Atmospheric
A new paper estimates that fires in the continental United States and Alaska release about 44 metric tons of mercury into the atmosphere every year. It is the first study to estimate mercury emissions for each state, based on a new computer model developed at NCAR.
The authors caution that their estimates for the nation and for each state are preliminary and are subject to a 50 percent or greater margin of error.
Forest fires and other blazes in the United States likely release about 30 percent as much mercury as the nation's industrial sources, according to initial estimates in a new study…
Planetary scientists on both sides of the Atlantic have tracked down a rare molecule in the atmospheres of both Mars and Venus. The molecule, an exotic form of carbon dioxide, could affect the way the greenhouse mechanism works on Venus.
The discovery is being announced today at the annual meeting of the American Astronomical Society’s Division of Planetary Sciences in Orlando, Florida. Its presence could affect the way the greenhouse mechanism works on Venus. The mystery began back in April 2006, soon after ESA’s Venus Express arrived at the second planet in the Solar System.
A European…
Some of the elements necessary to support life on Earth are widely known - oxygen, carbon and water, to name a few. Just as important in the existence of life as any other component is the presence of adenine, an essential organic molecule. Without it, the basic building blocks of life would not come together. Scientists have been trying to find the origin of Earth's adenine and where else it might exist in the solar system. University of Missouri-Columbia researcher Rainer Glaser says he may have the answer.
Life exists on Earth because of a delicate combination of chemical ingredients.…
Deep-sea temperatures rose 1,300 years before atmospheric CO2, ruling out the greenhouse gas as the driver of the meltdown, says a new study.
“There has been this continual reference to the correspondence between CO2 and climate change as reflected in ice core records as justification for the role of CO2 in climate change,” said USC geologist Lowell Stott, lead author of the study, published in Science. “You can no longer argue that CO2 alone caused the end of the ice ages.”
Stott is an expert in paleoclimatology and was a reviewer for the Intergovernmental Panel on Climate Change ( IPCC ).…
An international team of researchers has determined there was a "whiff" of oxygen in Earth's atmosphere about 2.5 billion years ago, the earliest time any significant amount of oxygen has been detected on Earth. Up to now, scholars believed oxygen levels on Earth were negligible before the "Great Oxidation Event" (GOE) about 2.3 to 2.4 billion years ago.
This latest discovery indicates there was at least a little oxygen in Earth's atmosphere 50 to 100 million years before the GOE. It also provides scholars with more information to help them solve the mystery of the origins of oxygen on Earth…
The growth and conversion of biofuel crops could raise rather than lower greenhouse gas emissions, says a new study led by Nobel prize-winning chemist Paul Crutzen, best known for his work on the ozone layer.
He and his colleagues have calculated that growing some of the most commonly used biofuel crops releases around twice the amount of the potent greenhouse gas nitrous oxide (N2O, also known as ‘laughing gas’) than previously thought – wiping out any benefits from not using fossil fuels and, worse, probably contributing to global warming.
"The significance of it is that the supposed…
Scientists believe that shortly after Earth was formed, it had a glowing surface of molten rock extending down hundreds of miles. As that surface cooled, a rigid crust was produced near the surface and solidified slowly downward to complete the now-solid planet.
Some scientists have suggested that Earth lost all of its initial gases, either during the molten stage or as a consequence of a massive collision, and that the catastrophically expelled gases formed our early atmosphere and oceans. Others contend that this early “degassing” was incomplete, and that primordial gases still remain…
Observations and climate model results confirm that human-induced warming of the planet is having a pronounced effect on the atmosphere’s total moisture content.
“When you heat the planet, you increase the ability of the atmosphere to hold moisture,” said Benjamin Santer, lead author from Lawrence Livermore National Laboratory’s Program for Climate Modeling and Intercomparison. “The atmosphere’s water vapor content has increased by about 0.41 kilograms per cubic meter (kg/m²) per decade since 1988, and natural variability in climate just can’t explain this moisture change. The most plausible…
leebert |
Overturning the conventional theory that airborne soot emissions cause regional cooling it has been found that brown clouds of airborne soot can contribute up to a third of atmospheric warming anomalies in the tropics formerly ascribed to CO2 (50 percent of the atmospheric heating caused by CO2 emissions), with its effects ranging as far as the more-temperate American west coast and mountains ranges.
The lead researcher in this study, Prof. V. Ramanathan of the Scripps Institute commented, "The conventional thinking is that brown clouds have masked as much as 50 percent of the global…
leebert |
Easily 40 percent of the observed atmospheric warming in the Pacific is due to the shroud of soot drifting eastward from Asia. Prof. V. Ramanathan and fellow researchers are reporting that soot's 2.5 W/cu.m. green house effect is partially offset by its surface dimming effect, such that its net effect is still 1 W/cu.m. With the vast Pacific covering 30 percent of the Earth's surface, aerosol soot - black carbon particulates - plays a significant factor in global warming, potentially 12 percent of all global warming.
This westerly mid-atmospheric haze of soot is eventually depleted as it…