Photo: Courtesy of the ARC Centre of Excellence for Coral Reef Studies

Oh dear, this is bad

Last year at the International Coral Reef Symposium in Honolulu, many of the gathered researchers and scientists shared moments of mourning, some openly shedding tears.

The symposium is held every four years, and this time it had brought the world’s foremost coral experts together in a time of crisis. The Great Barrier Reef, and other coral systems around the world, were experiencing some of the worst coral bleachings ever recorded.

Now, a year later, the situation has grown even more dire. 2017 brought another wave of bleaching, and scientists fear some reefs, thanks to a rise in average ocean temperatures, will never recover.

Warmer seas and widespread bleaching have affected reefs around the world, but none has garnered as much attention as the granddaddy of them all: the Great Barrier Reef. A hotbed of life visible from space, the Great Barrier Reef was named a UNESCO world heritage site in 1981. In June, the organization declined to declare the reef “in danger,” which would have unlocked additional funding and resources for protecting the marine resource.

Yet, coral experts are on record saying the Great Barrier Reef and many others will never fully recover from recent events. New research from the National Oceanic and Atmospheric Association indicates more than two-thirds of the world’s coral reefs were hit by bleaching in the multi-year event. In the United States, reefs in the waters off of Hawaii, Florida, Guam and Puerto Rico are at risk of severe bleaching as ocean temperatures rise, and could die off in a matter of years if the current trend continues.

With more scientists sounding the alarm, let’s examine the chief threats facing the world’s reefs—and the implications of their demise.

What is coral bleaching?

Bleaching is a process that saps corals of their vibrant colors and can eventually lead to death. Corals get their hues from photosynthetic algae, called zooxanthellae, that live inside them. As sea temperatures rise, the algae are expelled from the coral, which turn translucent and white. Coral can recover if temperatures return to normal quickly enough, but prolonged stress may kill whole sections of reef.

A plane and its crew conduct an aerial survey of bleaching on the Great Barrier Reef. Courtesy of the ARC Centre of Excellence for Coral Reef Studies

Haven’t reefs rebounded from this kind of thing before?

Yes. However, prior to recent history, bleaching events were more spread out and reefs generally had longer to heal. Now, some regions have experienced bleaching three years in a row, and the events are lasting longer and causing more damage than before.

Why is bleaching suddenly more of a threat?

The average surface temperature of the Earth’s oceans, which absorb 90 percent of the excess heat generated from the human-related release of greenhouse gases, has risen 1 degree Celsius since 1910. Natural climatic events, like the 2015-’16 El Niño, periodically contribute to warmer sea temperatures and push conditions even farther past the comfort zone for coral.

Since 2014, a global coral bleaching event has moved with the seasons between the northern and southern hemispheres, affecting around 70 percent of the world’s reefs. The unprecedented three-year global bleaching, researchers believe, concluded this summer.

Even the fastest growing corals, like the spiny staghorn, need a decade to recover from a single bleaching. When corals survive an event, they’re left weakened and, in some instances, fail to spawn for the season. Two or more years of bleaching leaves little chance for survival. And events are predicted to grow more frequent. According to a 2016 study, the world’s reefs could face annual bleaching by the 2040s.

“It can’t be left up to scientists,” said Terry Hughes, director of the Australian Research Council Centre of Excellence for Coral Reef Studies. “The elephant in the room for coral reefs everywhere is global warming. Politicians get the message via the public who vote. We need better policies that focus on reducing carbon emissions and focus on renewable energy.”

Is that the only thing threatening the world’s reefs?

Reefs have a bully problem. Besides coping with higher ocean temperatures, they are susceptible to damage from storms. Earlier this year the southern portion of the Great Barrier Reef (which had been mostly spared by recent bleaching) was hit by a crushing cyclone. Pollution, such as fertilizer and other runoff from farms, can also impact reef health. In Australia, they are also dealing with the scourge of the crown of thorns starfish. Typically, the spiky starfish feed on faster growing coral and allow some slower-growing varieties to thrive. But crown of thorns populations can explode during periodic outbreaks, and the starfish will strip reefs bare.

How bad is the current situation?

The 2014-’17 global bleaching event is the “longest, most widespread and most damaging on record,” according to NOAA.

Two-thirds of the Great Barrier Reef have been affected, and scientists who study the system most closely are deeply concerned, using stronger and stronger language to describe the peril facing the natural wonder. Prior to these events, the barrier reef had already lost approximately half of its coral cover since 1985 due to the three plagues of bleaching, cyclones and crown of thorns.

