November 19, 2007, 8:36 PM CT

Tsunami-recording in the deep sea

Bremerhaven, November 15, 2007. In order to extend alert times and avoid false alarms, a new seafloor pressure recording system has been designed to detect tsunamis shortly after their development in the open ocean. The project is directed by researchers of the working group Marine Observation Systems at the Alfred Wegener Institute for Polar and Marine Research, part of the Helmholtz Association. Successful testing of the recording system off the Canary Islands in November 2007 means that a new mile stone for the development of the Indian Ocean Tsunami Early Warning System (GITEWS) has been reached.

The GITEWS project is supervised by the German National Research Centre for Geosciences (GFZ) in Postdam. Researchers of the Alfred Wegener Institute, in collaboration with companies Optimare and develogic, and with the Zentrum fr Marine Umweltwissenschaften (MARUM) and the University of Rhode Island, are in the process of developing part of the simulation component and the so-called pressure-based acoustically coupled tsunami detector (PACT) for real-time detection of sea level rises in the deep ocean.

The German tsunami early warning system is unique in that it processes a multitude of information as the basis for a comprehensive and accurate evaluation of every particular situation. Within just few minutes, measurements of the vibrations and horizontal seafloor movements off the coast of Indonesia provide a clear picture of the location and intensity of a seaquake, which, at the warning centre, facilitate the appropriate selection of a previously calculated tsunami propagation model. However, not every seafloor quake causes a tsunami. There is only one way to be clear about this and avoid nerve-wrecking and costly false alarms: we must measure sea level directly, says PACT-project leader Dr Olaf Boebel of the Alfred Wegener Institute......... Posted by: Tyler      Read more         Source

November 19, 2007, 8:20 PM CT

Understanding Smog Formation

Researchers at the U.S. Department of Energy's Brookhaven National Laboratory have developed a new tool for quantitatively measuring elusive atmospheric chemicals that play a key role in the formation of photochemical smog. Better measurements will improve scientists' understanding of the mechanisms of smog formation and their ability to select and predict the effectiveness of various mitigation strategies. The Brookhaven researchers have been issued a U.S. patent for their apparatus, which is available for licensing.

The device measures atmospheric hydroperoxyl radicals - short-lived, highly reactive intermediates involved in the formation of ozone, a component of photochemical smog - in the lowest layer of Earth's atmosphere. The levels of these radicals can indicate which of a variety of chemical pathways is predominant in converting basic starting ingredients - hydrocarbons, nitrogen oxides, and water vapor - into smog in the presence of sunlight.

"Understanding the relative importance of the various pathways can help you tailor your mitigation strategies," said Brookhaven atmospheric chemist Stephen Springston, one of the inventors. "For example, are you better off spending your money reducing hydrocarbon emissions or nitrogen oxide emissions?".

"Our measurements will help predict which strategy would be most successful for a particular set of atmospheric conditions - and make modifications to the strategy as those conditions change," said co-inventor Judy Lloyd of the State University of New York at Old Westbury, who holds a guest appointment at Brookhaven Lab......... Posted by: Tyler      Read more         Source

Tue, 20 Nov 2007 01:35:08 GMT

A Psychic Dog?

Back in 1994 a television company claimed a dog called ''Jaytee'' could psychically sense when its owner returned home. And they had some evidence to back up their claim.

One TV crew was sent out with Jaytee''s owner while she walked around her home town and the other stayed at home with Jaytee. The cameras showed that just as the dog''s owner turned to go home, Jaytee got up and went to the porch and remained there until she returned.

Perhaps this dog really was psychic.

Professor Richard Wiseman, our resident king of weird psychology studies, though, thought there were a number of alternative explanations (Wiseman, Smith & Milton, 1998). Could it be that Jaytee was responding to:

• Routine - has the dog learnt its owner''s routine?
• Can the dog smell its owner at a distance?
• Is the dog picking up cues from those it is with?
• Does the dog just keep guessing, hoping it will get it right once, just like someone performing a ''cold reading''?

There''s only one way to be sure:

Proper experiments
In four experiments carried out in 1995, Wiseman and colleagues set about testing Jaytee''s abilities using the strictest controls:

• Jaytee''s owner''s return was randomly controlled by the random number generator on a Casio calculator.
• No one in the home was aware at what time Jaytee''s owner would return.
• Jaytee''s behaviour was videotaped.
• Jaytee''s owner was not permitted to travel in her own car to avoid the possibility the dog could identify the engine approaching.
• The indication of psychic ability - a trip to the porch - was only considered successful if made within 10 minutes of Jaytee''s owner''s return.
• An independent judge viewed the tape of Jaytee''s behaviour to decide if Jaytee was visiting the porch for some other reason - such as to stare at a passing cat.

