Scientists have long speculated as to why animal species didn’t flourish sooner, once sufficient oxygen covered the Earth’s surface. Animals began to prosper at the end of the Proterozoic period, about 800 million years ago. But what about the billion-year stretch before that, when most researchers think there also was plenty of oxygen? Well, it seems the air wasn’t so great then, after all.
By remotely "combing" the atmosphere with a custom laser-based instrument, researchers from NIST...
Nitrogen is an essential component of all living systems, playing important roles in everything...
Scientists have identified an unexpected high-altitude methane ice cloud on Saturn's moon Titan...
Since the first undersea methane seep was discovered 30 years ago, scientists have meticulously analyzed and measured how microbes in the seafloor sediments consume the greenhouse gas methane as part of understanding how the Earth works. The sediment-based microbes form an important methane “sink,” preventing much of the chemical from reaching the atmosphere and contributing to greenhouse gas accumulation.
The findings of NASA’s planet-hunting Kepler spacecraft suggest that the most common exoplanets are those that are just a bit larger than Earth but smaller than Neptune. These so-called super-Earths, which do not exist in our own solar system, have attracted the attention of astronomers, who have been trying to determine the composition of the closest of these planets. However, an unexpected barrier is blocking their progress.
A surprising hot spot of the potent global-warming gas methane hovers over part of the southwestern U.S., according to satellite data. That result hints that the U.S. Environmental Protection Agency and other agencies considerably underestimate leaks of methane, also called natural gas. While methane isn't the most plentiful heat-trapping gas, scientists worry about its increasing amounts and have had difficulties tracking emissions.
An improved theoretical model of photoabsorption of nitrous oxide, developed by scientists in Malaysia, could shed light on the atmospheric chemistry of ozone depletion. The new theoretical work unveils, through improvements in established calculation approaches, the actual dynamic of stratospheric catalytic ozone destruction.
Scientists at the U.S. Department of Energy’s Argonne National Laboratory have created a new model to more accurately describe the greenhouse gases likely to be released from Arctic peatlands as they warm. Their findings, based on modeling how oxygen filters through soil, suggest that previous models probably underestimated methane emissions and overrepresented carbon dioxide emissions from these regions.
Over the past 40 years, researchers have thought that there must have been a small amount of oxygen in the atmosphere of early Earth to help give rise to plant life. But oxygen reacts aggressively with other compounds and disappears without a continuous source, so where did this abiotic, or “non-life”, oxygen come from? Chemists in California have now shown how ultraviolet light can split carbon dioxide to form oxygen in one step.
Mathematicians from Brown Univ. have introduced a new element of uncertainty into an equation used to describe the behavior of fluid flows. Ironically, allowing uncertainty into a mathematical equation that models fluid flows makes the equation much more capable of correctly reflecting the natural world, including the formation, strength, and position of air masses and fronts in the atmosphere.
The atmospheric conditions associated with the unprecedented drought currently afflicting California are "very likely" linked to human-caused climate change, according to Stanford Univ. scientists. The team used a combination of computer simulations and statistical techniques to show that a persistent region of high atmospheric pressure hovering over the Pacific Ocean was likely to form from modern greenhouse gas concentrations.
Astronomers using data from NASA's space telescopes Hubble, Spitzer, and Kepler have discovered clear skies and steamy water vapor on a gaseous planet outside our solar system. The planet is about the size of Neptune, making it the smallest planet from which molecules of any kind have been detected.
Researchers may soon have a better idea of how tiny particles of pollution are formed in the atmosphere. These particles, called aerosols, are hazardous to human health and contribute to climate change, but researchers know little about how their properties are shaped by chemical reactions in the atmosphere. Unraveling this chemistry could someday lead to more effective policies to protect human health and the Earth’s climate.
The robotic explorer Maven successfully slipped into orbit around Mars late Sunday night. Now the real work begins for the $671 million mission, the first dedicated to studying the Martian upper atmosphere and the latest step in NASA's bid to send astronauts to Mars in the 2030s. Researchers hope to learn where all the red planet's water went, along with the carbon dioxide that once comprised an atmosphere thick enough to hold moist clouds.
