Australia’s Great Barrier Reef hit by fifth mass bleaching event in eight years

Trending 2 months ago

Australia’s Great Barrier Reef is experiencing yet different wide coral bleaching event owed to heat, nan country’s authorities confirmed Friday.

The Great Barrier Reef Marine Park Authority, which oversees efforts to sphere and protect nan reef, said a wide bleaching arena is unfolding that is “consistent pinch patterns of power accent that has built up complete summer.”

Scientists pinch nan Australian Institute of Marine Science said this is nan fifth wide bleaching arena to deed nan Great Barrier Reef since 2016. 

Bleaching events are a major threat to nan wellness of coral reefs astir nan world. Coral bleaching occurs arsenic a consequence of abnormal conditions, specified arsenic erstwhile water temperatures are unusually lukewarm aliases cold, aliases erstwhile water h2o is much acidic than normal. In response, corals expel mini photosynthetic algae that unrecorded successful their tissues, causing nan usually colorful marine invertebrates to move white.

Bleaching does not needfully termination corals, but nan process causes reefs to go much susceptible to disease. Corals tin retrieve from wide bleaching events, but erstwhile they hap frequently, scientists person said it is harder for reefs to bounce back.

Studies person shown that ambiance alteration is elevating water temperatures astir nan world, making coral bleaching events much frequent. Last year, global oversea aboveground temperatures shattered records, spiking arsenic aggregate bodies of h2o knowledgeable “unprecedented” and long-lasting marine power waves.

El Niño conditions were besides a facet successful 2023, compounding inheritance warming from ambiance change. El Niño, a earthy ambiance rhythm characterized by warmer-than-usual waters successful nan Pacific Ocean, typically increases mean aerial and oversea temperatures and tin person a important effect connected rainfall, hurricanes and different terrible weather.

Researchers observe a wide coral bleaching arena astatine a tract successful nan Southern Great Barrier Reef connected March 5.Researchers observe a wide coral bleaching arena astatine a tract successful nan Southern Great Barrier Reef connected March 5.Renata Ferrari / Australian Institute of Marine Science

The Great Barrier Reef Marine Park Authority said nan existent wide bleaching arena is accordant pinch akin reports of bleaching crossed Northern Hemisphere reefs arsenic a consequence of El Niño conditions successful nan Pacific Ocean and elevated water temperatures exacerbated by ambiance change.

Together pinch scientists astatine nan Australian Institute of Marine Science, nan agency conducted aerial surveys that covered astir two-thirds of nan Great Barrier Reef Marine Park. These observations included much than 300 inshore, midshelf and offshore reefs, successful nan confederate and cardinal regions, according to nan scientists.

While nan groups were capable to corroborate that a wide bleaching arena is underway, further study and in-water assessments are required to understand its severity and imaginable impacts.

Researchers are expected to behaviour further aerial surveys complete different parts of nan reef erstwhile upwind conditions are suitable.

So far, nan researchers noted that power accent does not look moreover crossed nan reef.

“As nan Great Barrier Reef ecosystem is truthful large, nan size of Italy, nan power accent crossed it isn’t uniform,” Neal Cantin, a elder investigation intelligence astatine nan Australian Institute of Marine Science, said successful a statement. “As a result, we are seeing differences betwixt reefs pinch respect to nan number of corals that are wholly white.”

Coral bleaching affects a coral, left, astatine Arlington Reef, Central Barrier Reef, connected Feb. 27. Coral bleaching affects a coral, left, astatine Arlington Reef, Central Barrier Reef, connected Feb. 27. Grace Frank / Australian Institute of Marine Science

The first recorded bleaching arena astatine nan Great Barrier Reef occurred successful 1998, and a 2nd was observed successful 2002. After a 14-year gap, 4 others occurred successful adjacent succession: successful 2016, 2017, 2020 and 2022.

Prior to these events, location was nary different grounds of wide bleaching events successful nan Great Barrier Reef’s 500-year coral record-keeping history, according to nan Australian Institute of Marine Science.

Officials said nan results of aerial surveys and in-water observations will thief authorities agencies understand conditions crossed nan reef and really champion to negociate restoration efforts.

But David Wachenfeld, a investigation programme head astatine nan Australian Institute of Marine Science, said that protecting nan Great Barrier Reef will require addressing its biggest threat: ambiance change.

“[T]o protect coral reefs for illustration nan Great Barrier Reef from ambiance change, we request beardown world emissions simplification to stabilise temperatures, champion believe guidance of section issues, and nan investigation and improvement of interventions to thief boost ambiance tolerance and resilience for coral reefs,” he said successful a statement.


Denise Chow

Denise Chow is simply a newsman for NBC News Science focused connected wide subject and ambiance change.