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A watery surprise from Earth's depths: Mineral provides first direct evidence for water in mantle's transition zone

From a depth of more than 500 kilometers, Earth has coughed up a water-bearing mantle mineral never before found on the surface. The surprise finding suggests the planet’s interior holds more water than all its oceans combined, and could help explain how Earth’s massive tectonic plates move.

14 Jul 2014

Ancient food web shows modern structure

All animals have to eat, but who eats whom or what is often difficult for ecologists to discern in modern habitats, let alone in extinct ecosystems. Now a new study focusing on an exceptional assemblage of 48-million-year-old fossils in Germany has pieced together one of the most complex food webs ever constructed, and the results show this ancient ecosystem was strikingly similar to today’s food webs.

11 Jul 2014

Solar wind gives lightning a boost

Strong gusts of solar wind appear to trigger lightning on Earth, according to a new study. Researchers studying patterns of lightning strikes in and around the U.K. over several years found a substantial uptick in lightning after high-speed streams of solar wind reached Earth. Given the regular timing of the streams’ arrivals and our ability to detect them with satellites, the findings could eventually help scientists better forecast lightning activity, potentially mitigating the hazard it poses to humans.

10 Jul 2014

Mars Monthly

As Curiosity and Opportunity rove around Mars, the Mars Reconnaissance Orbiter (MRO), Mars Express and Mars Odyssey orbit above, and scientists on Earth study the Red Planet from afar, new findings are announced almost weekly. Here are a few of the latest updates.
 

10 Jul 2014

Searching for evidence of ancient subduction

For billions of years, portions of Earth’s rigid surface have dipped and sunk along plate boundaries to be recycled back into the mantle below. Determining when the process of subduction began — a fundamental step in Earth’s physical, and possibly biological, evolution — has proved difficult for geoscientists due to the challenges of interpreting evidence from the few remnants of early Earth that remain. In a recent study, researchers have now proposed a new approach for identifying ancient subduction zones that could help tackle the longstanding question.
 

06 Jul 2014

Mercury's shrinkage underestimated

In addition to its myriad craters, Mercury is marked by mountainous ridges and faults that, similar to wrinkles that emerge on an overripe apple as it shrinks, are signs that Mercury’s surface has cracked and buckled as the planet has cooled. From previous observations, it was estimated that Mercury’s radius had decreased 1 to 3 kilometers in about the past 4 billion years, but according to a new study in Nature Geoscience, the amount of contraction has been greatly underestimated.
 

06 Jul 2014

Message in a bottle gourd

For about the last 10,000 years, bottle gourds (Lagenaria siceraria) have been cultivated the world over for food and crafted into canteens, instruments and other utilitarian goods. But just how they became globally ubiquitous by the Early Holocene has long been a subject of debate among anthropologists and archaeologists. Some scientists thought the plant migrated with humans from Africa to Asia and, eventually, across the Bering land bridge to the Americas. But a new study suggests it’s unlikely the plants would have survived the long trek through harsh Arctic conditions, and instead offers a different globe-tripping hypothesis for everyone’s favorite dried fruit-turned-drinking vessel.

04 Jul 2014

Belugas, climate, mercury and cancer

Overall, the beluga whale population in the Arctic is robust and healthy, reported Stephen Raverty, a veterinary pathologist with the British Columbia Ministry of Agriculture and the University of British Columbia who has long studied belugas, at the AAAS meeting.

03 Jul 2014

Parasites spread across the Arctic under the 'new normal'

The last several decades have seen Arctic sea-ice minimums drop by more than half in sea-ice area and more than three-quarters in volume. With current models expecting further reductions, scientists are calling it the “new normal” and are trying to grasp its implications — one of which is the occurrence of pathogens never before seen in the Arctic.

02 Jul 2014

Shifting winds blow away Taupo's 'Ultraplinian' title

The eruption of New Zealand’s Taupo volcano about 1,800 years ago is the stuff of legends. With an ash plume estimated to have reached an astounding height of 50 kilometers — substantially higher than any other known eruption — Taupo was once thought to justify its own volcanic explosivity category: Ultraplinian. But new research looking at the effects of changing wind patterns on the eruptive deposits left by Taupo may lead scientists to downgrade the event to Plinian, effectively making the term Ultraplinian obsolete.
 

01 Jul 2014

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