Researchers from the Univ. of Cambridge have developed advanced molecular synthetic membranes, or “sieves”, which could be used to filter carbon dioxide and other greenhouse gases from the atmosphere. The sieves were made by heating microporous polymers using low levels of oxygen which, produces a tougher and far more selective membrane that is still relatively flexible.
The production and consumption of chemical substances threatening the ozone layer has been regulated since 1987 in the Montreal Protocol. Eight international expert reports have since been published, the most recent of which was presented on Sept. 10 at the United Nations Headquarters in New York. Model calculations reveal that by 2050 the ozone layer may return to its 1980 levels.
Remember the polar vortex, the huge mass of Arctic air that can plunge much of the U.S. into the deep freeze? You might have to get used to it. A new study says that as the world gets warmer, parts of North America, Europe and Asia could see more frequent and stronger visits of that cold air. Researchers say that's because of shrinking ice in the seas off Russia.
According to Univ. of California Irvine and Princeton Univ. scientists, existing power plants around the world will pump out more than 300 billion tons of carbon dioxide over their expected lifetimes, significantly adding to atmospheric levels of the climate-warming gas. The findings are the first to quantify how quickly these "committed" emissions are growing.
Lower rates of asthma and other health problems are frequently cited as benefits of policies aimed at cutting carbon emissions from sources like power plants and vehicles, because these policies also lead to reductions in other harmful types of air pollution. But just how large are the health benefits of cleaner air in comparison to the costs of reducing carbon emissions?
Just how much Arctic permafrost will thaw in the future and how fast heat-trapping carbon dioxide will be released from those warming soils is a topic of lively debate among climate scientists. To answer those questions, scientists need to understand the mechanisms that control the conversion of organic soil carbon into carbon dioxide gas. Until now, researchers believed that bacteria were largely responsible.
Under the right scenario, exporting U.S. coal to power plants in South Korea could lead to a 21% drop in greenhouse gas emissions compared to burning the fossil fuel at plants in the U.S., according to a new Duke Univ.-led study. For the reduction to occur, U.S. plants would need to replace the exported coal with natural gas. And in South Korea, the imported coal must replace other coal as the power source.
Previous research into the health impacts of in utero exposure to the 9/11 dust cloud on birth outcomes has shown little evidence of consistent effects. But according to a new paper pregnant women living near the World Trade Center during 9/11 experienced higher-than-normal negative birth outcomes. These mothers were more likely to give birth prematurely and deliver babies with low birth weights.
Putting three radars on a plane to measure rainfall may seem like overkill. But for the Integrated Precipitation and Hydrology Experiment field campaign in North Carolina recently, more definitely was better. The system is specifically designed to measure rain in difficult-to-forecast mountain regions, where a wide range of frequencies to need be covered so that researchers can detect the more than 30 varieties of rainfall.
A Florida State Univ. geography professor has shown that climate change may be playing a key role in the strength and frequency of tornadoes hitting the United States. though tornadoes are forming fewer days per year, they are forming at a greater density and strength than ever before. Instead of one or two forming on a given day in an area, there might be three or four occurring.
Scientists have uncovered key attributes of so-called “brown carbon” from wildfires, airborne atmospheric particles that may have influenced current climate models that failed to take the material’s warming effects into account. The work was described by a collaborative team of researchers from Los Alamos National Laboratory, Carnegie Mellon Univ. and the Univ. of Montana in Nature Geosciences.
Aerosols, tiny particles in the atmosphere, play a significant role in Earth's climate, scattering and absorbing incoming sunlight and affecting the formation and properties of clouds. Currently, the effect that these aerosols have on clouds represents the largest uncertainty among all influences on climate change.
Norwegian explorer Roald Amundsen became the first man to reach the South Pole in December 1911. More than 100 years later, an international team of scientists that includes a NASA researcher has proven that air pollution from industrial activities arrived to the planet’s southern pole long before any human.
Many studies have shown the potential for global climate change to cut food supplies. But these studies have, for the most part, ignored the interactions between increasing temperature and air pollution. A new study shows that these interactions can be quite significant, suggesting that policymakers need to take both warming and air pollution into account in addressing food security.
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