Reefs Worldwide Are Slowly Moving Poleward as Oceans Warm

Global reef systems are slowly migrating poleward as oceans around the world continue to warm as a result of human-driven global warming, a new study says.

British researchers used fossil records and simulation models to analyze the state of the world's reefs, including Australia's Great Barrier Reef, the largest living structure on Earth.

The team of scientists from several British universities discovered a pattern of decline along the equatorial side of the reefs and growth along the polar sides of reefs, according to the research published last week in the Royal Society Open Science.

The researchers noted that the migration is not a recent phenomenon but likely has occurred over hundreds if not thousands of years, the Sydney Morning Herald reported.

“It should also be (kept) in mind that reef corals, and coral reef ecosystems, are far less likely to survive other stressors, such as overfishing and pollution, when residing in marginal habitats,” the researchers wrote.

“Furthermore, our projections … may be relatively optimistic in the face of anthropogenic climate change as they do not account for the impacts of ocean acidification.”

Still, the researchers say the findings could be useful in predicting what will happen to reefs worldwide as global warming accelerates.

In a separate study published last week in the Proceedings of the Royal Society B, researchers used satellite images from Google Earth to analyze where fish are eating along the global reef systems, which helps estimate the health of sea life and detect and predict changes to reefs worldwide.

“This approach demonstrates that we can now detect aspects of reefs’ ecological responses to protection, even in remote and inaccessible reefs globally,” the researchers wrote.

“To quantify effectiveness of the world’s marine reserves, we must look beyond current methods to more scalable, cost-effective approaches, of which satellite-based observation of the world’s reefs may be one.”

In Australia, the government has committed $500 million to help save the Great Barrier Reef, including $40 million that goes toward health monitoring, the Tech Times reported.

Australian scientists have also deployed sun shields to protect the reef system.

In 2017, UNESCO's World Heritage Committee said the reef that was listed on the UNESCO list in 1981 is not "in danger" despite mounting evidence that the back-to-back coral bleaching events in 2016 and 2017 threatened the survival of the site. There has not been an update on state of the site since 2017.

To be listed "in danger" by UNESCO, a natural site must show a "serious decline in the population of the endangered species" or "severe deterioration of the natural beauty or scientific value of the property," among other things.