By Jerry James Stone •
August 10, 2009
The number of large-diameter trees in Yosemite National Park have declined 24-percent between the 1930s and 1990s.
The findings are based on a study done by the U.S. Geological Survey and the University of Washington. Scientists compared tree densities from 1932-1936 to those from 1988-1999 where large-diameter trees are those with a diameter greater than three feet.
Along with large-diameter tree loss, they also found a shift to fire-intolerant trees. Amazingly, this shift was experienced in areas that hadn’t seen a wildfire in nearly a century. Trees changed from fire-tolerant ponderosa pines to fire-intolerant white fir and incense cedar. In burned areas, however, the pines remained dominant.
World wide, 75 percent of human exposure to mercury is from the consumption of marine fish and shell fish. In the U.S., about 40 percent of all human exposure to mercury is from tuna harvested in the Pacific Ocean, according to Elsie Sunderland, a coauthor of the recent US Geologic Survey study.
Data used in this study comes from one of 15 (so far) research cruises that are part of a much larger, international project called CLIVAR; the Climate Variability (CLIVAR) Repeat Hydrography/CO2 research program.
Data analysis of the water samples indicated that total mercury levels in the North Pacific Ocean water have risen about 30 percent over the last 20 years.
By Dave Levitan •
April 12, 2009
The US Department of the Interior reports that they will start spending the stimulus money granted them in February, and among the $140 million-worth of projects is $15.2 million for Louisiana Governor Bobby Jindal’s favorite activity: volcano monitoring!
By Andrew Williams •
March 30, 2009
US Scientists have revealed how natural gas locked up in frozen water crystals could provide massive amounts of energy, and claim that it could even be totally emissions-free.
The astonishing claim was made by Tim Collett of the United States Geological Survey at last weeks national meeting of the American Chemical Society. Collett told the gathering that, to the naked eye, clathrate hydrate (CH) looks like everyday ice but, as well as being partly made of water, the molecules are also organised into “cages”, which trap individual molecules of methane.
Remarkably, a new method of extracting the methane and ’swapping’ it with carbon dioxide could turn the substance into a revolutionary carbon-neutral fossil fuel.
By Jennifer Lance •
December 26, 2008
Study finds melting ice in the Arctic and longer droughts in the Southwest indicate earlier projections have underestimated the climatic shifts that will take place by the end of the century.
By Tom Schueneman •
October 8, 2008
A study released last week from the U.S. Geological Survey reports that geothermal power production could significantly add to electric power generating capacity within the United States.
