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Draining Greenland lakes unlikely to contribute to sea-level rise

Each summer, Greenland’s ice sheet — the world’s second-largest expanse of ice, measuring three times the size of Texas — begins to melt. Pockets of melting ice form hundreds of large, “supraglacial” lakes on the surface of the ice. Many of these lakes drain through cracks and crevasses in the ice sheet, creating a liquid layer over which massive chunks of ice can slide. This natural conveyor belt can speed ice toward the coast, where it eventually falls off into the sea. In recent years, scientists have observed more lakes forming toward the center of the ice sheet — a region that had been previously too cold to melt enough ice for lakes to form.

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Could genetically modified mosquitos prevent mosquito-borne illnesses?

When people think of genetically modified organisms, food crops like GM corn and soybeans usually come to mind. But engineering more complex living things is now possible, and the controversy surrounding genetic modification has now spread to the lowly mosquito, which is being genetically engineered to control mosquito-borne illnesses.

A U.K.-based company, Oxitec, has altered two genes in the Aedes aegypti mosquito so that when modified males breed with wild females, the offspring inherit a lethal gene and die in the larval stage. The state agency that controls mosquitos in the Florida Keys is awaiting approval from the federal government of a trial release of Oxitec’s genetically modified mosquitos to prevent a recurrence of a dengue fever outbreak. But some people in the Keys and elsewhere are up in arms, with more than 155,000 signing a petition opposing the trial of genetically engineered mosquitoes in a small area of 400 households next to Key West. 

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El Niños and Bunny Booms

At times during the past 10,000 years, cottontails and hares reproduced like rabbits and their numbers surged when the El Niño weather pattern drenched the Pacific Coast with rain, according to a University of Utah analysis of 3,463 bunny bones. The study of ancient rabbit populations at a Baja California site may help scientists better understand how mammals that range from the coast to the interior will respond to climate change, says anthropology doctoral student Isaac Hart. He is first author of the study to be published in the July issue of the journal Quaternary Research.

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Massive development possible near Grand Canyon National Park

More than 200,000 people flooded the U.S. Forest Service with comments over the last month calling for the agency to reject a plan for roads and infrastructure that would enable construction of a mega-development on the Grand Canyon’s doorstep. 

The proposed roads, sewers and other utilities would pave the way for a multinational developer to transform the 580-resident community of Tusayan, Ariz., from a small, quiet tourist town into a sprawling complex of high-end homes, retail stores and restaurants only a mile from the Grand Canyon National Park boundary. The development threatens groundwater that feeds the Grand Canyon’s creeks, springs and seeps, endangering some of the park’s most important and biodiverse wildlife habitat. 

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EU considering new limitations on diesel engines in non-road machinery

As air pollution spikes in Europe’s cities prompt car-free days and talk of banning diesel cars, it’s easy to forget the other culprits behind the air quality crisis: diesel machines. Known in legislation by the innocuous term ‘non-road mobile machinery’, their air pollutant emission limits are now finally under revision.

The last directive dated back to 1997 and the new rules will set standards for decades to come. Air pollution is causing more than 450,000 premature deaths every year in Europe and a recent Eurobarometer survey confirmed that air pollution is now the biggest environmental concern of European citizens. Efficient regulation of emissions sources is therefore key to mitigating the exposure of citizens to air pollution.

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The Dangers of Microbeads in Personal Care Products

Microbeads, those tiny plastic beads included in personal care products for exfoliating power, have been popular for a number of years, with a growing number of companies sneaking them into toothpaste, body scrubs, soap and more. That’s despite evidence that they cause significant environmental problems, an issue that’s led a number of states to ban them or seriously consider such bans in order to protect the environment. But there’s more: There’s evidence that microbeads are also harmful for human health.

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Connecting Elevation and Evolution

About 34 million years ago, global temperatures took a dive, causing a sudden wave of extinctions among European mammals. In North America, however, life went on largely unscathed. A new study explains why: The rise of the Rocky Mountains had forced North American mammals to adapt to a colder, drier world.

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Birds imitate alarm calls of others to warn of hawks

New research has found that the 6 gram brown thornbill mimics the hawk alarm calls of neighbouring species to scare a nest predator by convincing it that a much bigger and scarier predator - the brown goshawk - is on its way.

Currawongs, which raid the nests and hunt the chicks of thornbills, are also prey to goshawks. Although currawongs normally benefit from listening in on hawk alarm calls of other species, thornbills exploit this and turn it against them.

As well as issuing their own hawk alarm call, thornbills mimic those of the local species to create the impression of an impending hawk attack, which in turn distracts the pied currawong - a predator 40 times larger than the thornbill - providing thornbill nestlings with an opportunity to escape.

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Study relates influx of North American icebergs in Atlantic Ocean to increased methane production in tropical wetlands

A new study shows how huge influxes of fresh water into the North Atlantic Ocean from icebergs calving off North America during the last ice age had an unexpected effect – they increased the production of methane in the tropical wetlands. Usually increases in methane levels are linked to warming in the Northern Hemisphere, but scientists who are publishing their findings this week in the journal Science have identified rapid increases in methane during particularly cold intervals during the last ice age. These findings are important, researchers say, because they identify a critical piece of evidence for how the Earth responds to changes in climate.

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Fusion energy breakthrough

Researchers at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL) have for the first time simulated the formation of structures called "plasmoids" during Coaxial Helicity Injection (CHI), a process that could simplify the design of fusion facilities known as tokamaks. The findings, reported in the journal Physical Review Letters, involve the formation of plasmoids in the hot, charged plasma gas that fuels fusion reactions. These round structures carry current that could eliminate the need for solenoids - large magnetic coils that wind down the center of today's tokamaks - to initiate the plasma and complete the magnetic field that confines the hot gas.

"Understanding this behavior will help us produce plasmas that undergo fusion reactions indefinitely," said Fatima Ebrahimi, a physicist at both Princeton University and PPPL, and the paper's lead author. 

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