Atmospheric Sciences
Scientists produce densest artificial ionospheric plasma clouds yet
February 25, 2013 11:56 am | News | Comments
U.S. Naval Research Laboratory research physicists and engineers from the Plasma Physics Division, working at the High-frequency Active Auroral Research Program (HAARP) transmitter facility in Alaska have successfully produced a sustained high density plasma cloud in Earth's upper atmosphere. Previous attempts generated clouds with lifetimes of 10 minutes or less; this one lasted for more than one hour.
Researchers explain magnetic field misbehavior in solar flares
May 23, 2013 8:39 am | News | Comments
When a solar flare filled with charged particles erupts from the sun, its magnetic...
Power of Moore tornado dwarfs Hiroshima bomb
May 22, 2013 11:16 am | by Seth Borenstein, AP Science Writer | News | Comments
On Tuesday, the National Weather Service gave the recent Moore, Okla., tornado the top...
Amazon River exhales virtually all carbon taken up by rain forest
May 21, 2013 2:58 pm | by Hannah Hickey, University of Washington | News | Comments
Until recently people believed much of the rain...
Weather on the outer planets only goes so deep
May 16, 2013 12:31 pm | News | CommentsThe planets Uranus and Neptune are home to extreme winds blowing at speeds of over 1,000 km/hour, hurricane-like storms as large around as Earth, immense weather systems that last for years, and fast-flowing jet streams. Researchers using a new method for analyzing the gravitational field of these planets have determined an upper limit for the thickness of the atmospheric layer, which limits the depth of stormy weather.
Innovation in spectroscopy could improve greenhouse gas detection
May 15, 2013 8:37 am | News | CommentsDetecting greenhouse gases in the atmosphere could soon become far easier with the help of an innovative technique developed by a team at NIST, where scientists have overcome an issue preventing the effective use of lasers to rapidly scan samples. The team says the technique also could work for other jobs that require gas detection, including the search for hidden explosives and monitoring chemical processes in industry and the environment.
Study traces origin of cirrus clouds
May 9, 2013 2:48 pm | News | CommentsResearchers studying the origin of cirrus clouds have found that these thin, wispy trails of ice crystals are formed primarily on dust particles and some unusual combinations of metal particles—both of which may be influenced by human activities. The findings are important, scientists say, because cirrus clouds cover as much as one-third of the Earth and play an important role in global climate.
Discovered: Unexpected cooling effect on climate
May 7, 2013 8:11 am | News | CommentsUniversity of Manchester scientists, writing in Nature Geoscience, have shown that natural emissions and manmade pollutants can both have an unexpected cooling effect on the world’s climate by making clouds brighter. Clouds are made of water droplets, condensed on to tiny particles suspended in the air. When the air is humid enough, the particles swell into cloud droplets.
Cleaner energy, warmer climate?
May 7, 2013 7:17 am | by Vicki Ekstrom, Joint Program on the Science and Policy of Global Change | News | CommentsThe growing global demand for energy, combined with a need to reduce emissions and lessen the effects of climate change, has increased focus on cleaner energy sources. But what unintended consequences could these cleaner sources have on the changing climate? Researchers at Massachusetts Institute of Technology now have some answers to that question, using biofuels as a test case.
Study finds “dark oxidants” form away from sunlight, in oceans and underground
May 6, 2013 9:26 am | News | CommentsAll forms of life that breathe oxygen—even ones that can't be seen with the naked eye, such as bacteria—must fight oxidants to live. These same oxidants also exist in the environment. But neutralizing environmental oxidants such as superoxide was a worry only for organisms that dwell in sunlight—in habitats that cover a mere 5% of the planet. Now researchers have discovered the first light-independent source of superoxide.
Meteorite study may reveal Mars’ secrets of life
May 2, 2013 8:57 am | News | CommentsIn an effort to determine if conditions were ever right on Mars to sustain life, a team of scientists has examined a meteorite that formed on the red planet more than a billion years ago. And although this team’s work is not specifically solving the mystery, it is laying the groundwork for future researchers to answer this age-old question.
