Northern Red Sea Could Be Unique Global Warming Refuge for Coral
Scientists from the King Abdullah University of Science and Technology (KAUST), the University of Essex and Al-Azhar University believe that a stretch of nearly 1,120 miles could become one of the few—and one of the largest—refuges for coral.
By 2040, 25 out 29 World Heritage reef areas will experience twice-per-decade bleaching, an occurrence that will "rapidly kill most corals present and prevent successful reproduction necessary for recovery of corals," the United Nations Educational, Scientific and Cultural Organization concluded. In the past three years alone, three-fourths of the world's reefs have experienced severe bleaching.
Since the Gulf of Aqaba lies at the northern edge of the Red Sea, the surface water temperature is coolest. Uniquely, coral in the entire Red Sea is heat resistant, but populations in the south are already nearing their tipping point. "Bleaching usually occurs at 1°C over the summer mean average temperature," Christian Voolstra, one of the study's authors, told Nature Asia. In the northern waters of the Gulf of Aqaba, coral enjoys a temperature margin of 5°C.
To reach these conclusions, scientists compared patterns of coral heat sensitivity across the Red Sea to a dataset of coral bleaching events since 1982. This allowed them to identify areas least susceptible to thermal stress. The team then looked at thermal histories of Hurghada, Egypt and Thuwal, Saudi Arabia—each bordering the Red Sea—and their coral-bleaching patterns, but also the effect of 2015-2016 El Niño events on their coral areas. From this they were able to conclude that the Red Sea's northern coral was less susceptible to rises in water temperature.
"This anomaly, which is only found in the Red Sea, gives us a window of opportunity to take action," Voolstra said.
But tucked between Egypt, Jordan, Israel and Saudi Arabia, the coral will also have to contend with local, human-made threats, such as pollution and coastal development.
The Gulf of Aqaba is home to two bustling port cities, the Israeli city of Eilat and the Jordanian city of Aqaba, both sitting next to coral reefs. In 2016, 200 tons of crude oil spilled into the gulf after an oil pipeline burst in the port of Aqaba.
To the south of Aqaba and Eilat, Saudi Arabia and Egypt are planning a massive bridge to link the two countries. Such a project could disturb the fragile ecosystem.