The Great Barrier Reef is one of the seven natural wonders of the world, home to an incredible diversity of sea life. It's the largest coral reef in the world, covering more than 345,000 square kilometers.
But lately, the reef is losing more and more of its living outer layer. That's according to recent research in Proceedings of the National Academy of Sciences.
Looking back to 1985, scientists found that the number of living polyps has declined from more than 25 percent of the reef's surface to just under 14 percent. Most of that loss has come in the last decade or so in areas where humans live closest to the reef.
The problem is the number of challenges facing the reef. There's coral bleaching due to the hot temperatures induced by human-caused climate change. There's our sewage and agricultural runoff flowing into the sea. There are even outbreaks of coral-chomping starfish, aided and abetted by human activity.
Not all is lost. The relatively pristine northern end of the reef shows that coral could recover, given the chance. For that to happen, we all will have to do more to combat climate change.
[The above text is a transcript of this podcast.]