Coral reefs in Hawaii could suffer a devastating impact from a major marine heat wave in the Pacific, scientists say. Earlier this month, scientists said that the heat wave is the second-largest heat wave recorded in the Pacific Ocean. June, July, and parts of August all experienced the hottest ocean temperatures ever recorded around the Hawaiian Islands. So far in September, marine temperatures are below only those seen in 2015.
Federal researchers are predicting that the hot water will cause some of the worst coral bleachings the region has ever experienced. Coral bleaching happens when corals are stressed by changing ocean conditions, as they are vulnerable to even minor increases in temperature. They expel the algae living in their tissues, which causes them to turn completely white. If the loss of algae continues for a prolonged period of time, the coral will eventually die.
The coral reefs along the coastline of Papa Bay near Hawaii’s Big Island have the highest risk. A catastrophic event in 2015 killed nearly half of the coral along this part of Hawaii’s coastline, according to Hawaii’s Division of Land and Natural Resources. Because the corals are still recovering from the damage they suffered then, the current heat wave could be even more dangerous.
Just about every region of the world has been breaking temperature records these days. The impact stretches from north of Bermuda, through the Bahamas, and all the way to Honduras. The heat that would ordinarily go into the atmosphere has been absorbed into the upper ocean. According to the National Oceanic and Atmospheric Administration (NOAA), the Pacific heat wave is only beginning. Climate models show that the warmer waters may continue through November.
The NOAA has released a 2019 coral bleaching alert with recommendations for locals and tourists. These recommendations include keeping anchors away from reefs, disposing of chemicals like fertilizers and oils properly, and standing on sand instead of the reef. It also recommends giving the corals and fish some space and avoiding killing parrotfish, surgeonfish and other herbivores that eat the algae that can cover and kill corals.