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pgmrdlm shares a report from USA Today: Using special instruments, scientists have discovered weird sounds at the bottom of the world. The noise is actually vibrating ice, caused by the wind blowing across snow dunes, according to a new study. It's kind of like you're blowing a flute, constantly, on the ice shelf," study lead author Julien Chaput, a geophysicist and mathematician at Colorado State University, said in a statement. Another scientist, glaciologist Douglas MacAyeal of the University of Chicago, likened the sounds to the buzz of thousands of cicadas. The sounds are too low in frequency to be heard by human ears unless sped up by the monitoring equipment. The scientists originally buried 34 seismic sensors under the snow on Antarctica's Ross Ice Shelf to study the continent's ice shelves -- not to record the sounds they heard. "Studying the vibrations of an ice shelf's insulating snow jacket could give scientists a sense of how it is responding to changing climate conditions," reports USA Today. "Changes to the ice shelf's 'seismic hum' could also indicate whether cracks in the ice are forming that might indicate whether the ice shelf is susceptible to breaking up."

Geoffrey.landis writes: Last week a news story suggested that a new model of sunspot activity predicted a dramatic drop in solar activity coming up, possibly resulting in coming a mini-ice age. Take that prediction with a bit of skepticism, though-- later news analysis suggests that the story may be more media hype than science. Valentina Zharkova, the scientist whose research is being quoted, made no mention of a "mini Ice age"-- her work was only on modelling the solar dynamo. And, in any case, the solar minimum predicted was estimated to last only three solar cycles-- far less than the 17th century Maunder Minimum.

Phil Plait, known for his "bad astronomy" column, does a more detailed analysis of the claims, pointing out that the effect, if it even exists at all, is weak-- and the much discussed "Little Ice Age" is currently believed to most likely have been triggered by volcanic action, not sunspots. And, in any case, any predicted cooling is small compared to already-present global warming. So, probably no need to stock up on firewood, dried food, and ammunition quite yet-- the mini ice age isn't likely to be coming quite yet.

schwit1 writes: Scientists have found that, despite a complete ban since 2007, ozone-depleting chemicals are still being pumped into the atmosphere from some unknown source. "Carbon tetrachloride (CCl4), which was once used in applications such as dry cleaning and as a fire-extinguishing agent, was regulated in 1987 under the Montreal Protocol along with other chlorofluorocarbons that destroy ozone and contribute to the ozone hole over Antarctica. Parties to the Montreal Protocol reported zero new CCl4 emissions between 2007-2012. However, the new research shows worldwide emissions of CCl4 average 39 kilotons (about 43,000 U.S. tons) per year, approximately 30 percent of peak emissions prior to the international treaty going into effect. "We are not supposed to be seeing this at all," said Qing Liang, an atmospheric scientist at NASA's Goddard Space Flight Center in Greenbelt, Maryland, and lead author of the study published online in the Aug. 18 issue of Geophysical Research Letters, a journal of the American Geophysical Union. "It is now apparent there are either unidentified industrial leakages, large emissions from contaminated sites, or unknown CCl4 sources."

Hugh Pickens DOT Com writes "BBC reports that French scientists studying erosion on Mont Blanc have discovered that glaciers shield summits from erosion, acting as a protective lid and playing little part in erosion. In contrast, water and rain eroded glacier-free areas 10 times faster than areas protected by the glacier. These results may explain the high altitude of the Alps. Driven by the tectonic collision of Europe with Africa, the high alpine bedrock is rising about one millimeter each year. Glacier-free areas of the Alps erode at a similar rate but where the mountains are protected by ice, the peaks wear away at one tenth that rate. A long-term effect of this might be a rise in the maximum altitude of the Alps. 'However, mountains don't grow to infinity, so there must be another mechanism which has lowered the summit of Europe,' says Fritz Schlunegger. 'According to (Dr) Godon's findings, this erosion is not related to glaciers, so we still have to think about other possibilities.' Around the globe, mountain glaciers — especially those at low latitudes — are retreating in response to climate change. The glaciers around Mount Everest have lost more than one-eighth of their area in the past 50 years, and the snowline had retreated 180 meters up the mountain sides. The results suggest that changes like these could change the shapes of the world's highest mountains, and that climate and mountain landscape are intimately linked."

