the physicists then recorded when the excited electrons left the atom.........
The approach the U.S. Environmental Protection Agency (EPA) uses to estimate greenhouse gas emissions from agricultural anaerobic lagoons that treat manure contains errors and may underestimate methane emissions by up to 65%, as per researchers from the University of Missouri.
Anaerobic lagoons treat manure on some animal feeding operations previous to application to crops as a fertilizer. Methane, one byproduct of the therapy process, has 21 times the warming potential of carbon dioxide.
A 2007 U.S. Supreme Court ruling mandated the EPA consider greenhouse gases a pollutant. This led the EPA in 2009 to approve greenhouse gas reporting requirements for any facility that annually releases 25,000 metric tons or more of carbon dioxide equivalents to the atmosphere. The objective of these reporting requirements is to quantify emissions as a first step towards developing strategies to reduce greenhouse gas losses.
Direct measurements of methane emissions from anaerobic lagoons are technically difficult and very expensive, so the EPA adopted a calculation method to estimate methane emissions from anaerobic digesters. They relied on the method used by the International Panel on Climate Change (IPCC) in their 2006 worldwide estimate of greenhouse inventories.........
The bacterium Micrococcus luteus harbors a three-gene cluster that encodes for enzymes essential to the synthesis of alkenes.
If concerns for global climate change and ever-increasing costs weren't enough, the disastrous Gulf oil spill makes an even more compelling case for the development of transportation fuels that are renewable, can be produced in a sustainable fashion, and do not put the environment at risk. Liquid fuels derived from plant biomass have the potential to be used as direct replacements for gasoline, diesel and jet fuels if cost-effective means of commercial production can be found.
Scientists with the U.S. Department of Energy (DOE)'s Joint BioEnergy Institute (JBEI) have identified a trio of bacterial enzymes that can catalyze key steps in the conversion of plant sugars into hydrocarbon compounds for the production of green transportation fuels.
Harry Beller, an environmental microbiologist who directs the Biofuels Pathways department for JBEI's Fuels Synthesis Division, led a study in which a three-gene cluster from the bacterium Micrococcus luteus was introduced into the bacterium Escherichia coli. The enzymes produced by this trio of genes enabled the E. coli to synthesize from glucose long-chain alkene hydrocarbons. These long-chain alkenes can then be reduced in size - a process called "cracking" - to obtain shorter hydrocarbons that are compatible with today's engines and favored for the production of advanced lignocellulosic biofuels.........
A close-up of the tooth marks gouged in the rib bone of a large dinosaur by a mammal that lived 75 million years ago. (Photo: Nicholas Longrich/Yale University)
Paleontologists have discovered the oldest mammalian tooth marks yet on the bones of ancient animals, including several large dinosaurs. They report their findings in a paper published online June 16 in the journal Paleontology.
Nicholas Longrich of Yale University and Michael J. Ryan of the Cleveland Museum of Natural History came across several of the bones while studying the collections of the University of Alberta Laboratory for Vertebrate Palaeontology and the Royal Tyrrell Museum of Palaeontology. They also found additional bones displaying tooth marks during fieldwork in Alberta, Canada. The bones are all from the Late Cretaceous epoch and date back about 75 million years.
The pair discovered tooth marks on a femur bone from a Champsosaurus, an aquatic reptile that grew up to five feet long; the rib of a dinosaur, most likely a hadrosaurid or ceratopsid; the femur of another large dinosaur that was likely an ornithischian; and a lower jaw bone from a small marsupial.
The scientists believe the marks were made by mammals because they were created by opposing pairs of teeth-a trait seen only in mammals from that time. They think they were most likely made by multituberculates, an extinct order of archaic mammals that resemble rodents and had paired upper and lower incisors. Several of the bones display multiple, overlapping bites made along the curve of the bone, revealing a pattern similar to the way people eat corn on the cob.........
