December 4, 2007, 10:20 PM CT

Research On Hydrogen Storage

Research on hydrogen-fueled cars may be one step closer to application thanks to a new form of hydride discovered by researchers at the ESRF. The material, lithium borohydride, is a promising energy storage system: it contains 18 weight percents of hydrogen, which makes it attractive for use in hydrogen-fueled cars. Its drawback is that it only releases hydrogen at quite high temperatures (above 300 degrees C). The team at the ESRF has found a new form of the compound that could possibly release hydrogen in mild conditions. This discovery, completely unexpected from the point of view of theoretical predictions, is published recently as a Very Important Paper in Angewandte Chemie.

Atomative industry hydrogen as a perspective energy carrier. If a good hydrogen strorage material will be developed, the petrol in cars can be replaced by clean hydrogen energy. Five kilograms of hydrogen would take you as far as twenty liters of petrol. Today there are several compounds of interest, which are known to either store relatively large amounts of hydrogen or release it easily, but none do both in a way suitable for practical application.

Scientists at the Swiss-Norwegian experimental stations (beamlines) at the ESRF are currently studying several compounds of light elements with hydrogen and the different forms they take at different pressure and temperature. Lithium borohydride, LiBH4, is one of the compounds they study as it has a high weight content of hydrogen (18%). The new form of this compound, which researchers have just discovered, is promising because it appears to be unstable. Until......... Posted by: Sarah      Read more         Source

December 4, 2007, 10:08 PM CT

Increased Chances For Stormy Weather

Scientists who study severe weather and climate change joined forces to study the effects of global warming on the number of severe storms in the future and discovered a dramatic increase in potential storm conditions for some parts of the United States.

The Purdue University-led team used climate models to examine future weather conditions favorable to formation of severe thunderstorms - those that produce flooding, damaging winds, hail and sometimes spawn tornadoes.

"It seems that areas in the U.S. prone to severe thunderstorms now will likely have more of them in the future," said Robert Trapp, the Purdue associate professor of earth and atmospheric sciences who led the research team. "We can't predict individual storms, but we can project the number of days with conditions conducive to storm formation".

The study observed that by the end of this century the number of days that favor severe storms could more than double in locations such as Atlanta and New York. The study also observed that the increase in storm conditions occurs during the typical storm seasons for these locations and not during dry seasons when such storms could be beneficial. The findings will be published online this week in the Proceedings of the National Academy of Sciences......... Posted by: Tyler      Read more         Source

December 3, 2007, 10:15 PM CT

Toll of climate change on world food supply

Global agriculture, already predicted to be stressed by climate change in coming decades, could go into steep, unanticipated declines in some regions due to complications that researchers have so far inadequately considered, say three new scientific reports. The authors say that progressive changes predicted to stem from 1- to 5-degree C temperature rises in coming decades fail to account for seasonal extremes of heat, drought or rain, multiplier effects of spreading diseases or weeds, and other ecological upsets. All are believed more likely in the future. Coauthored by leading scientists from Europe, North America and Australia, they appear in this weeks issue of the Proceedings of the National Academy of Sciences (PNAS).

A number of people assume that we will never have a problem with food production on a global scale. But there is a strong potential for negative surprises, said Francesco Tubiello, a physicist and agricultural expert at the NASA/Goddard Institute of Space Studies who coauthored all three papers. Goddard is a member of Columbia Universitys Earth Institute.

In order to keep pace with population growth, current production of grainfrom which humans derive two-thirds of their proteinwill probably have to double, to 4 billion tons a years before 2100. Studies in the past 10 years suggest that mounting levels of carbon dioxide in the airthought to bethe basis of human-caused climate changemay initially bolster the photosynthetic rate of a number of plants, and, along with new farming techniques, possibly add to some crop yields. Between now and mid-century, higher temperatures in northerly latitudes will probably also expand lands available for farming, and bring longer growing seasons. However, these gains likely will be canceled by agricultural declines in the tropics, where even modest 1- to 2-degree rises are expected to evaporate rainfall and push staple crops over their survival thresholds. Existing research estimates that developing countries may lose 135 million hectares (334 million acres) of prime farm land in the next 50 years. After mid-century, continuing temperature rises5 degrees C or more by then--are expected to start adversely affecting northern crops as well, tipping the whole world into a danger zone......... Posted by: Tyler      Read more         Source

December 2, 2007, 9:22 PM CT

The best sources of geothermal energy

With fossil fuel sources depleting and global warming on the rise, exploring alternative means of power for humans is a necessary reality. Now, looking to the sky, relying on the wind or harnessing water power are not the only remaining options. Deep within Earth is an untapped source of energy: geothermal energy.

It has been estimated that within the continental United States, there is a sizable resource of accessible geothermal energy about 3,000 times the current annual U.S. consumption.

