| Summary: | The biodiversity crisis, explained More than five years ago, the world’s top climate scientists made a frightening prediction: If the planet warms by 1.5 degrees Celsius, relative to preindustrial times, 70 to 90 percent of coral reefs globally would die off. At 2°C, that number jumps to more than 99 percent. In not so great news, the planet is now approaching that 1.5°C mark. In 2023, the hottest year ever measured, the average global temperature was 1.52°C above the preindustrial average, as my colleague Umair Irfan reported. That doesn’t mean Earth has officially blown past this important threshold - typically, scientists measure these sorts of averages over decades, not years - but it’s a sign that we’re getting close. So, it’s no surprise that coral reefs are, indeed, collapsing. Earlier this month, the National Oceanic and Atmospheric Administration (NOAA) announced that the planet is experiencing its fourth global “bleaching” event on record. Since early 2023, an enormous amount of coral in the Pacific, Atlantic, and Indian oceans has turned ghostly white, including in places like the Great Barrier Reef and the Florida Keys. In some regions, a lot of the coral has already died. “What we are seeing now is essentially what scientists have been predicting was going to happen for more than 25 years,” Derek Manzello, a marine scientist at NOAA who leads the agency’s coral bleaching project, told Vox. The recent extreme ocean warming can’t solely be attributed to climate change, Manzello added; El Niño and even a volcanic eruption have supercharged temperatures. But coral reefs were collapsing well before the current bleaching crisis. A study published in 2021 estimated that coral “has declined by half” since the mid-20th century. In some places, like the Florida Keys, nearly 90 percent of the live corals have been lost. Past bleaching events are one source of destruction, as are other threats linked to climate change, including... |