An anonymous reader writes "A new study released today (abstract) indicates that the Voyager 1 spacecraft has become the first man-made object to exit our solar system. Instrumentation data sent back to NASA indicate the historic event likely occurred on August 25, 2012, evidenced by drastic changes in radiation levels as the craft ventured past the heliopause. What remains to be seen, however, is whether Voyager 1 has actually made it to true interstellar space, or whether it has entered a separate, undefined region beyond our solar system. Either way, the achievement is truly monumental. 'It's outside the normal heliosphere, I would say that. We're in a new region,' said Bill Webber, professor emeritus of astronomy at New Mexico State University in Las Cruces. 'And everything we're measuring is different and exciting.'" Update: 03/20 20:44 GMT by S : Reader skade88 points out that the JPL Voyager team is not so sure: "It is the consensus of the Voyager science team that Voyager 1 has not yet left the solar system or reached interstellar space. In December 2012, the Voyager science team reported that Voyager 1 is within a new region called 'the magnetic highway' where energetic particles changed dramatically. A change in the direction of the magnetic field is the last critical indicator of reaching interstellar space and that change of direction has not yet been observed." So we'll probably be hearing about this again in a couple years.

cylonlover writes "We've heard reports that placing small, reflective particles into the upper atmosphere could actually improve crop yields, but would also significantly reduce the amount of electricity generated by solar power plants and do little to arrest the acidification of the world's oceans. Now another potential side effect has been theorized by Californian researchers, who say that solar geoengineering could lead to brighter, whiter skies, and sunsets with an afterglow (abstract)."

sciencehabit writes "China and India are some of the world's top polluters, with countless cars, factories, and households belching more than 2 million metric tons of carbon soot and other dark pollutants into the air every year. The pall hanging over the region has come to be known as 'the Asian brown cloud.' These pollutants aren't just bad news for the countries themselves. A new study reveals that they can affect climate thousands of kilometers away, warming the United States by up to 0.4C by 2024, while cooling other regions (abstract)."

New submitter S810 writes "According to an article in Discovery News, oxygen was found by the Cassini spacecraft around Dione, one of Saturn's large moons. 'It is thought the oxygen is being produced via interactions between Saturn's powerful radiation belts and Dione's water ice. The radiation breaks the water molecules down, liberating oxygen into the moon's exosphere.' Hopefully this will open the door for more funding of research int the moons of Saturn and Jupiter."

vikingpower writes "The Little Ice Age, lasting from the end of the Middle Age into the 17th century, may very likely have been caused by the combined effects of four major volcanic eruptions and increased sunlight reflection by increasing sea ice, the so-called Albedo effect. ... The University of Boulder has a press release with maps and photographs. Bette Otto-Bliesner, one of the scientists behind the 'volcano + sea ice' thesis, fields an earnest warning against drawing conclusions too quickly from this research: 'I think people might look at the Little Ice Age and think that all we need to save us from rising temperatures are some volcanic eruptions or the geo-engineering equivalent [...] But when you see what happened when global temperatures dropped by just one degree and you look at current predictions of six or seven degree increases for the future, you realize how precarious things are for life as we know it.'"

dtjohnson writes "A newly published study (abstract) predicts that solar storms are going to become increasingly disruptive to satellites and communications in the coming decades as the sun cycles towards a minimum of activity. 'The work, published in Geophysical Research Letters, predicts that once the Sun shifts toward an era of lower solar activity, more hazardous radiation will reach Earth. The team says the Sun is currently at a grand solar maximum. This phase began in the 1920s — and has lasted throughout the space age....The evidence seems to indicate that although there are fewer solar storms once the Sun leaves its grand maximum, they are more powerful, faster and therefore carry more particles.'"

polar red writes "22 years of banning CFCs is starting to pay off. Researchers have finally been able to measure a reduction in size of the ozone layer hole, after finding the source of its fluctuations. 'Salby's results reveal a fast decline in ozone levels until the late 1990s, then a slow rebound that closely matches what theoretical calculations had predicted, says David Karoly, a climate scientist at the University of Melbourne, Australia. "It is the sort of result that was expected, but is the first to provide detection of an increase in Antarctic ozone levels," he says.'"

carvalhao writes "The Register reports on a study from NASA and the US National Oceanic and Atmospheric Administration that claims that new climate models that account for the effects of increased CO2 levels on plant growth result on a 1.64 C increase for a doubling of CO2 concentrations, a far less gloomy scenario than previously considered."

jamie passes along this excerpt from DiscoveryNews: "If you thought the geysers and overblown threat of a supervolcanic eruption in Yellowstone National Park were dramatic, you ain't seen nothing: deep beneath Earth's surface, the hot spot that feeds the park has torn an entire tectonic plate in half. The revelation comes from a new study (abstract) in the journal Geophysical Research Letters that peered into the mantle beneath the Pacific Northwest to see what happens when ancient ocean crust from the Pacific Ocean runs headlong into a churning plume of ultra-hot mantle material."

Roland Piquepaille writes "In recent years, we have become increasingly dependent on applications using the Global Positioning System, such as railway control, highway traffic management, emergency response, and commercial aviation. But the American Geophysical Union warns us that we can't always trust our GPS gadgets because 'electrical activity in the... ionosphere can tamper with signals from GPS satellites.' However, new research studies are under way and 'may lead to regional predictions of reduced GPS reliability and accuracy.'" Roland's blog has useful links and a summary of a free introduction, up at the AGU site, to a special edition of the journal Space Weather with seven articles (not free) regarding ionospheric effects on GPS.

