Earth

WASHINGTON— Even before the dawn of agriculture, people may have caused the planet to warm up, a new 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 new study, accepted for publication in Geophysical Research Letters, argues that this die-off had the side effect of heating up the planet.

Dartmouth researchers contribute to solving a quantum puzzle

HANOVER, NH – Dartmouth researchers have discovered a potentially important piece of the quantum/classical puzzle – learning how the rules of physics in the quantum world (think smaller than microscopic) change when applied to the classical world (think every day items, like cars and trees).

Unpeeling atoms and molecules from the inside out

Menlo Park, Calif.--The first published scientific results from the world's most powerful hard X-ray laser, located at the Department of Energy's SLAC National Accelerator Laboratory, show its unique ability to control the behaviors of individual electrons within simple atoms and molecules by stripping them away, one by one—in some cases creating hollow atoms.

Switching off lights, turning the television off at the mains and using cooler washing cycles could have a much bigger impact on reducing carbon dioxide emissions from power stations than previously thought, according to a new study published this month in the journal Energy Policy. The study shows that the figure used by government advisors to estimate the amount of carbon dioxide saved by reducing people's electricity consumption is up to 60 percent too low.

College Park, MD (June 29, 2010) -- Since Richard Feynman's first envisioned the quantum computer in 1982, there have been many studies of potential candidates -- computers that use quantum bits, or qubits, capable of holding an more than one value at a time and computing at speeds far beyond existing silicon-based machines for certain problems. Most of these candidate systems, such as atoms and semiconducting quantum dots, work for quantum computing, but only at very low temperatures.

College Park, MD (June 22, 2010) -- Integrated circuits, which enable virtually every electronics gadget you use on a daily basis, are constantly being pushed by the semiconductor industry to become smaller, faster, and cheaper. As has happened many times in the past and will continue in the future, integrated circuit scaling is perpetually in danger of hitting a wall that must be maneuvered around.

College Park, MD (June 29, 2010) -- Wind turbines may be one of the best renewable energy solutions, but as turbines get larger they also get noisier, become more of an eyesore, and require increasingly larger expanses of land. One solution: ocean-based wind turbines. While offshore turbines already have been constructed, they've traditionally been situated in shallow waters, where the tower extends directly into the seabed.

The northern Gulf of Mexico hypoxic zone, an underwater area with little or no oxygen known commonly as the "dead zone," could be larger than the recent average, according to a forecast by a team of NOAA-supported scientists from the Louisiana Universities Marine Consortium, Louisiana State University, and the University of Michigan.

Palo Alto, CA— One proposed emergency fix to halt global warming is to seed clouds over the ocean to make them more reflective, reducing the solar radiation absorbed by the Earth. But the scheme could also change global rainfall patterns, raising concerns of water shortages on land. A new study by the Carnegie Institution, in collaboration with the Indian Institute of Science, suggests that altered atmospheric circulation under the scheme in fact could increase monsoonal rains and cause the continents to become wetter, not drier, on average.

Why mercury is more dangerous in oceans

DURHAM, N.C. -- Even though freshwater concentrations of mercury are far greater than those found in seawater, it's the saltwater fish like tuna, mackerel and shark that end up posing a more serious health threat to humans who eat them.

The answer, according to Duke University researchers, is in the seawater itself.

GAINESVILLE, Fla. --- When high-temperature superconductors were first announced in the late 1980s, it was thought that they would lead to ultra-efficient magnetic trains and other paradigm-shifting technologies.

That didn't happen. Now, a University of Florida scientist is among a team of physicists to help explain why.