FILE - In this Sept. 2001 file photo provided by provided by Queensland Tourism, an aerial view shows the Great Barrier Reef off Australia's Queensland state. Ocean acidification has emerged as one of... more 
FILE - In this Sept. 2001 file photo provided by provided by Queensland Tourism, an aerial view shows the Great Barrier Reef off Australia's Queensland state. Ocean acidification has emerged as one of the biggest threats to coral reefs across the world, acting as the "osteoporosis of the sea" and threatening everything from food security to tourism to livelihoods, the head of a U.S. scientific agency said Monday, July 9, 2012. (AP Photo/Queensland Tourism, File) less 
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Associated Press | Photo By Queensland Tourism, File
Mon, Jul 9, 2012 1:47 AM EDT