Earth

New research suggests that the Amazon rainforest may be more able to cope with dry conditions than previously predicted. Researchers at the University of Exeter and Colorado State University used a computer model to demonstrate that, providing forest conservation measures are in place, the Amazon rainforest may be more able to withstand periods of drought than has been estimated by other climate models.

In a major new international report, experts conclude that the acidity of the world's ocean may increase by around 170% by the end of the century bringing significant economic losses. People who rely on the ocean's ecosystem services – often in developing countries - are especially vulnerable.

Sediment behind milldams in Pennsylvania preserved leaves deposited just before European contact that provide a glimpse of the ancient forests, according to a team of geoscientists, who note that neither the forests nor the streams were what they are today.

BUFFALO, N.Y. ─ Stingrays swim through water with such ease that researchers from the University at Buffalo and Harvard University are studying how their movements could be used to design more agile and fuel-efficient unmanned underwater vehicles.

The vehicles could allow researchers to more efficiently study the mostly unexplored ocean depths, and they could also serve during clean up or rescue efforts.

In a collaborative effort, researchers in the United States and the United Kingdom have developed a new technique that will help them optimize the transport barrier, or pedestal, in fusion plasmas, which will be key to increasing future fusion power performance. This work has been recognized with the 2013 APS John Dawson Award for Excellence in Plasma Physics Research.

If you want to catch a firefly, any old glass jar will do. But when you're trying to bottle a star—the goal of fusion energy research—the bottle needs to be very special. A tokamak is one type of fusion bottle, capable of holding extremely hot plasma (10 times hotter than the sun) and keeping it stable while harvesting the prodigious amounts of energy produced in the fusion process. Of course, the trick is to keep the hot stuff in. And this is a complicated task.

A team of Chinese and American scientists has learned how to maintain high fusion performance under steady conditions by exploiting a characteristic of the plasma itself: the plasma self-generates much of the electrical current needed for plasma containment in a tokamak fusion reactor. This self-generated, or "bootstrap," current has significant implications for the cost-effectiveness of fusion power.

Although oxygen is required to sustain life, oxygen sucks the life out of fusion by radiating away too much power from the high-temperature plasma. Accordingly, great efforts are expended to reduce the oxygen found in fusion facilities. Surprisingly, recent laboratory experiments and atomistic simulations have found that the oxygen bound by lithium at the walls of fusion devices plays a key role in improving plasma performance.

Recent experiments provide the first assessment of the toughness of a novel lithium coating in the face of intense bombardment by very hot plasma in the divertor region of fusion devices. The results show that this coating can shield the divertor region, which vents plasma exhaust, for 10 times longer than previously expected.

If confirmed by further research, this type of lithium treatment could alleviate widespread concerns that liquid-lithium plasma-facing components will rapidly overwhelm the core of the plasma with impurities and abort fusion reactions.

Materials are widely recognized as one of the critical remaining challenges for making fusion a commercially viable energy source. In a future fusion power plant, the materials surrounding and interacting with the plasma must survive in an extremely hostile environment for up to two years to produce electricity reliably, safely and economically.

Advanced computer codes are helping scientists reimagine how they might initiate a fusion reaction in the center of a tokamak, a doughnut-shaped experimental vessel. These simulations are also shedding new light on complex phenomena in magnetic fields.

Fusion energy requires confining high energy particles, both those produced from fusion reactions and others injected by megawatt beams used to heat the plasma to fusion temperatures.

Experiments at the DIII-D National Fusion Facility in San Diego, California, are shedding light on one of the major mechanisms by which these "fast ions" can be ejected from the plasma. Furthermore, these experiments provide extremely detailed tests of models designed to predict these effects in future reactors.

Sea level rise caused by global warming can prove extremely destructive to island habitats, which hold about 20% of the world's biodiversity. Research by C. Bellard, C. Leclerc and F. Courchamp of the University of Paris Sud look at 3 possible scenarios, from optimistic to very pessimistic, to bring attention to the dangers in store for some of the richest biodiversity hotspots worldwide.

An interdisciplinary team of researchers say they have found 'missing heat' in the climate system, casting doubt on suggestions that global warming has slowed or stopped over the past decade.

Observational data on which climate records are based cover only 84 per cent of the planet – with Polar regions and parts of Africa largely excluded.

New research reveals exactly how the body measures carbon dioxide and suggests that far from being a metabolic waste product, it could play a key role as a biological signalling molecule.