Where to admire coral atolls, the sapphires of the sea
Spectacular in their beauty, they remain threatened by climate change
Did you know that the Maldives is the largest coral atoll in the world? A coral atoll is a ring-shaped coral reef or island that surrounds a lagoon, and this Indian Ocean archipelago boasts 26 of them. And did you also know that Huvadhu Atoll, anchored south of the Maldives, is the largest atoll in the world in terms of island numbers, with 255 lying scattered across an area of 1,216 sq mi (3,152 sq km)?
Atolls develop with underwater volcanoes, called seamounts. If a fringing reef forms around a volcanic island that erodes or subsides while the coral continues to grow upward, an atoll is created. The lagoon forms over the volcanic crater or caldera.
While the Maldives is arguably the best-known coral atoll (not least because of its status as one of the world's most exotic resort and diving destinations), there are literally thousands of these natural wonders dotted across the Indian and Pacific oceans. Eight atolls are found in the Caribbean Sea. The Atlantic Ocean, however, has no large group of atolls. Indeed, they are only found in the tropics and subtropics.
From the air, atolls resemble sapphires sprinkled on blankets of turquoise velvet. But the most rewarding way of exploring these extraordinary geological gems is by diving among the colorful and visually stunning reefs lying just below the water's surface. These fascinating marine ecosystems teem with tropical sea life, which thrive in some of the cleanest environments on the planet. Many atolls are designated UNESCO World Heritage Sites, recognized for their enchanting beauty and amazing biodiversity.
But these fragile marine reserves are under threat from global warming and the plastic waste epidemic.
The risk posed by rising sea levels is a credible one. If the issue of climate change is not addressed with the conviction it deserves, thousands of islands from the Maldives to Hawaii could become uninhabitable within decades. Similarly, the Great Pacific Garbage Patch is a collection of plastic and floating trash that research indicates is rapidly expanding.
But back to atolls and their beautiy—click through this gallery for an engaging journey to some of the most captivating atolls on the planet.
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