Air pollution linked to hardening of arteries
April 25, 2013 11:03 am | News | CommentsLong-term exposure to air pollution may be linked to heart attacks and strokes by speeding up atherosclerosis, or "hardening of the arteries," according to a University of Michigan public health researcher and colleagues from across the U.S.
Analysis of 2,000 years of climate records reveals end of global cooling trend
April 24, 2013 8:58 am | News | CommentsThe most comprehensive evaluation of temperature change on Earth’s continents over the past 1,000 to 2,000 years indicates that a long-term cooling trend—caused by factors including fluctuations in the amount and distribution of heat from the sun, and increases in volcanic activity—ended late in the 19th century.
Nitrogen has key role in estimating CO2 emissions from land use change
April 23, 2013 9:42 am | News | CommentsA new global-scale modeling study that takes into account nitrogen—a key nutrient for plants—estimates that carbon emissions from human activities on land were 40% higher in the 1990s than in studies that did not account for nitrogen. Most existing models used to estimate global emissions changes based on land use do not have the ability to model nitrogen limitations on plant regrowth.
Scientists discover new materials to capture methane
April 16, 2013 12:52 pm | News | CommentsScientists at Lawrence Livermore National Laboratory and the University of California, Berkeley have discovered new materials to capture methane, the second highest concentration greenhouse gas emitted into the atmosphere. The research team performed systematic computer simulation studies on the effectiveness of methane capture using two different materials—liquid solvents and nanoporous zeolites.
Sunlit snow triggers atmospheric cleaning, ozone depletion in the Arctic
April 15, 2013 4:23 pm | News | CommentsA Purdue University-led team of researchers discovered sunlit snow to be the major source of atmospheric bromine in the Arctic, the key to unique chemical reactions that purge pollutants and destroy ozone. The team's findings suggest the rapidly changing Arctic climate—where surface temperatures are rising three times faster than the global average—could dramatically change its atmospheric chemistry.
Report: Cutting specific atmospheric pollutants would slow sea level rise
April 15, 2013 12:56 pm | News | CommentsNew research indicates that cutting emissions of certain pollutants can greatly slow sea level rise this century. Scientists focussing on emissions of four heat-trapping pollutants—methane, tropospheric ozone, hydrofluorocarbons, and black carbon—found that reductions these pollutants that cycle comparatively quickly through the atmosphere could temporarily forestall the rate of sea level rise by roughly 25 to 50%.
Researchers measure reaction rates of second key atmospheric component
April 12, 2013 8:14 am | News | CommentsResearchers have successfully measured reaction rates of a second Criegee intermediate, CH3CHOO, and proven that the reactivity of the atmospheric chemical depends strongly on which way the molecule is twisted. The measurements will provide further insight into hydrocarbon combustion and atmospheric chemistry.
Ocean nutrients a key component of future change. say scientists
April 11, 2013 2:18 am | News | CommentsVariations in nutrient availability in the world's oceans could be a vital component of future environmental change, according a research team. Their research reviews what we know about ocean nutrient patterns and interactions, and how they might be influenced by future climate change and other man-made factors. The authors also highlight how nutrient cycles influence climate by fuelling biological production.
Widely used index may have overestimated drought
April 8, 2013 6:26 pm | News | CommentsFor decades, scientists have used sophisticated instruments and computer models to predict the nature of droughts. The majority of these models have steadily predicted an increasingly frequent and severe global drought cycle. But a recent study from a team of researchers in the United State and Australia suggests that one of these widely used tools—the Palmer Drought Severity Index (PDSI)—may be incorrect.
