Scientists are sounding the alarm after learning that the world is currently undergoing its fourth global coral bleaching event.
A team of global reef scientists from the National Oceanic and Atmospheric Administration (NOAA) announced the concerning news on Monday. The bleached reefs are caused by abnormally high ocean temperatures across the Atlantic, Pacific, and Indian Oceans. It is the second such occurrence in the last decade, sparking calls for global action.
Bleaching occurs when water becomes too warm, causing the coral reefs to expel the algae living in their tissues. Although bleached coral reefs can recover, the stress causing the bleaching must diminish before recovery can happen.
According to an NOAA press release, mass bleaching has been identified in at least 53 countries over the past year.
"As the world's oceans continue to warm, coral bleaching is becoming more frequent and severe," NOAA Coral Reef Watch Coordinator Derek Manzello said in the release. "When these events are sufficiently severe or prolonged, they can cause coral mortality, which can negatively impact the goods and services coral reefs provide that people depend on for their livelihoods."
Manzello told Newsweek that "coral reefs are the rainforests of the sea and represent the most biodiverse ecosystem in the oceans."
"It is estimated that roughly 25 percent of all marine species associate with coral reefs at some point in their lives," Manzello said. "Thus, the large-scale death of corals and degradation of coral reefs threatens the survival of 1 in 4 of every living organism in the ocean!"
The bleached coral reefs are prompting widespread concern among marine experts. Ove Hoegh-Guldberg, a professor of marine studies at the University of Queensland, told The New York Times that the knowledge can make him feel depressed.
"Now we're at the point where we're in the disaster movie," he said of the bleached reefs in the report.
Manzello told Newsweek that bleaching previously occurred in 1998, 2010, and then for three years from 2014 to 2017. The worst bleaching event was the latter period, in which 56 percent of the world's reefs were bleached.
More than 54 percent of the world's reefs are bleached so far this year. The current bleaching is expected to surpass that from 2014 to 2017 because the reefs experiencing high heat stress are increasing by 1 percent per week, Manzello said.
However, Manzello said that the end of El Niño is a "nugget of hope." Forecasts anticipate the end of El Niño this summer, and La Niña is expected to begin this fall.
El Niño and La Niña are two climate patterns that greatly impact Earth's weather. La Niña recently culminated last spring, ending a multiyear period in which the pattern influenced the weather. El Niño is characterized by warmer ocean waters.
Warm ocean temperatures are impacting the environment in other ways, as well.
Earlier this month, Colorado State University meteorologists predicted an "extremely active" Atlantic hurricane season, citing abnormally warm ocean temperatures as one reason.
Meteorologists predicted 23 named storms in 2024, 11 hurricanes, and five major hurricanes. This is the highest number of hurricanes predicted in the 41-year history of publishing the outlooks in April.
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Newsweek is committed to challenging conventional wisdom and finding connections in the search for common ground.
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Anna Skinner is a Newsweek senior reporter based in Indianapolis. Her focus is reporting on the climate, environment and weather ... Read more
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