Scientists have sounded the alarm over the disappearance of the Great Barrier Reef after discovering a starling.
They found that ocean temperatures around this natural wonder are now the highest they have been in at least 400 years, reaching 0.34 degrees Fahrenheit above the previous record.
Researchers have warned that if warming continues, the iconic ecosystem could disappear within the next 30 years.
The findings were made by drilling coral cores to identify geochemical changes and reconstruct past sea surface temperatures.
An aerial photograph shows bleached and dead corals around Lizard Island on the Great Barrier Reef, April 4, 2024. Researchers have warned that if warming continues, the iconic ecosystem could disappear within the next 30 years.
“If humanity does not deviate from its current course, our generation will likely witness the demise of one of Earth’s great natural wonders,” wrote Benjamin Henley, lead author of the study at the University of Melbourne. The conversation.
The research team, comprised of several Australian universities, analysed long-lived corals in and around the reef.
These corals hold a record of ocean temperatures in their skeletons, which the researchers used to reconstruct sea surface temperatures from 1618 to 1995, along with modern sea surface temperature measurements spanning from 1900 to 2024.
Co-author Helen McGregor said it was like counting the rings of a tree to determine its age.
Their research found that Coral Sea surface temperatures remained relatively stable and cool for centuries before rapid increases to record levels occurred between January and March, posing a threat to the reef.
The analysis revealed that ocean temperatures around the reef have increased significantly since 1960, with five of the six warmest years on record occurring in the past decade.
‘Between 1960 and 2024, we observe an average annual summer warming of 0.216°F per decade,’ the researchers share in The Conversation.
They found that ocean temperatures around the natural wonder are now the highest in at least 400 years, reaching 0.34 degrees Fahrenheit above the previous record.
The research team drilled cores of coral skeletons on the Great Barrier Reef to create a record of climate data.
Researchers linked this temperature increase to man-made climate change.
“The Great Barrier Reef is in danger right now,” Henley told DailyMail.com.
‘Serious episodes of mass bleaching are likely to occur in the coming years.’
Scientists have long said that further coral loss is likely a casualty of future warming as the world approaches the 2.7°F threshold that countries agreed to try to keep warming below in the 2015 Paris climate agreement.
Even if global warming remains below the Paris Agreement target, which scientists say Earth will almost certainly exceed, 70 to 90 percent of the world’s corals could be threatened, the study’s authors said.
Australia’s Great Barrier Reef is the world’s largest coral reef system, covering an area of 345,000 square kilometres (an area larger than Italy) off the coast of Queensland. It is so large that it is visible from space.
The Great Barrier Reef attracts more than two million tourists each year.
Rising ocean temperatures are causing massive coral bleaching events on the Great Barrier Reef
This biodiversity hotspot is home to more than 9,000 known species, including 400 types of coral, 1,500 species of fish and 4,000 types of molluscs.
It also supports tourism, fishing and other commercial industries. The reef’s total economic value is estimated at $56 billion and supports approximately 64,000 jobs.
But that could soon change, scientists warn.
When ocean temperatures get too high, corals expel the algae that live in their tissues.
This process, known as coral bleaching, turns corals completely white, deprives them of their main food source and makes them more vulnerable to disease.
Corals can survive bleaching, but they need time to recover, Henley said. He worries that the frequency of mass bleaching events could increase as ocean temperatures continue to rise.
If even one mass bleaching event occurred per year, it would be extremely difficult for corals to recover, putting them at greater risk of death.
This summer, the Great Barrier Reef suffered the most extensive and extreme mass bleaching event on record, scientists from the Australian Institute of Marine Science said in a separate report released this week.
It was the fifth mass bleaching event on the reef in just eight years.
This study offers new insight into how rising ocean temperatures have affected the Great Barrier Reef over the long term and will continue to affect it in the future, Henley said.
As climate change progresses, its effects on the Great Barrier Reef will be felt both locally and internationally, and in terms of environmental and economic impacts.
“It’s a place of spectacular beauty and ecologically unique,” Henley said, adding: “It’s a very special place and we’re losing it.”