Two important reasons this storehouse of energy has not been tapped is that locating the specific energy hot spots is difficult and expensive.

Since a number of geothermal resources are hidden, that is, they do not show any clear indications of their presence at the surface, locating them by just using observations made at the surface is difficult, explains Matthijs van Soest, associate research professional at the Noble Gas Geochemistry and Geochronology Laboratory within the School of Earth and Space Exploration at Arizona State University.

Often when people thought there might be a geothermal resource below the surface the only way to determine if their assumption was correct was drilling and drilling is extremely expensive, he says.

Now, research by van Soest and B. Mack Kennedy at Lawrence Berkeley National Laboratory reveals that geothermal exploration doesnt have to be high-priced......... Posted by: Sarah      Read more         Source

December 2, 2007, 9:12 PM CT

Between water and rock

Water chemistry and mineralogy are scientific fields that have been around long enough to develop extensive knowledge and technologies. The boundary of water and rock, however, is not a thin wet line but the huge new field of nanoparticle science.

Researchers are discovering that aquatic nanoparticles, from 1 to 100 nanometers, influence natural and engineered water chemistry and systems differently than similar materials of a larger size. Nanoparticles are in an awkward intermediate state, between elements dissolved in water and minerals that you can hold in your hand, said Michael Hochella Jr., University Distinguished Professor of geosciences at Virginia Tech. The nanoscale represents a transition zone. For instance, the electronic, magnetic, and optical properties at the atomic, nano, and bulk scales are all different.

The cover story of the recent issue of the Royal Society of Chemistrys Journal of Environmental Monitoring (www.rsc.org/Publishing/Journals/em/) offers a critical review of the emerging field of Aquatic environmental nanoparticles. Written by Virginia Tech Ph.D. students Nicholas S. Wigginton of Holt, Mich., and Kelly (Plathe) Haus of Rochester, Minn., and Hochella, the article looks at recent advances in identifying nanoparticles in water and in understanding their properties and reactivity......... Posted by: Sarah      Read more         Source

November 29, 2007, 10:53 PM CT

Youngest solar systems detected

ANN ARBOR, Mich.---Astronomers at the University of Michigan have found what are thought to besome of the youngest solar systems yet detected.

The systems are around the young stars UX Tau A and LkCa 15, located in the Taurus star formation region just 450 light years away. Using a telescope that measures levels of infrared radiation, the scientists noticed gaps in the protoplanetary disks of gas and dust surrounding these stars. They say those gaps are most likely caused by infant planets sweeping those areas clear of debris.

A paper on the findings by astronomy doctoral student Catherine Espaillat, professor Nuria Calvet, and their colleagues is reported in the Dec. 1 issue of Astrophysical Journal Letters.

"Previously, astronomers were seeing holes at the centers of protoplanetary disks and one of the theories was that the star could be photoevaporating that material," said Espaillat, first author of the paper.

Photoevaporation refers to the process of heating up the dust and gas in the surrounding cloud until it evaporates and dissipates.

"We observed that in some stars, including these two, instead of a hole, there's a gap," Espaillat said. "It's more like a lane has been cleared within the disk. That is not consistent with photoevaporation. The existence of planets is the most probable theory that can explain this structure"......... Posted by: Brooke      Read more         Source

November 29, 2007, 10:50 PM CT

Having the climate cake and eating it, too

Is it possible to solve climate change, reduce poverty and save biodiversity at a single stroke" It might seem like a dream, but this is exactly the issue that is being discussed at the United Nations Climate Change Conference (UNFCCC) in Bali 3-14 December 2007. The key is to include reduced emissions from deforestation and degradation (REDD) in the Kyoto Protocol so that developing countries can be compensated for saving their forests and woodlands.

A recent paper in the African Journal of Ecology points out that the Intergovernmental Panel on Climate Change (IPCC) estimates that 20-25% of current annual carbon emissions result from loss of tropical forest. This has prompted efforts to renegotiate climate change policy to include REDD so that tropical forest nations can claim compensation for sustainable management of their natural forest resources. But not all tropical countries are pushing for an agreement and a number of African countries do not appear to be participating in the discussion. Eliakimu Zahabu from the Sokoine University of Agriculture in Tanzania and lead author on the paper suggests that The lack of African action might be partly because estimation of carbon emission from the forest sector has been based on forest areas cleared entirely, i.e. deforestation, but excludes the small-scale degradation processes common in African dry forests. This means that the concepts for lowering carbon emissions from developing countries that have been worked out under the climate change agreements need rethinking. Dr Margaret Skutsch, from the University of Twente in the Netherlands, has been studying the problem for five years Degradation is often a different process with different drivers and needs a different instrument in Kyoto she says, and adds for African countries to benefit from the new policy, they need to support the idea of reduced emissions from controlling degradation in a way that reflects African realities, and to do this they need to engage in the debate......... Posted by: Tyler      Read more         Source

November 29, 2007, 10:46 PM CT

New research discredits $100B global warming 'fix'

Researchers have revealed an important discovery that raises doubts concerning the viability of plans to fertilize the ocean to solve global warming, a projected $100 billion venture.