Posted by: Jerry      Read more     Source

November 18, 2007, 9:03 PM CT

A New Way To Manipulate Light

Using a special hollow-core photonic crystal fibre, a team at the University of Bath, UK, has opened the door to what could prove to be a new sub-branch of photonics, the science of light guidance and trapping.

The team, led by Dr Fetah Benabid, reports on the discovery, which relates to the emerging attotechnology, the ability to send out pulses of light that last only an attosecond, a billion billionth of a second.

These pulses are so brief that they allow scientists to more accurately measure the movement of sub-atomic particles such as the electron, the tiny negatively-charged entity which moves outside the nucleus of an atom. Attosecond technology may throw light, literally, upon the strange quantum world where such particles have no definite position,only probable locations.

To make attosecond pulses, scientists create a broad spectrum of light from visible wavelengths to x-rays through an inert gas. This normally requires a gigawatt of power, which puts the technique beyond any commercial or industrial use.

But Dr Benabid's team used a photonic crystal fibre (pcf), the width of a human hair, which traps light and the gas together in an efficient way. Until now the spectrum produced by photonic crystal fibre has been too narrow for use in attosecond technology, but the team have now produced a broad spectrum, using what is called a Kagome lattice, using about a millionth of the power used by non-pcf methods......... Posted by: Kevin      Read more         Source

November 15, 2007, 10:32 PM CT

Dinosaur from Sahara ate like a 'mesozoic cow'

110 million-year-old dinosaur that had a mouth that worked like a vacuum cleaner, hundreds of tiny teeth and nearly translucent skull bones will be unveiled Thursday, Nov. 15, at the National Geographic Society.

Found in the Sahara by National Geographic Explorer-in-Residence Paul Sereno, paleontologist and professor at the University of Chicago, the dinosaur is a plant eater known as Nigersaurus taqueti. Originally named by Sereno and his team in 1999 with only a few of its distinctive bones in hand, Nigersaurus has emerged as an anatomically bizarre dinosaur.

Nigersaurus, a younger cousin of the more familiar North American dinosaur Diplodocus, is small for a sauropod, measuring only 30 feet in length. It managed to sustain its elephant-sized body with a featherweight skull armed with hundreds of needle-shaped teeth, said Sereno. Barely able to lift its head above its back, Nigersaurus operated more like a Mesozoic cow than a reptilian giraffe, mowing down mouthfuls of greenery that consisted largely of ferns and horsetails.

Details of the dinosaurs anatomy and lifestyle will be published Nov. 21, 2007, (available Nov. 15) in PLoS ONE, the online journal from the Public Library of Science, as well as in a cover article in the December 2007 issue of National Geographic magazine, Extreme Dinosaurs......... Posted by: William      Read more         Source

November 15, 2007, 10:07 PM CT

Earth's crust reveals inner workings of a tsunami factory

AUSTIN, TexasResearch announced this week by a team of U.S. and Japanese georesearchers may help explain why part of the seafloor near the southwest coast of Japan is especially good at generating devastating tsunamis, such as the 1944 Tonankai event, which killed at least 1,200 people. The findings will help researchers assess the risk of giant tsunamis in other regions of the world.

Georesearchers from The University of Texas at Austin and his colleagues used a commercial ship to collect three-dimensional seismic data that reveals the structure of Earths crust below a region of the Pacific seafloor known as the Nankai Trough. The resulting images are akin to ultrasounds of the human body.

The results, published this week in the journal Science, address a long standing mystery as to why earthquakes below some parts of the seafloor trigger large tsunamis while earthquakes in other regions do not.

The 3D seismic images allowed the scientists to reconstruct how layers of rock and sediment have cracked and shifted over time. They found two things that contribute to big tsunamis. First, they confirmed the existence of a major fault that runs from a region known to unleash earthquakes about 10 kilometers (6 miles) deep right up to the seafloor. When an earthquake happens, the fault allows it to reach up and move the seafloor up or down, carrying a column of water with it and setting up a series of tsunami waves that spread outward......... Posted by: Tyler      Read more         Source

November 14, 2007, 9:41 PM CT

Pushing transmission rate of copper cables

You may not be able to get blood out of a turnip, but as per Penn State engineers, you can increase the data transmission of Category-7 copper cables used to connect computers to each other and the Internet.

