Science official: Ocean acidity major reef threat

The head of a U.S. scientific agency says ocean acidification is now one of the biggest threats to coral reefs across the world, acting as the "osteoporosis of the sea."

National Oceanic and Atmospheric Administration chief Jane Lubchenco told The Associated Press on Monday that the speed by which the oceans' acid levels has risen surprised scientists. She says the problem could threaten everything from food supplies to tourism to livelihoods.

Oceans absorb excess carbon dioxide in the atmosphere, leading to an increase in acidity. Scientists are worried about how that increase will affect sea life, particularly reefs, as higher acid levels make it tough for coral skeletons to form.

Lubchenco is in Australia to speak at the International Coral Reef Symposium in Cairns, near the Great Barrier Reef.