A new sobering report from the US National Oceanic and Atmospheric Administration (NOAA) has revealed that coral reefs are experiencing “bleaching” which has the potential to slowly poison and destroy 38% of the world’s coral reefs. This comes as little surprise to climate scientists, as coral bleaching is one of the results that comes from the ocean absorbing over 90% of global warming.
What is coral bleaching?
Coral bleaching is when a coral reef experiences a sudden and abrupt change in conditions such as exposure to light, temperature, and nutrients. Feeling this stress causes the coral to expel the symbiotic algae living alongside it, and to turn completely white. Stephanie Wear of The Nature Conservancy explains in depth:
The first thing to understand is that corals get their brilliant colors from tiny algae that live in their tissues. These tiny organisms live in harmony with coral animals, and they basically share resources,” Wear explains. “For example, the most important thing that the algae do is provide food to the corals through carbohydrates they produce during photosynthesis.”
The next thing to understand is that corals have a limited temperature range within which they can live,” When it gets too hot, they get stressed out—and this relationship with the algae goes sour. The tiny algae are ejected from the corals, turning them white, thus the term ‘bleached.’If these algae aren’t reabsorbed in the near term, the coral will die, they just can’t survive long-term without them.”
Has coral bleaching occurred before?
This is the third major warming event in recorded history, with the previous two being in 1998 and 2010. In those two cases coral bleaching occurred in all major oceans and in 1998 16% of corals affected by bleaching died off completely. Dr. Mark Eakin, the coordinator of the US National Oceanic and Atmospheric Administration Coral Reef Watch programme, believes that this will be the cataclysm that he has feared since 1998:
The fact that 2016’s bleaching will be added on top of the bleaching that has occurred since June 2014 makes me really worried about what the cumulative impact may be. It very well may be the worst period of coral bleaching we’ve seen
Many scientists now believe that this will be the worst of all coral bleaching catastrophes, and are predicting that every year could very well be a bleaching year by 2030.
Science saw this coming
The current bleaching takes its beginning from the El Nino event in 2009, which scientists realized closely resembled the 1998-99 El Nino and began to fear that a significant bleaching event was coming. Moreover, in 2014 when Hawaii began to experience significant bleaching scientists began to see an additional “giant red blob” of warming in the Pacific Ocean that was not part of the El Nino event which could prove to be devastating to marine life in Hawaii, Guam, and California.
The “blob” as named by University of Washington meteorologist Nicholas Bond who first observed it in 2013, spans 500 miles, has no known explanation to this point, and is the longest running temperature anomaly in current historical record. Scientists are struggling to explain the event, but believe it to be responsible for starving sea lion pups in California as well as other environmental issues on the west coast of the United States.
If this blob, or the El Nino get worse and begin to head towards Australia in the South Pacific then a true disaster could occur as Australia’s Great Barrier Reef comes under attack. The Great Barrier Reef is the largest coral reef in the world, and losing even a part of it to bleaching would constitute a tragedy against earth’s biodiversity
Scope of the damage
Coral reefs are a relatively small part of the ocean with just 0,1% of earth’s ecosystems, but much like the rain forest they house much of the ocean’s biodiversity. Currently, coral reefs are home to 25% of marine species, serve as buffers for shorelines, support fishing industries, and are tourist attractions.
If coral bleaching continues then the NOAA predicts that 500 million people could see their livelihoods impacted as well as up to 30 billion dollars lost each year. Global demand for seafood is now at an all time high according to the World Bank and if coral reefs experience major bleaching and fish suffer habitat loss then meeting high demand for seafood will become even more difficult.
Can we stop coral bleaching?
While some coral reefs do recover from bleaching, according to Prof Rupert Ormond, Secretary of the International Society for Reef Studies there is a finite window for recovery:
Although corals may live for several days after they bleach, they then usually die. They may recover – but only if the sea temperature drops within a week or so. Mostly it takes much longer, so the reef ends up covered with dead corals, especially on its upper parts.The reefs may slowly recover if new coral colonies come in from outside, but this may take years or decades. I know coral reefs in Kenya that lost most of their corals in 1998 and they still only have a few percent of the corals once there.”
So while recovery is possible, it is unlikely to happen. However, some hope may exist for saving the coral reefs using some of the same techniques that we use in our gardens.
Scientists are now breeding corals in special facilities and exposing them to different temperatures in hopes of find a breed of algae that is more hardy and capable of withstanding higher temperatures and rates of ultraviolet light.
To replant the coral a 12 foot cage with a low level electrical current can be sunk down into the water and planted with coral. The electrical current creates a chemical reaction that draws in calcium carbonate and creates a rich environment for which coral can grow. Coral growth on this “Lotus” structure is 5 times faster than normal coral growth, and the growth is so strong that the original steel cage is barely noticeable now. The designer of the Lotus, Wolf Hilbertz, died in 2007, and while he believed his invention could be used to save the world’s coral reefs the reality is that it is too expensive to be implemented on a global scale.
Only one true solution
Coral reefs are reacting to warmer waters, but the cause of this is increased carbon emissions. A 2014 study found that carbon emissions were increasing at the fastest rate in 30 years, and show no sign of slowing down. Without a significant reduction in C02 emissions then the coral reefs which we enjoy today will become a shell of themselves, according to Peter Sale this day is rapidly approaching:
“By 2050, we may still have corals, and things we’ll call ‘reefs’, but they will be massive limestone structures that were built in the past, with tiny patches of living coral struggling to survive on them,”
Soon the time to find a solution for global warming will be too late, and if a solution is not found, then one of our planets’ greatest sources for bio-diversity will be lost forever.