Research performed at Stanford and Oregon State Universities, reported in the Journal of Geophysical Research, suggests that ocean fertilization may not be an effective method of reducing carbon dioxide in the atmosphere, a major contributor to global warming. Ocean fertilization, the process of adding iron or other nutrients to the ocean to cause large algal blooms, has been proposed as a possible solution to global warming because the growing algae absorb carbon dioxide as they grow.

However, this process, which is analogous to adding fertilizer to a lawn to help the grass grow, only reduces carbon dioxide in the atmosphere if the carbon incorporated into the algae sinks to deeper waters. This process, which researchers call the Biological Pump, has been believed to be dependent on the abundance of algae in the top layers of the ocean. The more algae in a bloom, the more carbon is transported, or pumped, from the atmosphere to the deep ocean.

To test this theory, scientists compared the abundance of algae in the surface waters of the worlds oceans with the amount of carbon actually sinking to deep water. They found clear seasonal patterns in both algal abundance and carbon sinking rates. However, the relationship between the two was surprising: less carbon was transported to deep water during a summertime bloom than during the rest of the year. This analysis has never been done before and mandatory designing specialized mathematical algorithms......... Posted by: Tyler      Read more         Source

November 29, 2007, 9:10 PM CT

Helium Isotopes Point to New Sources of Geothermal Energy

Currently, most developed geothermal energy comes from regions of volcanic activity, such as The Geysers in Northern California. The potential resources identified by Kennedy and van Soest arise not from volcanism but from the flow of surface fluids through deep fractures that penetrate the earth's lower crust, in regions far from current or recent volcanic activity. The scientists report their findings in the November 30, 2007 issue of Science.

"A good geothermal energy source has three basic requirements: a high thermal gradient - which means accessible hot rock - plus a rechargeable reservoir fluid, commonly water, and finally, deep permeable pathways for the fluid to circulate through the hot rock," says Kennedy, a staff scientist in Berkeley Lab's Earth Sciences Division. "We believe we have found a way to map and quantify zones of permeability deep in the lower crust that result not from volcanic activity but from tectonic activity, the movement of pieces of the Earth's crust."

Kennedy and van Soest made their discovery by comparing the ratios of helium isotopes in samples gathered from wells, surface springs, and vents across the northern Basin and Range. Helium-three, whose nucleus has just one neutron, is made only in stars, and Earth's mantle retains a high proportion of primordial helium-three (in comparison to the minuscule amount found in air) left over from the formation of the solar system. Earth's crust, conversely, is rich in radioactive elements like uranium and thorium that decay by emitting alpha particles, which are helium-four nuclei. Thus a high ratio of helium-three to helium-four in a fluid sample indicates that much of the fluid came from the mantle......... Posted by: Sarah      Read more         Source

November 29, 2007, 4:22 PM CT

The ingredients for more powerful Atlantic hurricanes

As the world warms, the interaction between the Atlantic Ocean and atmosphere may be the recipe for stronger, more frequent hurricanes.

University of Wisconsin-Madison researchers have observed that the Atlantic organizes the ingredients for a powerful hurricane season to create a situation where either everything is conducive to hurricane activity or nothing is-potentially making the Atlantic more vulnerable to climate change than the world's other hurricane hot spots.

After the 2004 and 2005 hurricane seasons, a number of worry what Atlantic hurricane seasons will look like in a warmer world. Evidence indicates that higher ocean temperatures add a lot of fuel to these devastating storms. In a paper published recently in the "Bulletin of the American Meteorological Society," co-authors Jim Kossin and Dan Vimont caution against only looking at one piece of the puzzle. "Sea surface temperature is a bit overrated," says Kossin, an atmospheric scientist at UW-Madison's Cooperative Institute of Meteorological Satellite Studies. "It's part of a larger pattern".

Kossin and Vimont, a professor in the Department of Atmospheric and Oceanic Sciences, noticed that warmer water is just one part of a larger pattern indicating that the conditions are right for more frequent, stronger hurricanes in the Atlantic. The atmosphere reacts to ocean conditions and the ocean reacts to the atmospheric situation, creating a distinct circulation pattern known as the Atlantic Meridional Mode (AMM). The AMM unifies the connections among the factors that influence hurricanes such as ocean temperature, characteristics of the wind, and moisture in the atmosphere......... Posted by: Tyler      Read more         Source