WASHINGTON, D.C. Oct. 15, 2013 -- What do smoke rings, tornadoes and the Great Red Spot of Jupiter have in common? They are all examples of vortices, regions within a fluid (liquid, gas or plasma) where the flow spins around an imaginary straight or curved axis. Understanding how geophysical (natural world) vortices behave can be critical for tasks such as weather forecasting and environmental pollution monitoring.
Earth
Lightning strikes causing rocks to explode have for the first time been shown to play a huge role in shaping mountain landscapes in southern Africa, debunking previous assumptions that angular rock formations were necessarily caused by cold temperatures, and proving that mountains are a lot less stable than we think.
In a world where mountains are crucial to food security and water supply, this has vast implications, especially in the context of climate change.
Climate change affects forests across North America – in some cases permitting insect outbreaks, plant diseases, wildfires and other problems -- but Dartmouth researchers say warmer temperatures are also making many forests grow faster and some less susceptible to pests, which could boost forest health and acreage, timber harvests, carbon storage, water recycling and other forest benefits in some areas.
Boulder, Colo., USA – New Geosphere pre-issue publication articles are now online and include contributions to the CRevolution 2: Origin and Evolution of the Colorado River System II; Results of IODP Exp313: The History and Impact of Sea-level Change Offshore New Jersey; New Developments in Grenville Geology; and the Seeing the True Shape of Earth's Surface: Applications of Airborne and Terrestrial LiDAR in the Geosciences themed issues.
WASHINGTON, D.C. Oct. 15, 2013 -- Scientists studying the behavior of platinum particles immersed in hydrogen peroxide may have discovered a new way to propel microscopic machines. The new mechanism is described in The Journal of Chemical Physics, which is produced by AIP Publishing.
New research published today in the journal Quaternary Science Reviews has found the first evidence that large rivers control desert sands and dust in Northern China.
Northern China holds some of the world's most significant wind-blown dust deposits, known as loess. The origin of this loess-forming dust and its relationship to sand has previously been the subject of considerable debate.
EUGENE, Ore. -- (Oct. 11, 2013) -- A thorough examination of tiny crystals of zircon, a mineral found in rhyolites, an igneous rock, from the Snake River Plain has solidified evidence for a new way of looking at the life cycle of super-volcanic eruptions in the long track of the Yellowstone hotspot, say University of Oregon scientists.
Cambridge, Mass. – October 10, 2013 – Thirty-eight U.S. national parks are experiencing "accidental fertilization" at or above a critical threshold for ecological damage, according to a study published in the journal Atmospheric Chemistry and Physics and led by Harvard University researchers. Unless significant controls on ammonia emissions are introduced at a national level, they say, little improvement is likely between now and 2050.
A discovery at Rice University aims to make vehicles that run on compressed natural gas more practical. It might also prolong the shelf life of bottled beer and soda.
The Rice lab of chemist James Tour has enhanced a polymer material to make it far more impermeable to pressurized gas and far lighter than the metal in tanks now used to contain the gas.
The combination could be a boon for an auto industry under pressure to market consumer cars that use cheaper natural gas. It could also find a market in food and beverage packaging.
The iron in the Earth's inner core weakens dramatically before it melts, explaining the unusual properties that exist in the moon-sized solid centre of our planet that have, up until now, been difficult to understand.
Scientists use seismic waves - pulses of energy generated during earthquakes - to measure what is happening in the Earth's inner core, which at 6000 km beneath our feet is completely inaccessible.
In the land of 10,000 lakes, one lake has been the starting place for research with implications for big lakes around the world. According to a study published online this week in Science, University of Minnesota researchers, building from studies of nitrogen levels in Lake Superior, uncovered a good news/bad news scenario for lake health that has long-term, global implications for pollution control efforts.
One of the most controversial issues emerging from the recent Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5) is the failure of global climate models to predict a hiatus in warming of global surface temperatures since 1998. Several ideas have been put forward to explain this hiatus, including what the IPCC refers to as 'unpredictable climate variability' that is associated with large-scale circulation regimes in the atmosphere and ocean. The most familiar of these regimes is El Niño/La Niña, which are parts of an oscillation in the ocean-atmosphere system.
The volcano on the Scottish peninsula Ardnamurchan is a popular place for the study of rocks and structures in the core of a volcano. Geology students read about it in text books and geologists have been certain that the Ardnamurchan volcano have three successive magma chambers. However, an international group of researchers, lead from Uppsala University, Sweden, has now showed that the volcano only has one single magma chamber.
The new study is published in Scientific Reports, the new open access journal of the Nature Publishing Group.
A group of physicists from Canada have been growing their own icicles in a lab in the hope of solving a mystery that has, up until now, continued to puzzle scientists.
The presence of characteristic ripples along the surface of icicles, which remarkably have the same wavelength no matter how big the icicle or where in the world it grows, have led to several studies examining exactly how the ripples form.
Morris and Chen found that ripples only became apparent at the remarkably low salinity of the water with 20 mg of salt per litre. This level, in fact, is a considerably lower level of impurity than found in common tap water.
"We even added a non-ionic ingredient to the distilled water to reduce the surface tension of the thin film of water flowing over the icicle, and it didn't produce ripples," said Chen. "Instead, ripples emerge only on icicles grown from water with dissolved ionic impurities."