As turboprop and jet aircraft climb or descend under certain atmospheric conditions, they can inadvertently seed mid-level clouds and cause narrow bands of snow or rain to develop and fall to the ground, new research finds. Through this seeding process, they leave behind odd-shaped holes or channels in the clouds, which have long fascinated the public.
The key ingredient for developing these holes in the clouds: water droplets at subfreezing temperatures, below about 5 degrees Fahrenheit (-15 degrees Celsius). As air is cooled behind aircraft propellers or over jet wings, the water droplets freeze and drop toward Earth.
"Any time aircraft fly through these specific conditions, they are altering the clouds in a way that can result in enhanced precipitation nearby," says Andrew Heymsfield, a scientist with the National Center for Atmospheric Research (NCAR) and main author of a newly released study into the phenomenon. "Just by flying an airplane through these clouds, you could produce as much precipitation as with seeding materials along the same path in the cloud".
Precipitation from planes appears to be especially common in regions such as the Pacific Northwest and western Europe because of the frequent occurrence of cloud layers with supercooled droplets, Heymsfield says.........
Large majority of Americans still believe in global warming
Three out of four Americans think that the Earth has been gradually warming as the result of human activity and want the government to institute regulations to stop it, as per a new survey by scientists at the Woods Institute for the Environment at Stanford University.
The survey was conducted by Woods Institute Senior Fellow Jon Krosnick, a professor of communication and of political science at Stanford, with funding from the National Science Foundation. The results are based on telephone interviews conducted from June 1-7 with 1,000 randomly selected American adults.
"Several national surveys released during the last eight months have been interpreted as showing that fewer and fewer Americans think that climate change is real, human-caused and threatening to people," Krosnick said. "But our new survey shows just the opposite".
For example, when respondents in the June 2010 survey were asked if the Earth's temperature probably had been heating up over the last 100 years, 74 percent said yes. And 75 percent said that human behavior was substantially responsible for any warming that has occurred. Krosnick has asked similar questions in prior Woods Institute polls since 2006.
"Our surveys reveal a small decline in the proportion of people who believe global warming has been happening, from 84 percent in 2007 to 74 percent today," Krosnick said. "Statistical analysis of our data revealed that this decline is attributable to perceptions of recent weather changes by the minority of Americans who have been skeptical about climate scientists".........
Oil from spill could have powered 38,000 cars for year
Sunlight illuminated the lingering oil slick off the Mississippi Delta on May 24, 2010. Image courtesy of NASA.
As of today (Wednesday, June 9), if all the oil from the Deepwater Horizon spill in the Gulf of Mexico had been used for fuel, it could have powered 38,000 cars, and 3,400 trucks, and 1,800 ships for a full year, as per University of Delaware Prof. James J. Corbett. That's based on the estimated spill rate of 19,000 barrels of oil per day.
Corbett, a professor of marine policy in UD's College of Earth, Ocean, and Environment, works on energy and environmental solutions for transportation. He has launched a website that reports the impact of the Deepwater Horizon oil spill in terms of lost uses of the lost fuel on a daily basis.
Visitors to the website can choose the spill rate they believe is most accurate from a range of reported estimates, and the website will automatically calculate how a number of cars, trucks, and ships could have been powered for a year, based on Bureau of Transportation Statistics.
Here are just a few of Corbett's findings:
By May 5 (15 days after the spill), the oil lost could have fueled 470 container ships serving New York and New Jersey ports for a year.
By May 25 (35 days after the spill), energy from the spilled oil could have provided a year's gasoline for all registered automobiles (about 26,000 cars) in Newark, Del., where UD's main campus is located.
Researchers are reporting a new technique for mapping and testing oil-contaminated soils. Traditionally, samples need to be collected from the field and returned to a lab for extensive chemical analysis, costing time and money when neither is readily available during a clean-up operation. The new method can take measurements in the field and accurately predict the total amount of petroleum contaminants in moist, unprepared soil samples.
