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Rising Sea Levels Brought On By Climate Change Could Wipe Out The Great Barrier Reef 

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Climate change has drastically impacted our environment and its millions of inhabitants. In the 20th century, global sea levels specifically rose more rapidly than anytime within the past 3,000 years. By 2100, it’s projected to rise even further as climate change continues to escalate. 

The rapid melting of the Antarctic ice sheets is particularly becoming a problem, and reports show that sea levels can rise up to 5.2 feet from the melting. When sea levels rise, the multitude of ecosystems that exist throughout our oceans are negatively affected. 

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Scientists are looking at coral reefs in particular, as their ecosystems support the life of so many species. New research from Jody Webster, Juan Carlos Braga,  Marc Humblet, Stewart Fallon, and Yusuke Yokoyama, show that we can look at the history of coral reefs to better understand, and maybe even prevent, the future of Earth’s reefs. Their research was recently published in the publication Nature Communications. 

The team specifically looked at how the Great Barrier Reef in Australia reacted to a significant rise in sea levels around 13,000 to 10,000 years ago. Throughout history there has been a multitude of recorded “meltwater pulse events,” which refers to when ice sheets melt and dissipate in large quantities, causing global sea levels to rise. 

Sea levels rising can actually cause shallow-water reef systems to “drown,” due to the fact that corals and other organisms living in the reefs rely on the sun for photosynthesis. When the levels rise and the water becomes deeper, the organisms cannot properly perform photosynthesis to grow and thrive. 

An increased presence of sediment and rising temperatures brought on by climate change can also lead to drowning as it adds even more stress to the species within the reefs. 

The team said that by looking at cores from previously drowned fossil coral reefs can help give scientists an insight into what’s to come for the world’s reefs. Specifically fossil coral reefs that have been preserved on the continental shelf edge of the Great Barrier Reef. 

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These fossils reveal how past meltwater pulse events impacted reef growth, as well as how climate change specifically caused these melting events. 

“Although the Great Barrier Reef survived sea level rise roughly 11,000 years ago, the world was very different back then. Coral reefs faced less stress from human impacts. And ocean temperatures were rising more slowly,” the authors wrote for The Conversation. 

UNESCO’s World Heritage Committee has been reporting a high level of concern over the current state of the Great Barrier Reef and its future. Global warming, acidification of our Earth’s water, and pollution are also weakening our reefs. 

“Our findings suggest abrupt sea-level jumps of more than 11 meters are unlikely to occur without major instabilities in ice sheets. We’re in uncharted territory now, particularly with the Antarctic ice sheet displaying early signs of instability,” the authors wrote. 

“Our study also shows the Great Barrier Reef has been remarkably resilient, adapting to changing sea levels and continuing to grow even as the ocean rose rapidly. This resilience, however, had limits,” they wrote. 

The reef that they examined was found to have drowned about 10,000 years ago due to the multitude of stressors they cited throughout their observations. While there is hope from this evidence that shows reefs and their ecosystems can adapt to environmental changes, there will always be limits, especially as climate change intensifies. 

In order to protect our planet’s reefs, we need to use what the past has taught us. Reducing carbon emissions, protecting our oceans from pollution, and combatting environmental stressors brought on by humans is the key.

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How Coral Bleaching In The Great Barrier Reef Has Impacted Its Inhabitants

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Climate Change has caused countless environments throughout the world to be destroyed, ecosystems to change, and species to face endangerment/extinction. The Great Barrier Reef in Australia has faced some of the greatest challenges throughout the past decade, and now, its enduring its third mass bleaching event within five years.

The last time the reef endured a mass bleaching event as intense as this one is gearing up to be, a third of all corals were killed, and fish populations declined rapidly, which also caused the specific ecosystems/species within the reef to change for the worse as well. A recent study wanted to analyze what actual effects these bleaching events have on the fish species that live among the coral reefs, as that could help us better prevent these types of things from occurring in other reefs around the world.

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The scientists behind the international study used something called “gene expression” as a tool to understand how well fish are able to handle hotter temperatures, which is an effect of coral bleaching. According to the study, gene expression is “the process where a gene is read by cell machinery and creates a product such as a protein, resulting in a physical trait.” Using this process, scientists were able to predict which fish species would specifically be the most at risk/affected by repeated heat waves that lead to bleaching. 

The study initially began in 2015 when the researchers collected liver biopsies from several species of coral reef fish after global ocean temperatures increased by 1 degree Celsius that year, however, at the time the team of scientists had no idea how different everything would look in just 5 years; in terms of coral bleaching, ocean temperatures/acidification, and climate change in general. 

It wasn’t until one year later that things took a turn for the worse. In 2016, Jodie Remmer, a lead author on the study, along with one other researcher on the project went to the Great Barrier Reef to work on a completely different project when they realized that the ocean temperature around them read as 33°C. This was absolutely shocking in the worst way possible, as 33°C was the same temperature that Remmer claims to have been used in a climate change simulation where scientists predicted what the world would look like, environment wise, by the year 2100, meaning climate change has intensified to a much more urgent level than anyone expected by 2016.

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After one week, Remmer claimed they watched entire patches of coral reef turn bone-white, as fish populations abandoned their homes in search of new resources for food. During that time, scientists collected genetic samples from a multitude of fish and coral species. What they were looking for is how these species “switched their genes on and off” based on environmental conditions. Some genes should always be on, and others should be regulated and used as a response to things like temperature stress (like during a bleaching event). 

