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…)
Earth’s clouds got a little lower — about one percent on average — during the first decade of this century, finds a new NASA-funded university study based on NASA satellite data. The results have potential implications for future global climate.
Scientists at the University of Auckland in New Zealand analyzed the first 10 years of global cloud-top height measurements (from March 2000 to February 2010) from the Multi-angle Imaging SpectroRadiometer (MISR) instrument on NASA’s Terra spacecraft. The study, published recently in the journal Geophysical Research Letters, revealed an overall trend of decreasing cloud height. Global average cloud height declined by around one percent over the decade, or by around 100 to 130 feet (30 to 40 meters). Most of the reduction was due to fewer clouds occurring at very high altitudes. (more…)
History of influence of industrial revolution hidden in glacial ice
New clues about how Earth’s remote ecosystems have been influenced by the industrial revolution have been uncovered. Until now they were locked away, frozen in the ice of glaciers.(more…)
VANCOUVER, British Columbia — Hydraulic fracturing of shale formations to extract natural gas has no direct connection to reports of groundwater contamination, based on evidence reviewed in a study released Thursday by the Energy Institute at The University of Texas at Austin.(more…)
PASADENA, Calif. – A NASA-led science team has created an accurate, high-resolution map of the height of Earth’s forests. The map will help scientists better understand the role forests play in climate change and how their heights influence wildlife habitats within them, while also helping them quantify the carbon stored in Earth’s vegetation.
Scientists from NASA’s Jet Propulsion Laboratory, Pasadena, Calif.; the University of Maryland, College Park; and Woods Hole Research Center, Falmouth, Mass., created the map using 2.5 million carefully screened, globally distributed laser pulse measurements from space. The light detection and ranging (lidar) data were collected in 2005 by the Geoscience Laser Altimeter System instrument on NASA’s Ice, Cloud and land Elevation Satellite (ICESat). (more…)
*Four new reports examine the contaminants polycyclic aromatic hydrocarbons (PAHs) found in house dust, streams, lakes, soil, and air*
Coal-tar-based sealants are emitting polycyclic aromatic hydrocarbons (PAHs) into the air at rates that may be greater than annual emissions from vehicles in the United States, according to new reports by the U.S. Geological Survey, published in the scientific journals Chemosphere and Atmospheric Environment.(more…)
A Yale-led study of the evolutionary history of Antarctic fish and their “anti-freeze” proteins illustrates how tens of millions of years ago a lineage of fish adapted to newly formed polar conditions – and how today they are endangered by a rapid rise in ocean temperatures.(more…)
EAST LANSING, Mich. — Many people are willing to pay a premium for ethanol, but not enough to justify the government mandate for the corn-based fuel, a Michigan State University economist argues.
Soren Anderson studied the demand for ethanol, or E85, in the United States. He found that when ethanol prices rose 10 cents per gallon, demand for ethanol fell only 12 percent to 16 percent on average. (more…)
