More than two decades have passed since the infamous Exxon Valdez oil spill in Prince William Sound. Although 38,000 tons (11 million gallons) of crude oil were spilled, given time and the cleanup effort, it was assumed that the spill would be gone in a few years. Unfortunately, the oil has been very slow to disperse and about 20,000 gallons still remain. A new study offers an explanation for this fact. Th reason to due to the composition of the beaches at Prince William Sound. The beaches there have two layers of rock, with larger rocks on top and finer gravel underneath. Water, which could have broken up the oil, moves through the bottom layer 1,000 time slower than the top. When the oil entered the lower level of fine gravel it compacted even further and the elements necessary for the oil to biodegrade were limited.
Posted tagged ‘Alaska’
A new study that analyzed DNA samples recovered from Alaskan permafrost suggests that megafauna such as woolly mammoths and ancient horses did not die off around 13,000 years ago as is commonly thought. Instead, these animals were living in central Alaska about 10,000 years ago. The new evidence suggest that they also could have lived as recently as 7,600 years ago. The new study, rather than analyzing fossilized remains of an animal, analyzed DNA in the form of skin cells and feces in the permafrost samples. The researchers conducting the study turned to permafrost because of the difficulty of finding the fossilized remains of the last Ice Age megafauna.
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Last week the Obama administration proposed protecting 200,000 miles in Alaska as critical habitat for polar bears. This designation could restrict off-shore gas and oil drilling. While welcomed by environmentalists, this decision is not without controversy, both for environmentalists and those opposed to limiting drilling. For more information, see the Scientific American.
A study by Jeremy Mathis, a chemical oceanographer at the University of Alaska-Fairbanks, suggests that colder Alaskan waters are absorbing greenhouse gases faster than tropical waters, turning those colder water more acidic. Oceans absorb carbon dioxide, approximately 22 million tons per day. When that carbon dioxide is dissolved in the ocean, it forms carbonic acid. According to studies, increased levels of acid have been known to increase stress hormones and slow metabolisms in certain species of ocean life. For more information on this study & its impact on Alaska, see RedOrbit.
Significant numbers of Alaskan king salmon have failed to return to spawning grounds this year. This poor return by the salmon follows two years of similar low returns. Biologists speculate that the likely reason for the plummet is a current shift in the Pacific Ocean. But, they caution that there could be other reasons including: food availability, changes in river conditions, or changes in predators. Local residents blame the nets used for pollock fishing that catch large numbers of salmon by accident. For more information on the king salmon, see redOrbit.
Another significant eruption on Saturday signals that Mt. Redoubt is showing no signs of stopping. An ash cloud was sent 50,000 feet into the air. Typically, when Mt. Redoubt enters an eruption phase, it erupts for months. So, Alaskans are likely to experience many more eruptions by Mt. Redoubt.
First, Mt. Redoubt continued to erupt several times on Saturday, March 28, sending volcanic ash to Anchorage, 100 miles to the northeast. The ash plume was 45,000 to 50,000 feet high on Saturday. After the first eruption, there was also strong seismic activity. The Ted Stevens Anchorage International Airport shut down due to the ash, but reopened on Sunday and is expected to be fully operational on Tuesday. On Sunday, Mt. Redoubt did not erupt, but it did have low-level tremors. For more information, see the Associated Press article here.
Second, the Space Shuttle Discovery landed in Florida on Saturday, ending its 13 day mission to the International Space Station (ISS). Discovery brought Dr. Sandra Magnus back to Earth after four months in space at the International Space Station. She was replaced aboard the ISS by Koichi Wakata, a Japanese astronaut, who arrived via Discovery. Additionally, a Russian Soyuz capsule with an American tourist on board has docked safely at the International Space Station just a few days after Discovery’s departure. For more information, see here.