While the Great Barrier Reef garners the most attention, other reefs, including those in U.S. waters, have suffered grave losses. In 2014-’15, Hawaii experienced its first bleaching events in consecutive years with 90 percent of the Aloha State’s reefs affected. Florida, boasting the only barrier reef in the country, was also hit by bleaching in 2014-’15. In 2016 researchers from the University of Miami found rising ocean acidity was degrading the state’s southeastern reef faster than expected.

“We don’t have as much time as we previously thought. The reefs are beginning to dissolve away,” University of Miami professor Chris Langdon, one of the study’s authors, told the Guardian in 2016.

How important are reefs to the wider ecosystem?

About as important as your lungs are to you staying alive. Reefs are vital to the balance and health of the ecosystem wherever they are found. They break waves, slow beach erosion and provide food and shelter for countless sea creatures. In many places, reefs are also essential elements of the local economy. Even though you’ll find coral reefs in just 1 percent of the Earth’s oceans, they support a quarter of all marine species in their vibrant, multihued nooks and crannies.

Currently, 22 coral species are listed as threatened and three as endangered. Sea creatures that depend on the reefs, such as parrot fish, spiny lobsters, whale sharks, hawksbill sea turtles and others could all be threatened with the continued loss of the world’s reefs.

The global economy would lose $1 trillion if all of the world’s reefs were lost, according to Australian non-profit the Climate Council,, based on figures showing 500 million people in 50 nations rely on the marine ecosystems, either indirectly or directly, for employment.

The largest coral reef system in the world, the Great Barrier Reef stretches 1,430 miles from its northern tip near New Guinea down to Australia’s Fraser Island in the south and is responsible for $7 billion in revenue annually, supporting 70,000 jobs. As news of the bleaching spreads, Australia has already seen the economic impacts. Visitor numbers are down 1 million annually, and 10,000 reef-related positions have been lost along with $1 billion in annual revenue.

A researchers conducts a survey of a stretch of reef impacted by bleaching in the Great Barrier Reef.

What’s Australia doing about it?

Depends on whom you ask. Australia actually argued against the UNESCO “in danger” status, with the country’s environment minister, Josh Frydenberg, calling the eventual decision a “big win” for the country.

“We are taking every action possible to ensure this great wonder of the world stays viable and healthy for future generations to come,” he went on to tell the Australian Broadcasting Corporation.

Australia is investing $200 million per year in a campaign to improve water quality, including measures to reduce agricultural runoff. Still, the government leaned on UNESCO a year ago to get the international organization to delete a section on the Great Barrier Reef from a report covering the potential effects of climate change. Additionally, the Australian government has approved the development of a new coal mine that would be the country’s largest and one of the biggest in the world.

In the June UNESCO report, the organization expressed “serious concern” over the 2016 and 2017 bleachings, and noted that Australia is not on target to meet its 2050 water quality goals. Calling progress “slow,” the report urged the government to accelerate its efforts.

What about the rest of the world?

One word: Crickets.

Many scientists thought 2016 would be the year that communities and governments took action. “There is hope among the scientific community that the events of the past year will be a call to action,” Mark Eakin, director of Coral Watch for NOAA, said in June 2016. “The hope is that people will finally listen and pay attention to climate change and the future of the reefs.”

There are some signs that tourist-dependent regions and governments are waking up to the risks. Mexico is trying out an innovative plan to protect its reefs off the coast of Cancún using an insurance system pioneered by Swiss Re and the Nature Conservancy. Hotels, resorts, guide companies and other businesses dependent on tourism will fund an insurance policy on a 40-mile stretch of reef. If storms or other events damage the reef, the payouts from the policy will then go to restoration efforts.

Yet, little has changed in a year. Few governments have implemented additional measures, and the United States recently declared it was abandoning the Paris climate agreement, which set some standards for reducing greenhouse gas emissions. Without a drastic reduction in greenhouse emissions, groups like the Climate Council say “extreme coral bleaching and the death of reefs will become the new normal.”

So, what’s next?

“It’s time to shift this conversation to what can be done to conserve these amazing organisms in the face of this unprecedented global bleaching event,” said Jennifer Koss, NOAA’s Coral Reef Conservation Program director. “We have boots on the ground and fins in the water to reduce local stressors. Local conservation buys us time, but it isn’t enough. Globally, we need to better understand what actions we all can take to combat the effects of climate change.”