Warm waters fueled by El Niño are threatening to kill Hawaiian coral through a process called coral bleaching, according to researchers from the National Oceanic and Atmospheric Administration.
The process occurs when warm water triggers the expulsion of zooxanthellae algae that lives in coral the tissues, which in turn “bleach” the coral white. NOAA researchers explain that while the bleaching process itself does not always kill the coral, it makes them significantly more vulnerable to death in other ways, such as disease.
In Hawaii, NOAA researchers have predicted this for some time. Warm water temperatures off the coast of Hawaii triggered a bleaching incident last year, from which the surviving corals have yet to still fully recover from.
The area also experienced a “major bleaching event” in Hawaii nine years ago, according an Associated Press report.
Researchers are worried that if the developing El Niño warms waters further, the coral bleaching this year could be the worst Hawaii has ever seen.
Many native aquatic species that live in the Hawaiian waters depend on the coral to survive. If the coral dies off, fish and other sea creatures will likely be put at risk as well.
Another major concern is that the death of marine life could mean the death of tourism, since many Hawaiian tourists visit the island to explore the realm underneath the waves.
Ruth Gates, the Hawaii Institute of Marine Biology director, described the potential impact in an analogy that suggests the death of the coral would make the waters as attractive as an abandoned underwater parking lot. “You go from a vibrant, three-dimensional structure teeming with life, teeming with color, to a flat pavement that’s covered with brown or green algae,” she explained.
You go from a vibrant, three-dimensional structure teeming with life, teeming with color, to a flat pavement that’s covered with brown or green algae. That is a really doom-and-gloom outcome but that is the reality that we face with extremely severe bleaching events.
The National Weather Service in Honolulu reported that the Hawaiian water temperatures are approximately 3º to 6º Fahrenheit above normal.
Half of the coral reefs in the Caribbean were killed following a massive bleaching near Puerto Rico and the Virgin Islands in 2005 that was triggered by unusually warm waters.
The bleaching process can also occur if the water temperature gets too cold. NOAA referenced a situation that occurred in January of 2010 where a 12º Fahrenheit water temperature drop around the Florida Keys triggered a coral bleaching event that killed off some of the region’s coral.
Though rapid swings in temperature to anomalous levels can trigger fatal coral bleaching, scientists have noticed that some coral can adapt to climate change.
