The fragile and rapidly changing Arctic region is home to large reservoirs of methane, a potent greenhouse gas. As Earth’s climate warms, the methane, frozen in reservoirs stored in Arctic tundra soils or marine sediments, is vulnerable to being released into the atmosphere, where it can add to global warming. Now a multi-institutional study by Eric Kort of NASA’s Jet Propulsion Laboratory, Pasadena, Calif., has uncovered a surprising and potentially important new source of Arctic methane: the ocean itself.(more…)
In ancient Earth history, the sun burned as much as 30 percent dimmer than it does now. Theoretically that should have encased the planet in ice, but there is geologic evidence for rivers and ocean sediments between 2 billion and 4 billion years ago.
Scientists have speculated that temperatures warm enough to maintain liquid water were the result of a much thicker atmosphere, high concentrations of greenhouse gases or a combination of the two. (more…)
*Tree trunks, leaves, and kukui nuts indirectly feed bottom fish in submarine canyons off Moloka’i*
Scientists from UH Mānoa’s School of Ocean and Earth Science and Technology (SOEST) recently discovered that land-based plant material and coastal macroalgae indirectly support the increased abundances of bottom fish in submarine canyons, like those off the north shore of Moloka’i. Less than a few miles from the shore, these underwater canyons connect to deep river valleys that cut across the landscape of north Moloka’i. The high elevation and forested landscapes along Moloka’i’s north shore provide plant material, including decomposing tree trunks, leaves and tons of kukui nuts, which enter the ocean via river valleys and “pile up” on submarine canyon floors. (more…)
When Sifrhippus sandae, the earliest known horse, first appeared in the forests of North America more than 50 million years ago, it would not have been mistaken for a Clydesdale.
It weighed in at around 12 pounds–and it was destined to get much smaller over the ensuing millennia.
Sifrhippus lived during the Paleocene-Eocene Thermal Maximum (PETM), a 175,000-year interval of time some 56 million years ago in which average global temperatures rose by about 10 degrees Fahrenheit. (more…)
*Engineers at Brown University have developed a system that cleanly and efficiently removes trace heavy metals from water. In experiments, the researchers showed the system reduced cadmium, copper, and nickel concentrations, returning contaminated water to near or below federally acceptable standards. The technique is scalable and has viable commercial applications, especially in the environmental remediation and metal recovery fields. Results appear in the Chemical Engineering Journal.*
PROVIDENCE, R.I. [Brown University] — An unfortunate consequence of many industrial and manufacturing practices, from textile factories to metalworking operations, is the release of heavy metals in waterways. Those metals can remain for decades, even centuries, in low but still dangerous concentrations.
Ridding water of trace metals “is really hard to do,” said Joseph Calo, professor emeritus of engineering who maintains an active laboratory at Brown. He noted the cost, inefficiency, and time needed for such efforts. “It’s like trying to put the genie back in the bottle.” (more…)
WASHINGTON — The deadly Russian heat wave of 2010 was due to a natural atmospheric phenomenon often associated with weather extremes, according to a new study. And while the scientists could not attribute the intensity of this particular heat wave to climate change, they found that extreme heat waves are likely to become increasingly frequent in the region in coming decades.
The research team drew from scientific observations and computer climate models to evaluate the possible roles of natural and human-caused climate influences on the severity of the heat wave. The study has been accepted for publication in Geophysical Research Letters, a journal of the American Geophysical Union. (more…)
Fireworks. Downtown Miami on July 4, 2007. Image credit: Marc Averette. Source: Wikipedia
Fireworks can be spectacular. However, the gas and smoke produced by the colorful explosions carry extremely high levels of toxic particles, according to a study by Audrey Smargiassi, a professor at the Université de Montreal Department of Environmental and Occupational Health.
Smargiassi conducted one of the first studies examining the composition of the emitted gases and the concentration of the particles. In addition, her study is unique as she collected her data below the fireworks display where spectators usually stand. Previous studies usually collected data from nearby rooftops.
The study was conducted in 2007 during nine separate shows presented at La Ronde amusement park where 5.7 million spectators attend an international fireworks competition every summer. (more…)