Roland Piquepaille writes "In recent years, we have become increasingly dependent on applications using the Global Positioning System, such as railway control, highway traffic management, emergency response, and commercial aviation. But the American Geophysical Union warns us that we can't always trust our GPS gadgets because 'electrical activity in the... ionosphere can tamper with signals from GPS satellites.' However, new research studies are under way and 'may lead to regional predictions of reduced GPS reliability and accuracy.'" Roland's blog has useful links and a summary of a free introduction, up at the AGU site, to a special edition of the journal Space Weather with seven articles (not free) regarding ionospheric effects on GPS.

esocid writes "A team of European scientists has deliberately triggered electrical activity in thunderclouds for the first time by aiming high-power pulses of laser light into a thunderstorm. At the top of South Baldy Peak in New Mexico during two passing thunderstorms, the researchers used laser pulses to create plasma filaments that could conduct electricity. No air-to-ground lightning was triggered because the filaments were too short-lived, but the laser pulses generated discharges in the thunderclouds themselves up to several meters long. Triggering lightning strikes is an important tool for basic and applied research because it enables researchers to study the mechanisms underlying lightning strikes. Moreover, triggered lightning strikes will allow engineers to evaluate and test the lightning-sensitivity of airplanes and critical infrastructure such as power lines. Research into laser-triggered lightning has been going on for some years. Until now, no experiment was able to produce a long enough plasma channel to affect the electrical activity inside clouds."

Frosty Piss writes "Supervolcanoes can sleep for centuries or millennia before producing incredibly massive eruptions that can drop ash across an entire continent. One of the largest supervolcanoes in the world lies beneath Yellowstone National Park. Significant activity continues beneath the surface. And the activity has been increasing lately, scientists have discovered. In addition, the nearby Teton Range of mountains is somehow getting shorter. The findings, reported this month in the Journal of Journal of Geophysical Research, suggest that a slow and gradual movement of a volcano over time can shape a landscape more than a violent eruption."

dusty writes "A recent hypothesis paper entititled 'Martian CH4: Sources, Flux, and Detection' delves into the production of methane on Mars. This hypothesis compares Mars with South Africa, and draws the conclusion that the radiolysis of martian ice and water while reacting with carbon dioxide can produce enough methane to account for recently observed concentrations. Methane is important because it is hard to explain. It has a short half-life and must be replenished frequently. As recently as 2005 the public line from NASA/JPL was that the methane could be produced by volcanism. Mars' dormant Olympus Mons is the largest volcano in the solar system but auspiciously quiet. A recent study from NOAA throws into question the whole idea stating, 'If Mauna Loa is a valid terrestrial analog, our findings suggest that volcanic activity is not a significant source of methane to the Martian atmosphere.'"

PenguinRadio writes "The San Francisco Chronicle is reporting on a 37-mile long fissure that split open in September in the Afar desert in Ethiopia that could be the start of a new ocean forming. The fissure, which grew 8 meters wide in 3 weeks following an earthquake on Sept 14, is now splitting at about 0.8 inches per year, would eventually lead to Ethiopia eastern portions becoming an island in a million years or so. The findings were presented at the American Geophysical Union meeting taking place in San Francisco this week. The BBC reports that formation of a ocean basin is the first step toward developing an ocean, but that it will be millions of years before that could occur."

SubstormGuy writes "In a scientific session at the AGU meeting in New Orleans this morning, Dr. Ed Stone presented clear evidence that Voyager 1 crossed the termination shock last December. The scientists in the room applauded when the announcement was made."

Abhishek writes "Space.com reports that forecasters who predict the Solar weather can rely on Jupiter now to help them see the part of the sun that is not visible due to Earth's rotation and revolution and sun's rotation along its own axis. Scientists observing the X-Ray emanating from the Jovian atmosphere theorised that those coming from the equator were related to solar activity but it is definitely not a perfect mirror; only one in every few thousand X-Ray photons get reflected. But even that is very useful in predicting the solar weather. 'We found that Jupiter's day-to-day disk X-rays were synchronized with the Sun's emissions,' said Anil Bhardwaj at NASA Marshall Space Flight Center, who led a new study using data from the European Space Agency's XMM-Newton telescope. Their work was detailed in Geophysical Research Letters."

Sleen writes: "A new study that will appear in today's issue of the journal Science reports that the mass extinction event that preceded the age of the dinosaurs was much more sudden than expected. This article has some preliminary details. The dinosaurs actually survived this event and went on to be quite successful. But the small mammal-like reptiles did not. At this point they don't know if this cataclysm was caused by an asteroid, like in the case of 65mya at the KT boundary, or if it was caused by excessive volcanism. In the case of the dinosaur extinctions, they were on their way down when the asteroid hit, perhaps being the last straw. But this earlier event that somehow wiped out up to 80% of life on earth didn't kill them off. Interesting..."