Earth | Page 672 | Science Codex

Physics for the mechanism of slow change in microscopic magnetic structures revealed

The research group of Professor Hideo Ohno and Associate Professor Shunsuke Fukami of Tohoku University has studied in detail, a slow change of microscopic magnetic structures in metallic wires induced by external driving forces, commonly called "creep" motion. This has allowed them to clarify the physics of how the driving forces, magnetic fields or electric currents, act on the magnetic structure.

Previous studies had shown that while the actions of magnetic fields and currents are the same for metallic materials, they are fundamentally different for semiconductor materials.

West Coast marine mammals respond to shifting conditions, new research shows

Humpback whales off the West Coast consume thousands of pounds of krill, plankton and small fish each day. Research shows that humpback diets reflect their surroundings, with the truck-sized whales filter-feeding on vast amounts of krill when cold upwelling waters prevail, but switching to schooling fish such as anchovies when warmer waters take over and the fish grow abundant.

USF geologists focus on mineral for clues to beginning of biological life on earth

On the early Earth, light came not only from the sun but also from the incessant bombardment of fireball meteorites continually striking the planet. Now, the recent work of University of South Florida (USF) associate professor of geology Matthew Pasek, USF researcher Maheen Gull, and colleagues at Georgia Institute of Technology, has demonstrated that these meteorites may have carried within them an extraterrestrial mineral that, as it corroded in water on Earth, could have provided the essential chemical spark leading to the birth of biological life on the planet.

Hot water puts crocs at risk

Australia's saltwater crocodiles appear to be in hot water, with a University of Queensland study linking climate warming to shorter dives, putting the crocs' survival at risk.

Professor Craig Franklin of the UQ School of Biological Sciences said saltwater crocodiles exposed to long-term elevated water temperature spent less time submerged once water temperature exceeded 31.5 degrees Celsius.

"We thought that crocodiles - like many animals - would adjust to temperature changes so life continues," he said.

'Freak' ocean waves hit without warning, new research shows

Mariners have long spoken of 'walls of water' appearing from nowhere in the open seas. But oceanographers have generally disregarded such stories and suggested that rogue waves - enormous surface waves that have attained a near-mythical status over the centuries - build up gradually and have relatively narrow crests.

Predators key to helping prey evolve with climate change

The key to helping animals evolve quickly in response to climate change could actually be their predators, according to a new UBC study.

North Slope permafrost thawing sooner than expected

New projections of permafrost change in northern Alaska suggest far-reaching effects will come sooner than expected, scientists reported this week at the fall meeting of the American Geophysical Union.

"The temperature of permafrost is rapidly changing," said Vladimir Romanovsky, head of the Permafrost Laboratory at the University of Alaska Fairbanks Geophysical Institute.

Greenhouse gas emissions from freshwater higher than thought

MADISON, Wis. - Do not underestimate the babbling brook. When it comes to greenhouse gases, these bucolic water bodies have the potential to create a lot of hot air.

According to a new analysis in the journal Ecological Monographs, by researchers at the University of Wisconsin-Madison and colleagues, the world's rivers and streams pump about 10 times more methane into our atmosphere than scientists estimated in previous studies. The new study also found that human activity seems to drive which streams are the biggest contributors.

New results from LUX

The Large Underground Xenon (LUX) dark matter experiment has already proved itself to be the most sensitive dark matter detector in the world. Now, a new set of calibration techniques employed by LUX scientists has once again dramatically improved its sensitivity.

Researchers with LUX, which operates nearly a mile underground in a former gold mine the Black Hills of South Dakota, are looking for WIMPs. These weakly interacting massive particles are among the leading candidates for dark matter.

East Antarctic Ice Sheet has stayed frozen for 14 million years, Penn team reports

Antarctica was once a balmier place, lush with plants and lakes. Figuring out just how long the continent has been a barren, cold desert of ice can give clues as to how Antarctica responded to the effects of past climates and can perhaps also indicate what to expect there in the future as Earth's atmospheric concentration of carbon dioxide grows.

NASA examines global impacts of the 2015 El Nino

People the world over are feeling, or soon will feel, the effects of the strongest El Niño event since 1997-98, currently unfolding in the eastern equatorial Pacific Ocean. New satellite observations are beginning to show scientists its impact on the distribution of rain, tropospheric ozone and wildfires around the globe.

Study: Current climate models misrepresent El Niño

An analysis of fossil corals and mollusk shells from the Pacific Ocean reveals there is no link between the strength of seasonal differences and El Niño, a complex but irregular climate pattern with large impacts on weather, agriculture, fisheries, tourism, and air quality worldwide.

The finding contradicts the top nine climate models in use today, which associate exceptionally hot summers and cold winters with weak El Niños, and vice versa.

Warmer air and sea, declining ice continue to trigger Arctic change

A new NOAA-sponsored report shows that air temperature in 2015 across the Arctic was well above average with temperature anomalies over land more than 2 degrees Fahrenheit above average, the highest since records began in 1900. Increasing air and sea surface temperatures, decreasing sea ice extent and Greenland ice sheet mass, and changing behavior of fish and walrus are among key observations released today in the Arctic Report Card 2015.

New NASA satellite maps show human fingerprint on global air quality

Using new, high-resolution global satellite maps of air quality indicators, NASA scientists tracked air pollution trends over the last decade in various regions and 195 cities around the globe. The findings were presented Monday at the American Geophysical Union meeting in San Francisco and published in the Journal of Geophysical Research.

Age of blueschist is not an indicator of the date of emergence of plate tectonics

One of the big mysteries in the history of the Earth is the emergence of plate tectonics. When exactly did the processes of plate tectonics begin that today involve the subduction of oceanic plates? Scientific opinion varies widely as to this. The dominant view is that oceanic plates have been pushing under other plates and sinking into the Earth's mantle - a process known as subduction - since the beginning of the Hadean eon, more than four billion years ago. Others date the onset of plate tectonic movements to the Neoproterozoic era of 500 to 1,000 million years ago.