Archive for US Geological Survey
www.latimes.com 29th January 2011
The US Geological Survey has tracked a female polar bear swimming for 426 miles in order to find an ice-flow in the Beaufort Sea. The epic journey took 9 days and came at a heavy cost. It was reported that she set out with her cub but the little one did not survive the trip. Furthermore, the length of her swim resulted in the bear losing 22% of her body weight. With little in the way of food at her destination, it is unlikely she will be able to recover. The marathon journey is yet another example of the extent ice is melting in the arctic region due to climate change. During the autumn open water periods in the region, polar bears are subject to either fasting on land until the ice reforms or swimming for ice-flows to find seals. With dramatic reduction in the size of ice-flows over the past few years, polar bears are finding it increasingly difficult to swim for food. The example of this 9-day swim is the most extreme recorded for the species. ”We have observed other long-distance swimming events. I don’t believe any of them have been as long in time and distance as what we observed with her,” George M. Durner, a USGS zoologist, said. The Obama administration has designated a 187,000 square miles of Alaska as a protection zone for the endangered polar bears but US District Judge Emmet G. Sulivan has ruled that the species must be in “imminent” danger of extinction before being given the status of endangered. The court battle between conservationist groups and oil and gas companies over this issue continues in February. If polar bears are declared endangered then the US will have to reduce its carbon emissions to protect the species.
e360.yale.edu 6th December 2010
Quoted from source:
‘A coal-based sealant sprayed on pavement for parking lots, playgrounds, and driveways is the leading contributor of a toxic pollutant found in U.S. lakes and reservoirs, according to a new study. Samples of sediments collected from the bottom of lakes and reservoirs in 40 urban areas by the U.S. Geological Survey revealed high levels of polycyclic aromatic hydrocarbons (PAHs), a probable carcinogen that is also toxic to fish and other marine life. On average, about half of the PAHs came from coal-tar sealants. Vehicles account for about one-fourth of the remaining pollutants, and coal combustion contributes about 20 percent, according to the study, published in the journal Science of the Total Environment. Coal-tar pavement sealants — derived from the waste produced in the coking of steel — have been banned in several U.S. cities, including Austin, Texas, and Washington, D.C. An alternate asphalt-based sealant contains levels of PAHs that are 1,000 times lower than coal-tar sealants.’