National Geographic : 2018 Aug
N 81 1 1 Townsville Cairns Cooktown Lockhart River Mackay AUSTRALIA CapeYork Peninsula NEW GUINEA NEW GUINEA MARINEPARKGR E ATBARRIERREEFGREATBARR IER REEF GREAT BAR R I ERREEF T orresStraitEndeavourStr. S helburneBay Gulf of Carpentaria Co ralSea Gulf of Papua Palm Is. Saibai Island Prince of Wales Island Osprey Reef Flinders Reefs Holmes Reefs Ashmore Reef Portlock Reefs Eastern Fields Coringa Bank Tregrosse Reefs Marion Reef Lihou Reefs Swain Reefs Whitsunday Group Cape York CapeGren ville F air Cape Cape Melville CapeFlatter y F AR NO RT HE R NM A N AG EMEN TAR E A EXPLORE | ATLAS ILLUMINATING THE MYSTERIES—AND WONDERS—ALL AROUND US EVERY DAY NATIONAL GEOGRAPHIC VOL. 234 NO. 2 EXPLORE IN THIS SECTION Hidden Afghanistan Toxic Sulfur Mine Starving Polar Bear Reef bleaching severity Proportion of individual reef in 1998, 2002, or 2016 event* Extreme (more than 60%) Moderate (30–60%) Low (10–29%) HALF OF THE GREAT BARRIER REEF has been bleached to death since 2016. Mass coral bleaching, a global problem triggered by climate change, occurs when unnaturally hot ocean water destroys a reef ’s colorful algae, leaving the coral to starve. The Great Barrier Reef illustrates how extensive the damage can be: Thirty percent of the coral perished in 2016, another 20 percent in 2017. The effect is akin to a forest after a devastating fire. Much of the marine ecosystem along the reef ’s north coast has become barren and skeletal with little hope of recovery. CORAL CRISIS SCALE VARIES IN THIS PERSPECTIVE. DISTANCE FROM SAIBAI ISLAND TO CAPE YORK IS 90 MILES. *MOST SEVERE SCORE (SOME REEFS SURVEYED IN MORE THAN ONE BLEACHING). TERRAIN RENDERING: CHARLES PREPPERNAU. ART: MATTHEW TWOMBLY. SOURCES: ARC CENTRE OF EXCELLENCE FOR CORAL REEF STUDIES; NOAA CORAL Worse than expected Bleaching in 2016 occurred so rapidly that scientists had to retool their predic- tions for how much heat the reef could endure.