Australia has criticized a United Nations plan to declare the country’s Great Barrier Reef “in danger” from climate change. The U.N.’s Educational, Scientific and Cultural Organization (UNESCO) proposed this week that the Great Barrier Reef be added to its List of World Heritage in Danger. A UNESCO committee report said this week it had found that “there is no possible doubt” that the reef’s collection of colorful corals was “facing ascertained danger.” The Great Barrier Reef covers about 344,000 square kilometers of area on Australia’s northeast coast. It contains about 3,000 reefs, natural structures made by very small animals called corals. The reef also includes more than 900 islands. The reef has been listed as a World Heritage site since 1981. A report by the committee said it found the Great Barrier Reef had suffered major coral bleaching events in 2016, 2017 and 2020. It blamed the events on unusually warm ocean temperatures. UNESCO said the “in danger” listing was needed to make sure action is taken to protect the reef from the effects of climate change. Such “corrective measures” would likely include stronger rules to reduce pollution linked to greenhouse gases. Adding the reef to UNESCO’s “in danger” list could also reduce the number of international visitors coming to the area to see the huge collection of colorful corals.