Thin, low Arctic clouds an important key to Greenland Ice Sheet melt
April 5, 2013 6:06 pm | News | CommentsAccording to a new study by scientists funded by the National Science Foundation (NSF) and at the National Oceanic and Atmospheric Administration (NOAA), clouds over the central Greenland Ice Sheet last July were "just right" for driving surface temperatures there above the melting point. The 2012 melt illustrates the often-overlooked role that clouds play in climate change. Current models don’t do enough, says researchers, to account for their effects.
NASA team investigates complex chemistry at Titan
April 3, 2013 6:06 pm | News | CommentsA laboratory experiment at NASA's Jet Propulsion Laboratory, Pasadena, Calif., simulating the atmosphere of Saturn's moon Titan suggests complex organic chemistry that could eventually lead to the building blocks of life extends lower in the atmosphere than previously thought. The results now point out another region on the moon that could brew up prebiotic materials.
New models predict drastically greener Arctic in coming decades
March 31, 2013 6:48 pm | News | CommentsResearchers from several universities, AT&T Labs, and the American Museum of Natural History have built new models that show a widespread redistribution of Arctic vegetation. They say their findings predict a massive “greening” in the Arctic, as much as 50% in over the next few decades. This transition will help accelerate climate warming, they add.
A new method for measuring the viscosity of nanoparticles
March 28, 2013 9:18 am | News | CommentsFor the first time, scientists measured the chemical diffusivity and viscosity of atmospheric organic particles, thanks to a new approach from scientists at Pacific Northwest National Laboratory, University of Washington, and Imre Consulting. The team doped atmospherically important organic nanoparticles, known as secondary organic aerosols, with tracer molecules and measured their diffusion rate as they slowly worked their way out of the particles. Knowing the diffusion rate, the scientists calculated the particle's viscosity.
Measuring Mars: The MAVEN magnetometer takes shape
March 27, 2013 7:40 am | by Claire De Saravia, NASA's Goddard Space Flight Center | News | CommentsScheduled for launch in late 2013, the Mars Atmosphere and Volatile Evolution (MAVEN) mission will carry a sensitive magnetic-field instrument built and tested by a team at NASA’s Goddard Space Flight Center. Very little magnetic field traces remain on Mars, which is forcing NASA to eliminate all magnetic traces from its spacecraft. The magnetometer may help determine the history of the loss of atmospheric gases to space through time, providing answers about Mars’ climate evolution.
Fake Shewanella reveals how bacteria breathe iron
March 26, 2013 8:13 am | News | CommentsCertain bacteria can breathe iron like we breathe oxygen. Understanding how they do so will help researchers use the microbes for cleaning up soil contaminants, for trapping carbon dioxide, or for making batteries out of bacteria. Now, a team of researchers report that proteins on the surface of bacteria produce an electric current by simply touching a mineral surface, allowing them to breathe the iron in the rock.
Could global warming change tornado season, too?
March 18, 2013 9:12 am | by Seth Borenstein, AP Science Writer | News | CommentsWith the planet heating up, many scientists seem fairly certain some weather elements like hurricanes and droughts will worsen. But tornadoes have them stumped. As the traditional tornado season nears, scientists have been pondering a simple question: Will there be more or fewer twisters as global warming increases?
Earth warmer today than during most of past 11,300 years
March 8, 2013 9:55 am | News | CommentsWith data from 73 ice and sediment core monitoring sites around the world, scientists have recently reconstructed Earth's temperature history back to the end of the last Ice Age. The analysis reveals that the planet today is warmer than it's been during 70 to 80% of the last 11,300 years.
Waves generated by Russian meteor recorded in U.S.
March 7, 2013 10:44 am | News | CommentsWhile thousands of earthquakes around the globe are recorded by seismometers in these stations—part of the permanent Global Seismographic Network (GSN) and EarthScope's temporary Transportable Array (TA)—signals from large meteor impacts are far less common. The meteor explosion near Chelyabinsk on Feb. 15, 2013, generated ground motions and air pressure waves in the atmosphere. The stations picked up the signals with seismometers and air pressure sensors, and recorded the pressures waves as they cross the United States.
