It is with great sadness that we announce the passing of the Great Barrier Reef, the world’s largest living ecosystem and a Unesco World Heritage site. A 622-mile-long sector of the reef has succumbed to bleaching due to warming seas.
The passing of the reef is a tragedy for everyone but this is particularly true for the diverse array of species that have been rendered homeless. This includes 15,000 different types of fish, as well as whales and dolphins. While this obituary is for Australia’s iconic aquatic landmark, thousands of other lesser-known coral reefs have also been bleached by a warming ocean. Other reefs that are being destroyed by bleaching include those off the coast of the Philippines, the Caribbean, Florida Keys, and Fiji’s nearshore waters.
The relationship between coral bleaching and climate change is clear, as Australian scientist Justin Marshall of the University of Queensland explained: “What we’re seeing now is unequivocally to do with climate change.” Coral bleaching is directly related to warm ocean temperatures which cause corals to expel the symbiotic algae that live in their tissues. In the absence of algae, corals are deprived of a significant source of food and they are commonly killed by disease. Climate change, specifically warming ocean temperatures, is the primary cause of coral bleaching.
This is the third major coral bleaching event and the worst ever recorded (the first happened in 1998 and the second in 2010). This most recent event is the longest. It started in 2014 and it is expected to extend well into 2017 causing what is expected to be the biggest coral bleaching event in history. The longer the event the more likely that these corals will starve to death. The increasingly frequent and longer-lasting bleaching events that are killing corals are outpacing their ability to recover.
More than ten percent of the world’s coral reefs have been completely destroyed, almost a third are considered seriously damaged and more than half (60 percent) of the remaining coral reefs may die within the next 20 years. We can see what this looks like in places like the Philippines where 70 percent of coral reefs have already been killed. Corals all around the world are teetering on the brink of a similar fate.
As the most diverse marine ecosystem on earth, the death of coral reefs amounts to a form of aquatic genocide. While many do not realize it, our destruction of the oceans and corals in particular directly imperil human life as oceans are a crucial source of food and they support the livelihood of 500 million people around the world. This is an economic disaster that translates to widespread food insecurity. Coral reefs protect shorelines against the ravages of extreme weather which are also exacerbated by climate change. The loss of the biodiversity of coral reefs also deprives us of an important as yet untapped source of medicines.
According to a 2006 UNEP report, coral reefs are one of the world’s most valuable ecosystem services. They comprise an area of almost 300 000 km² and have an economic value of US$100 000-600 000 per km². Human activity is to blame for the decimation of corals around the world. The primary cause is anthropogenic climate change, specifically warming oceans. Humans are also killing coral reefs in five other ways:
3. Nutrients that lead to algal growth that smothers the coral
4. Over-fishing has led to increases in predator populations that eat corals
At the end of March, an aerial survey showed that Australia’s Great Barrier Reef is 95 percent bleached, and half of it is either dead or dying. The survey looked at the 1,400-mile-long Great Barrier Reef and found that out of 520 reefs surveyed, 95 percent were experiencing “severe” bleaching.
A February press statement from the American Geophysical Union and scientists from the National Oceanic and Atmospheric Administration sounded the alarm. They report that rising ocean temperatures from global warming and the strong El Niño are expected to extend the ongoing coral bleaching event. As reported by the Guardian, by the end of this year 38 percent of the world’s remaining coral reefs are affected and 5 percent of these coral reefs will not recover.
Professor Ove Hoegh-Guldberg, director of the Global Change Institute at the University of Queensland, Australia, said the ocean was now primed for “the worst coral bleaching event in history”. Hoegh-Guldberg has predicted that global temperature rise will lead to the complete loss of coral reefs by the middle of this century.
One of the ways that we can help coral reefs to recover is by making them into protected areas. As reported by Grist, President Obama has established new national marine monuments and Palau turned most of its territorial waters into a marine reserve. However, the best way to help coral reefs is to radically reduce global warming causing emissions.
Warming oceans are killing the coral and this is primarily caused by the burning of fossil fuels. As reviewed in another Guardian article, the “Link between fossil fuels and Great Barrier Reef bleaching clear and incontrovertible.” The bleaching is due to record ocean temperatures, which are caused by atmospheric warming attributable to fossil fuels.
The coal industry in Australia is an especially virulent climate offender. As the industry fights for its survival it has tried to cast aspersions on the well-documented body of evidence showing how fossil fuels are driving global warming. What makes this situation even more deplorable is the fact that in an attempt to justify the growth of coal exports, the Australian government is complicit in the subterfuge. Australian ministers have traveled the world trying to convince people that the reef is not in danger. While some would like to blame El Niño for the bleaching this is simply not true. El Niño has been around for centuries and has not caused anywhere near this level of bleaching.
Despite the dying coral reefs, the Queensland Government has approved mining leases for the $21.7 billion Carmichael coal mine and rail project in the Galilee Basin. Greenpeace Australia Pacific spokeswoman Shani Tager issued a statement that called the State Government’s decision “appalling”, and she decried the fact that it came as the Great Barrier Reef suffered severe coral bleaching. “Coral scientists, the Great Barrier Reef Marine Park Authority and even the Queensland Government have acknowledged the severity of this latest bleaching,” she said.
“The federal and Queensland environment ministers are wringing their hands, despairing over the state of the Great Barrier Reef, yet at the same time, they are paving the way for the nation’s biggest coal mine – a development that can only harm the reef. Protecting the reef and approving the Carmichael mining lease are diametrically opposed – you.” Tager said.
Coral reefs have been in our oceans for hundreds of millions of years, yet humans have managed to destroy them in a few hundred years. We have good reason to be alarmed as corals are like the canary in the coal mine. The fate of life on Earth, including human life, is tied to the health and well-being of our oceans and our coral reefs.