Bleaching of corals worldwide

Coral reefs around the world are experiencing global bleaching for the fourth time - a result of warming ocean waters - driven in part, by climate change.

Bleached coral near the Keppel Islands in the Great Barrier Reef, Australia (AP Photo/Ove Hoegh-Guldberg) Source: AP

This is the fourth global, mass coral bleaching, according to the U.S. National Oceanic and Atmospheric Administration. Corals rot and die when sea conditions are not favorable for their

existence. The reason for the bleaching: rising ocean temperatures;

corals, a vital marine organism, are affected by sea temperature.

The phenomenon has affected coral reefs in every major ocean basin. The reefs are

home to about a quarter of all marine life. The

news filled scientists and ecologists around the world with sadness. The

bleaching event also affected the Great Coral Reef Australian. Lissa Schindler, a thallasian ecologist, has been monitoring the Great Coral Reef for the past 20 years. Describing the image she saw on her recent trip to the Reef, she said it was the first time she had gone to diving and I didn't want him to get back in the water. “I've never felt so sad before,” she said.

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