"Working with NEXANS, the company that manufactures the cable, we have examined the possibility of sending digital data at a rate of 100 gigabits per second over 100 meters of Category-7 copper cable," says Mohsen Kavehrad, the W.L. Weiss Endowed Chair professor of electrical engineering. "These are the current, new generation of Ethernet cables".

These cables are used to connect computers within a room or a building or to create parallel computing systems.

While the long distance lines of most Internet systems are glass fiber optic cables, which are very fast, copper cable is generally used for short distances.

"In home networks, for example, it is expensive to use fiber optic cabling," says Ali Enteshari, graduate student in electrical engineering who presented the team's methods to the IEEE High Speed Study Group today (Nov. 14) in Atlanta.

All transmission cables are limited by the distance they can transmit data without degradation of the signal. Before errors and interference make the signals non-recoverable, cable systems use repeaters which are similar to computer modems to capture, correct or recover data, and resend it. The distance between repeaters depends on the cable and the approach used by the modem to correct errors......... Posted by: Kevin      Read more         Source

November 14, 2007, 8:50 PM CT

Fire, ice, and invasion

Special Issue of Frontiers in Ecology and the Environment focuses on paleoecology, which uses fossilized remains and soil and sediment cores to reconstruct past ecosystems.

Some researchers argue that the pre-Columbian Amazon was pristine, with indigenous people living in harmony with nature. Others suggest that the Amazon is a manufactured landscape, altered by and disturbed by human activities even before the arrival of Europeans. In Amazonian exploitation revisited: ecological asymmetry and the policy pendulum, Mark Bush (Florida Institute of Technology) and Miles Silman (Wake Forest University) discuss this debate.

Bush and Silman present paleodata from fossil pollen and charcoal in soil cores that support both perspectives. They argue that in some areas of the Amazon, human impact was extreme, particularly on bluffs around rivers. Yet they also found vast stretches of the forest where human influence was minimal. If widespread disturbance was typical in the Amazon forest until just 500 years ago, that suggests the ecosystem is resilient to human activities, including logging. However, as the authors demonstrate, the manufactured landscape argument only holds true for localized patches of forest, and should not be used as a basis for management of the Amazon as a whole......... Posted by: William      Read more         Source

November 13, 2007, 9:35 PM CT

Ice age imprint found on cod DNA

An international team of researchers, led by the University of Sheffield, has demonstrated how Atlantic cod responded to past natural climate extremes. The new research could help in determining cods vulnerability to future global warming.

With fishing pressures high and stock size low, there is already major concern over the current sustainability of cod and other fisheries. The new findings, reported in the journal, Proceedings of the Royal Society B, show that natural climate change has previously reduced the range of cod to around a fifth of what it is today, but despite this, cod continued to populate both sides of the North Atlantic.

The scientists used a computer model and DNA techniques to estimate where cod could be found in the ice age, when colder temperatures and lower sea-levels caused the extinction of some populations and the isolation of others.

The computer models used to estimate ice-age habitats suitable for cod were developed by Professor Grant Bigg, Head of the University of Sheffields Department of Geography. These climatic analyses were combined with genetic studies by US scientists at Duke University and the University of California, and ecological information prepared by colleagues at the University of East Anglia and the Institute of Marine Research in Norway......... Posted by: William      Read more         Source

November 13, 2007, 9:28 PM CT

Regional variation in warming from sun

A NASA satellite designed, built and controlled by the University of Colorado at Boulder is expected to help researchers resolve wide-ranging predictions about the coming solar cycle peak in 2012 and its influence on Earth's warming climate, as per the chief scientist on the project.

Senior Research Associate Tom Woods of CU-Boulder's Laboratory for Atmospheric and Space Physics said the brightening of the sun as it approaches its next solar cycle maximum will have regional climatic impacts on Earth. While some researchers predict the next solar cycle -- expected to start in 2008 -- will be significantly weaker than the present one, others are forecasting an increase of up to 40 percent in the sun's activity, said Woods.

Woods is the principal investigator on NASA's $88 million Solar Radiation and Climate Experiment, or SORCE, mission, launched in 2003 to study how and why variations in the sun affect Earth's atmosphere and climate. In August, NASA extended the SORCE mission through 2012. The extension provides roughly $18 million to LASP, which controls SORCE from campus by uploading commands and downloading data three times daily to the Space Technology Building in the CU Research Park.

Solar cycles, which span an average of 11 years, are driven by the amount and size of sunspots present on the sun's surface, which modulate brightness from the X-ray to infrared portion of the electromagnetic spectrum. The current solar cycle peaked in 2002......... Posted by: Tyler      Read more         Source