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Coral reef is suffering
The Great Barrier Reef(大堡礁) in Australia, the world's largest coral(珊瑚) reef system and home to many kinds of sea animals, is in great danger. It is now experiencing its third mass bleaching(白化) in five years, resulting in the death of large amounts of coral.
"We know this is a mass bleaching event and it's a serious one," Professor Terry Hughes told the Guardian. Professor Terry Hughes, one of the world's leading experts on the reef, said it is far more serious than former mass bleaching events. It is a clear signal(信号) for people to take action.
Coral bleaching refers to the death of coral caused by high water temperatures. Global warming has caused ocean temperatures to rise, resulting in more frequent bleaching events. Many tropical(热带的) coral reefs will disappear if temperatures continue to rise, according to the UN's Intergovernmental Panel on Climate Change.
As more of the Great Barrier Reef bleaches and dies, the animals that depend on it will die off as well. About 500 million people depend on the reef and the animals there to make a living, according to the International Union for Conservation of Nature.
The ocean fishing industry, for example, depends on fish living in the Great Barrier Reef, as well as other reefs around the world. Reefs also protect coastlines from the damaging(有破坏性的) effects of tropical storms, as well as promote(促进) tourism, according to the Queensland Museum. Humans will be heavily influenced by their disappearance.