The research team led was by soil researchers David Weindorf from Louisiana State University, Cristine Morgan of Texas Agrilife Research, and John Galbraith from Virginia Tech. The method they investigated used visible near infrared light with diffuse reflectance spectroscopy, shining a light on a sample and reading the reflecting wavelengths. This allowed the scientists to rapidly evaluate soils for the presence and amount of oil contamination quickly while in the field, without sending a sample to a laboratory and waiting for test results. The technique was used to predict total petroleum hydrocarbons in a variety of soils in southern Louisiana.
Results from the study were published in the July-August 2010 issue of the Journal of Environmental Quality, a publication of the American Society of Agronomy, the Crop Science Society of America, and the Soil Science Society of America. Funded by the Louisiana Applied Oil Spill Research Program, the research was also presented at Clean Gulf 2009 in New Orleans, LA and the 2009 Soil Science Society of America International Annual Meetings in Pittsburgh, PA.........
Public concern about global warming is once again on the rise, as per a national survey released recently by scientists at Yale and George Mason Universities. The results come as the U.S. Senate prepares to vote this week on a resolution to block the EPA from regulating carbon dioxide as a pollutant.
Since January, public belief that global warming is happening rose four points, to 61 percent, while belief that it is caused mostly by human activities rose three points, to 50 percent. The number of Americans who worry about global warming rose three points, to 53 percent. And the number of Americans who said that the issue is personally important to them rose five points, to 63 percent.
"The stabilization and slight rebound in public opinion is occurring amid signs the economy is starting to recover, along with consumer confidence, and as memories of unusual snowstorms and scientific scandals recede," said Anthony Leiserowitz, director of the Yale Project on Climate Change Communication. "The BP oil disaster is also reminding the public of the dark side of dependence on fossil fuels, which appears to be increasing support for clean energy policies".
Americans who said President Obama and Congress should make developing sources of clean energy a high priority increased 11 points, to 71 percent, while those who said that global warming should be a high priority rose six points, to 44 percent. In a seven-point increase since January, 69 percent of Americans said that the United States should make a large or medium effort to reduce global warming even if it incurs large or moderate economic costs.........
Global warming may present a threat to animal and plant life even in biodiversity hot spots once thought less likely to suffer from climate change, as per a newly released study from Rice University.
Research by Amy Dunham, a Rice assistant professor of ecology and evolutionary biology, detailed for the first time a direct connection between the frequency of El Nio and a threat to life in Madagascar, a tropical island that acts as a refuge for a number of unique species that exist nowhere else in the world. In this case, the lemur plays the role of the canary in the coal mine.
The study in the journal Global Change Biology is currently available online and will be included in an upcoming print issue.
Dunham said most studies of global warming focus on temperate zones. "We all know about the polar bears and their melting sea ice," she said. "But tropical regions are often thought of as refuges during past climate events, so they haven't been given as much attention until recently.
"We're starting to realize that not only are these hot spots of biodiversity facing habitat degradation and other anthropogenic effects, but they're also being affected by the same changes we feel in the temperate zones".
Dunham's interest in lemurs, which began as an undergraduate student at Connecticut College, resulted in a groundbreaking study last year that provided new insight into a long-standing mystery: Why male and female lemurs are the same size.........
Removing impurities on the atomic scale Engineering professor Vivek Shenoy (right) and graduate student Akbar Bagri have explored the atomic configuration of graphene oxide, showing how defects in graphene sheets can be located and treated. Credit: Mike Cohea/Brown University
Graphene, a carbon sheet that is one-atom thick, appears to be at the center of the next revolution in material science. These ultrathin sheets hold great potential for a variety of applications from replacing silicon in solar cells to cooling computer chips.
Despite its vast promise, graphene and its derivatives "are materials people understand little about," said Vivek Shenoy, professor of engineering at Brown University. "The more we can understand their properties, the more (technological) possibilities that will be opened to us".
