One of the largest and speediest fish, Pacific bluefin tuna can grow to 10 feet (3 meters) and weigh more than 1,000 pounds (450 kilograms). They spawn off the Japan coast and swim east at breakneck speed to school in waters off California and the tip of Baja California, Mexico.
Five months after the Fukushima disaster, Fisher of Stony Brook University in New York and a team decided to test Pacific bluefin that were caught off the coast of San Diego. To their surprise, tissue samples from all 15 tuna captured contained levels of two radioactive substances – ceisum-134 and caesium-137 – that were higher than in previous catches.
To rule out the possibility that the radiation was carried by ocean currents or deposited in the sea through the atmosphere, the team also analysed yellowfin tuna, found in the eastern Pacific, and bluefin that migrated to Southern California before the nuclear crisis. They found no trace of caesium-134 and only background levels of caesium-137 left over from nuclear weapons testing in the 1960s.
The results "are unequivocal. Fukushima was the source," said Ken Buesseler of the Woods Hole Oceanographic Institution, who had no role in the research.
Bluefin tuna absorbed radioactive caesium from swimming in contaminated waters and feeding on contaminated prey such as krill and squid, the scientists said. As the predators made the journey east, they shed some of the radiation through metabolism and as they grew larger. Even so, they weren't able to completely flush out all the contamination from their system.
"That's a big ocean. To swim across it and still retain these radionuclides is pretty amazing," Fisher said.
Pacific bluefin tuna are prized in Japan where a thin slice of the tender red meat prepared as sushi can fetch $24 per piece at top Tokyo restaurants. Japanese consume 80 per cent of the world's Pacific and Atlantic bluefin tuna.
The real test of how radioactivity affects tuna populations comes this summer when researchers planned to repeat the study with a larger number of samples. Bluefin tuna that journeyed last year were exposed to radiation for about a month. The forthcoming travellers have been swimming in radioactive waters for a longer period. How this will affect concentrations of contamination remains to be seen.
Now that scientists know that bluefin tuna can transport radiation, they also want to track the movements of other migratory species including sea turtles, sharks and seabirds.
Source: AP
Source: www.telegraph.co.uk
Competing tax plans try California voters - Financial Times
Source: www.ft.com
Banksy Artwork Of A Crane Discovered In Dorset - huffingtonpost.co.uk
The Banksy crane: not your typical street art
Never let it be said that Banksy doesn't experiment. The street art king's latest piece is an origami crane painted on a wall in a sleepy coastal down in Dorset.
No, we wouldn't have believed it either, but the creation has appeared on his official website - the stamp of authenticity Banksy fans wait for whenever a new stencil appears.
The crane, which holds a goldfish in its mouth, was spotted on the side of a building on a country path next to the River Lym in Lyme Regis.
Aside from the unusually rural setting, the crane contains none of the wry social or political undertones that characterizes most of Banksy's work, including his other most recent piece, the sweatshop worker child making bunting on the side of a London Poundland.
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All of which leads us to wonder: is this Banksy turning over a new leaf as an artist?
The crane is a bird with a rich history of symbolism around the world, not least of all in the home of origami.
Japanese folklore believes the crane lives for 1,000 year and is a symbol of happiness, good luck and peace.
Perhaps, then, it's a simply an expression of pastoral joy, a love letter to the British countryside. Maybe, just maybe, Banksy is turning from political satire to a form of street art romanticism.
Will Ellsworth-Jones, author of the new Banksy biography The Man Behind the Wall, told HuffPost UK that he didn't know what to make of the meaning behind the crane, but described it as an unusual and highly accomplished piece.
"It's actually a very difficult stencil to do. Look at the way it's been designed to reflect in the water," he said.
"A lot of thought gone into it. It just goes to show what a master of the stencil Banksy is."
Either way, his efforts will be welcomed by the people of Lyme Regis. New artworks by Banksy have been known to raise house prices, not to mention give the local tourist industry a welcome boost.
Do you have any ideas about the meaning of the origami crane? Give us your views below.
Source: www.huffingtonpost.co.uk
California, New Jersey still lead nation in solar contributions - ZDNet
California’s Pacific Gas & Electric (PG&E) remains the largest solar-generating utility in the United States, but New Jersey’s Public Service Gas & Electric (PSE&G) provides the most solar power per customer, according to a new ranking by the Solar Electric Power Association (SEPA).
The 2011 Utility Solar Rankings report showed that utilities across the United States connected approximately 62,000 photovoltaic systems into the grid during 2011, adding about 1,500 megawatts of new solar generation capacity. This represents the fourth straight year of increases, the SEPA analysis shows.
Approximately 40 percent of that capacity was from projects undertaken by the utilities themselves, compared with about 60 percent attributable to residential or commercial installations.
Here are the top 10 utilities in terms of annual solar megawatts produced. All three of the New Jersey utilities listed logged increases from 2010 and 2011; the two utilities at the bottom of the list leapt up substantially in the rankings.
- PG&E (287.7 megawatts installed)
- PG&E (181.3 megawatts)
- Arizona Public Services (144 megawatts)
- Southern California Edison (138 megawatts)
- Atlantic City Electric (61.2 megawatts)
- Jersey Central Power & Light (53 megawatts)
- Sacramento Municipal Utility District (52.8 megawatts)
- Xcel Energy - CO (51.3 megawatts)
- Long Island Power Authority (46.9 megawatts)
- Xcel Energy - NM (45.6 megawatts)
SEPA reported that the minimum amount of solar capacity in order to be listed on the ranking rose from 20 megawatts in 2010 to 45 megawatts in 2011.
Source: www.zdnet.com
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