The turquoise underwater world off the coast of Australia is one of the world’s great natural wonders: a colorful underwater forest teeming with life that scientists say shows some of the clearest signs yet of climate change.
Battered but not broken by the effects of climate change, the Great Barrier Reef inspires hope and concern as researchers try to understand how it might survive a warming world. Officials try to buy time for the reef by combining old knowledge with new technology. They are studying the breeding of coral in hopes of accelerating its growth and adapting it so that it can survive in warmer and harsher seas.
Underwater heat waves and cyclones caused by fugitive greenhouse gas emissions have devastated some of the 3,000 reefs that make up the Great Barrier Reef. Pollution fouls its waters and outbreaks of a species of starfish known as the crown of thorns have destroyed its coral.
Researchers say climate change is already threatening the vibrant marine infrastructure and everything that depends on it, and they warn that more destruction is yet to come.
“It’s a clear sign of climate change. It’s going to happen again and again,” said Anne Hoggett, director of the Lizard Island Research Station, of the reef’s continued damage from storms and more severe oceanic heat waves. “It’s going to be a roller coaster.”
Billions of microscopic animals called polyps formed this amazing 1,400-mile-long (2,240-kilometer) colossus that is perhaps a million years old and visible from space. It is home to thousands of species of plants and animals, and supports a tourism industry worth $6.4 billion annually.
“Corals are engineers. They create shelter and food for countless animals,” said Mike Emslie, head of the Long Term Monitoring Program for Reefs at the Australian Institute of Marine Sciences (AIMS).
During their 37 years of underwater assessments, the Emslie team has seen disasters multiply and strike with greater frequency.
Heat waves in recent years have caused the corals to expel myriad tiny organisms that feed on the reef through photosynthesis, causing the branches to lose their color and “bleach”. Without those algae, corals don’t grow, can become brittle and provide little support for the nearly 9,000 species that depend on the reef. Cyclones in the past decade have destroyed acres of coral. Each of these was a historic catastrophe in itself, and because there was no time to recover between each of those events, the rock was unable to grow again.
However, the Emslie team observed new corals that germinated more quickly than expected.
“The rock is not dead,” he declared. “It is an amazing, beautiful, complex, remarkable system that has the potential to recover if given the chance and the best way for us to give it the chance is to reduce carbon emissions.”
The first step in the government’s plan to restore the reef is to better understand the coral’s enigmatic life cycle.
To do this, dozens of Australian researchers go out to sea along the reef when conditions are favorable for their reproduction, during a spawning event that is the only time of year when coral polyps breed naturally when winter is warm and turns into spring.
But scientists say reproduction rates are too slow for corals to survive global warming. That’s why they wear scuba gear to collect eggs and sperm coral during spawning. Back in their labs, they test ways to speed up the coral’s reproductive cycle and stimulate genes that help them survive high temperatures.
One such laboratory, on a yacht converted into a scientific yacht, floats off the coast of Konomi Island, also known as North Keppel Island, a two-hour boat ride from the Queensland mainland.
On a recent overcast afternoon, Carly Randall, who directs AIMS’s Coral Restoration Program, stood among buckets filled with coral specimens and experimental coral planting techniques. He explained that the long-term plan is to cultivate “tens to hundreds of millions” of baby corals each year and plant them along the reef.
Randall compared the effort to planting trees using drones, but underwater.
His colleagues at AIMS have successfully grown corals in the lab in the off-season, an important first step in possibly introducing genetic adaptations on a large scale, such as allowing them to be more resistant to heat.
Engineers design the robot to fit onto a mother ship that will deploy the underwater drone. Those drones would attach genetically selected corals to the reef with boomerang-shaped clips. Targeting corals would enhance the reef’s “natural recovery process”, which would eventually “over and above the work we are doing to sustain it during climate change”.
Australia has recently been hit by record wildfires, floods and cyclones due to climate instability.
Bill Hare, CEO of the firm Climate Analytics, said it has spurred a political shift in the country as voters become more concerned about climate change, helping to drive a change in national leadership during federal elections this year. .
The country’s previous prime minister, Scott Morrison, was a Conservative who has been criticized for downplaying the need to tackle climate change.
The new centre-left government of Anthony Albanese has passed a law to reach net zero carbon emissions by 2050, which includes a 43% reduction in greenhouse gas emissions by 2030. Australia is one of the world’s largest exporters of coal and liquefied natural gas and lags behind the emissions targets of major industrialized nations.
The new government has blocked the opening of a coal plant near the Great Barrier Reef, but has recently granted new permits to other coal plants.
It continues to invest in boosting the reef’s natural ability to adapt to a rapidly warming climate.
The Great Barrier Reef, the size of Italy, is managed as a national park by the Great Barrier Reef Marine Park Authority (GBRMPA).
GBRMPA chief scientist David Wachenfeld said that “despite the recent effects of climate change, the Great Barrier Reef is still a vast, diverse, beautiful and resilient ecosystem.”
Yet it is today, in a world that has warmed by about 1.1 °C (2 °F).
“As we approach 2 degrees (Celsius) and certainly as we exceed it, we will lose the world’s coral reefs and all the benefits they provide to humanity,” Wachenfeld warned. As home to more than 30% of marine biodiversity, coral reefs are essential to the livelihoods of hundreds of millions of people in the tropics, he said.
The Great Barrier Reef is “part of the national identity of Australians and has spiritual and cultural significance for First Nations people,” Wachenfeld said.
After much abuse and neglect by the federal government, Aboriginal groups now have an increasing role in the management of the reef. The government requests your permission for projects there and contracts with the communities to study and resolve it.
Many members of the Yirganadji and Gunggandji communities work as guides, marine park rangers and researchers in reef conservation and restoration projects.
After diving into turquoise waters teeming with fish and vibrant coral, Tarquin Singleton said his people have memories of this “sea country” that date back more than 60,000 years, including past climate changes.
“This connection is ingrained in our DNA,” said Singleton, who is originally from the Yirgandji people from the area around the Australian city of Cairns. He now works as a cultural officer with tourism agencies and the Reef Cooperative, a joint venture between the government and Aboriginal groups.
“Using it today can really preserve what we have for future generations,” he said.
The Woppabura people, the original inhabitants of the Konomi and Woppa islands, barely survived colonization by Australia. Bob Muir, an Indigenous elder who works as a community liaison with AIMS, said he is now creating a new kind of unity by sharing ancient oral histories and working on research vessels “in a way that normally would not be” Used to be.
Right now, growing and planting coral throughout the reef is science fiction that seems possible. Randall said it is currently too expensive to scale it to the levels needed to “buy reef time” while humanity cuts emissions.
He expressed hope that within 10 to 15 years, drones could already be on the water.
However, Randall warns that robots, coral farms and expert divers “will not work at all if we don’t first control emissions.”
“This is one of many tools in the box being developed,” he said. “But unless we can get emissions under control, we don’t have much hope for the reef ecosystem.”