Shenoy and a team of U.S. scientists have gained new insights into these mysterious materials. The team, in a paper in Nature Chemistry, pinpoints the atomic configurations of noncarbon atoms that create defects when graphene is produced through a technique called graphene-oxide reduction. Building from that discovery, the scientists propose how to make that technique more efficient by outlining precisely how to apply hydrogen - rather than heat - to remove impurities in the sheets.
The sheets produced by graphene-oxide reduction are two-dimensional, honeycomb-looking planes of carbon. Most of the atoms in the lattice are carbon, which is what researchers want. But interwoven in the structure are also oxygen and hydrogen atoms, which disrupt the uniformity of the sheet. Apply enough heat to the lattice, and some of those oxygen atoms bond with hydrogen atoms, which can be removed as water. But some oxygen atoms are more stubborn.........
Every minute, 10,000 gallons of water mysteriously gush out of the desert floor at a place called Ash Meadows, an oasis that is home to 24 plant and animal species found nowhere else in the world.
A new Brigham Young University study indicates that the water arriving at Ash Meadows is completing a 15,000-year journey, flowing slowly underground from what is now the Nevada Test Site.
The U.S. government tested nuclear bombs there for four decades, and a crack in the Earth's crust known as the "Gravity Fault" connects its aquifer with Ash Meadows.
It will presumably be another 15,000 years before radioactive water surfaces at Ash Meadows, Nelson said. A more pressing issue for wildlife managers at Ash Meadows is the current decline in populations of Devil's Hole Pupfish and three other endangered fish species.
"Since the crust in Western states is being pulled apart east to west, it creates north-south fault lines such as this one that guides groundwater from one geographically closed basin to another," said Stephen Nelson, a BYU geology professor and co-author of the study.........
Henan Provincial Inst. Cultural Relics and Archaeology Sanyangzhuang tiles set aside to repair a Han house. For hi-res version: news.wustl.edu/news/PublishingImages/tiles.jpeg.
An archeologist at Washington University in St. Louis is helping to reveal for the first time a snapshot of rural life in China during the Han Dynasty.
The rural farming village of Sanyangzhuang was flooded by silt-heavy water from the Yellow River around 2,000 year ago.
Working with Chinese colleagues, T.R. Kidder, PhD, professor and chair of anthropology in Arts & Sciences, is working to excavate the site, which offers a exceptionally well-preserved view of daily life in Western China more than 2,000 years ago.
The research was presented at the Society for American Archeology meeting in St. Louis is April and highlighted last month in Science, the journal of the American Association for the Advancement of Science.
"It's an amazing find," says Kidder of the site, which was discovered in 2003. "We are literally sitting on a gold mine of archeology that is untapped".
What scientists find fascinating and surprising, says Kidder, is that the town, though located in a remote section of the Han Dynasty kingdom, appears quite well off.
Exploration has revealed tiled roofs, compounds with brick foundations, eight-meter deep wells lined with bricks, toilets, cart and human foot tracks, roads and trees.
There is an abundance of metal tools, including plow shares, as well as grinding stones and coins. Also found have been fossilized impressions of mulberry leaves, which scientists see as a sign of silk cultivation.........
This photo from May 21, 2010, shows specimens of 12-million-year old alligator, left, and rhinoceros fossil teeth from the Florida Museum of Natural History collections similar to those used in a new study appearing the Proceedings of the National Academy of Sciences. The study introduces the first method of directly measuring body temperatures of extinct vertebrates using carbon and oxygen isotopes in fossil teeth. The method also could help researchers reconstruct temperatures of ancient environments.
A newly released study by scientists from five institutions including the University of Florida introduces the first method to directly measure body temperatures of extinct vertebrates and help reconstruct temperatures of ancient environments.
The study, appearing in this week's online early edition of Proceedings of the National Academy of Sciences, describes how researchers could use carbon and oxygen isotopes from fossils to more accurately determine whether extinct animals were warm-blooded or cold-blooded and better estimate temperature ranges during the times these animals lived.
"Without a time machine, it has previously been impossible to directly take the temperature of extinct animals such as dinosaurs or megalodon sharks," said co-author of study Richard Hulbert, a vertebrate paleontologist at the Florida Museum of Natural History on the UF campus. "The method described in the study has been shown to work with 12-million-year-old fossils from Florida and the next step is to look at even older fossils. For example, we have no teeth of Titanoboa, the largest snake ever discovered, but we could use 60-million-year-old crocodylian teeth from the same deposit to find out more about the snake's environment".
Funded in part by the National Science Foundation, the new "clumped-isotope" paleothermometer method used in the study analyzes two rare heavy isotopes, carbon-13 and oxygen-18, found in tooth enamel, bones and eggshells.........
Understanding of 2002 break-up of Antarctic ozone hole
Research work on the flow of particles that, in part, relate to pollution dispersion, was conducted by Shane Ross, a Virginia Tech assistant professor of engineering science and mechanics, and featured in Chaos magazine.
Credit: Virginia Tech Photo
The eruption of the volcano in Iceland has drawn attention to air flow patterns, as airlines lost millions of dollars and travelers remained stranded for days to weeks, as particles from the natural disaster traveled over Europe, forcing closures of major airports.
The flow of particles, eventhough seemingly random, can be characterized more effectively, as per work done by Virginia Tech's Shane Ross of the engineering science and mechanics (ESM) department and his colleague Francois Lekien of cole Polytechnique, Universit Libre de Bruxelles, Belgium, who reported their findings in the publication Chaos http://chaos.aip.org/chaoeh/v20/i1.
Their research "will aid researchers and engineers in understanding and in controlling this type of global-scale phenomena, such as pollution dispersion in the atmosphere and the ocean, and large-scale transport of biological organisms, including airborne plant pathogens and respiratory disease agents," said Ishwar Puri, head of the ESM department at Virginia Tech.
For example, the current British Petroleum oil spill in the Gulf of Mexico, might be modeled using Ross and Lekien's findings to provide greater insight into how the particles might be dragged into the Gulf of Mexico's Loop Current.
In explaining how they conducted their research on the flow of particles, Ross and Lekien said they employed existing scientific principles of Lagrangian coherent structures, which reveals the separation of the atmosphere into dynamically distinct regions, to investigate the shapes of geophysical flow patterns. http://www.esm.vt.edu/person.php?id=10139.........
Healthier vegetable oil and tractor fuel to harvest it
Developing fruit of Euonymus alatus, or burning bush. The white seed endosperm produces novel acetyl triacylglycerols, or acTAGs, while the orange aril tissue around the seed produces normal vegetable oil. Photo courtesy of Timothy Durrett, MSU
Genetic discoveries from a shrub called the burning bush, known for its brilliant red fall foliage, could fire new advances in biofuels and low-calorie food oils, as per Michigan State University scientists.
New low-cost DNA sequencing technology applied to seeds of the species Euonymus alatus - a common ornamental planting - was crucial to identifying the gene responsible for its manufacture of a novel, high-quality oil. But despite its name, the burning bush is not a suitable oil crop.
Yet inserted into the mustard weed - well-known to scientists as Arabidopsis and a cousin to commercial oilseed canola - the burning bush gene encodes an enzyme that produces a substantial yield of unusual compounds called acetyl glycerides, or acTAGs. Related vegetable oils are the basis of the world's oilseed industry for the food and biofuels markets, but the oil produced by the burning bush enzyme claims unique and valuable characteristics.
One is its lower viscosity, or thickness.
"The high viscosity of most plant oils prevents their direct use in diesel engines, so the oil must be converted to biodiesel," explained Timothy Durrett, an MSU plant biology research associate. "We demonstrated that acTAGs possess lower viscosity than regular plant oils. The lower viscosity acTAGs could therefore be useful as a direct-use biofuel for a number of diesel engines".........
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