The ability to turn these genes on and off is what gives all species the ability to maintain proper metabolic, respiratory, and immune responses to environmental changes. When this gene expression is compromised, so is the ability to survive, hence the massive decline in coral reef ecosystems/fish populations. 

“Our findings not only have implications for specific fish species, but for the whole ecosystem. So policymakers and the fishing industry should screen more species to predict which will be sensitive and which will tolerate warming waters and heatwaves. This is not a ‘one size fits all’ situation. Fish have been on the planet for more than 400 million years. Over time, they may adapt to rising temperatures or migrate to cooler waters. But, the three recent mass bleaching events are unprecedented in human history, and fish won’t have time to adapt,” Remmer stated. 

Remmer went on to say that her and her team’s goal has always been to protect the ocean and all of its inhabitants as much as possible. This new information and data isn’t very encouraging, however, it does give scientists and the government the sense of urgency they often need in order to justify a global response.

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How Scientists are Using Sound Waves to Repopulate the Great Barrier Reef

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Climate change is transforming the Great Barrier Reef, turning a once lively and colorful underwater ecosystem into a massive coral graveyard. Already, about 89% of the reef is dead or dying, putting the future of countless species of underwater life in jeopardy. Once teeming with life, large sections of the reef are now eerily quiet, which scientists believe led fish to abandon this habitat. In an attempt to revitalize this dying ecosystem, scientists have installed loudspeakers in various areas of the reef to make them sound as though they are healthy. Scientists have observed that reefs that sound lively attract fish to return to these habitats, paving the way for a potential future project to restore, at least in part, the once-lively and diverse ecosystem of the Great Barrier Reef.

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Using a process they call “acoustic enrichment,” which they described in a report published by Nature, scientists played noises including “the crackle of snapping shrimp and the whoops and grunts of fish” via a network of underwater loudspeakers. The scientists observed that twice as many fish arrived, and stayed, in areas of the reef that sounded lively compared to equivalent areas where no sounds were played. As the presence of fish is necessary for sustaining the ecosystems of coral reefs, scientists hope that attracting fish back to the Great Barrier Reef will help to kickstart other life in the region, potentially undoing some of the disastrous effects of rising ocean temperature levels. In other words, scientists hope that making coral reefs seem to be teeming with life will attract fish, beginning a natural recovery process.

As the field experiment lasted only six weeks, scientists have not yet had the opportunity to determine to what extent the repopulation of coral reefs impacts the larger surrounding ecosystem. However, the success of the experiment thus far has provided hope that interventions using science and technology can mitigate the damage of ecological collapse caused by climate change and other effects of human activity. That being said, while acoustic enrichment has proven to be an effective strategy for attracting fish, a number of threats to the Great Barrier Reef as well as the larger underwater ecosystem remain and will have to be accounted for to ensure the ongoing health of the ocean. These threats include climate change, overfishing, and water pollution.

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The span of time during which scientists observed the reef was too short for the fish to start breeding, and as of yet it’s unclear whether the fish will stay in this habitat long enough to spawn multiple generations of animals and to revitalize the surrounding coral. Coral depends upon the natural byproducts created by fish in order to survive, as they work as vitamin filters that allow the reefs to absorb nutrients. And as up to 85% of the oxygen in the atmosphere comes from the ocean, the health of underwater reefs also directly impacts life above land.

While large swaths of the Great Barrier Reef are entirely dead, a small percentage of the reef remains alive, albeit less populated with life than they used to be. Other projects to revitalize sections of the reef have also been conducted, with varying degrees of success. For example, scientists working for the Mote Marine Laboratory grew small pieces of reef in the laboratory and implanted these pieces alongside compromised sections of reef, which helped to regrow coral in just a few years, as the implanted sections of reef reproduced naturally. Additionally, the University of Hawaii is undergoing a project to selectively breed species of coral that are resistant to bleaching by using specimens that have shown to be particularly resilient. There is a long, uphill battle ahead to preserve the Great Barrier Reef, but scientific interventions provide hope that such an enormous task is possible.

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Mother Nature Joins Effort To Save The Great Barrier Reef, But She Needs Our Help

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After a massive underwater volcano eruption in the Pacific ocean, a giant raft of pumice began floating en route to Australia’s Coast. Pumice is volcanic rock that is made up of dust or powder that is packed together and consists of a rough textured volcanic glass.

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There’s Hope For America’s Great Barrier Reef

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TAMPA, FLORIDA – The Florida Aquarium has made a groundbreaking discovery that could help regenerate what’s known as America’s Great Barrier Reef. The reef is found on the coast of the Florida Keys and is the planet’s third largest coral reef ecosystem. 

Since 2016, scientists and marine biologists alike have noticed a massive decrease in life within the reef. Climate change causes the waters that these reefs live in to heat up. Unnaturally warm waters cause underwater “heat waves” to occur. These waves last longer than normal heat waves on land do, due to the massive amounts of coral and other marine plant life that absorb the heat. 

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Withstanding high water temperatures for long periods of time can cause the coral to enter a “stressed” stage. When coral is “stressed” it expels itself of algae. The algae sits on the coral and is what gives it its vibrant colors, but more importantly feeds the coral. Without it, the coral starves and goes through a process called “bleaching”. It’s called this because without it’s colors and without the nutrients the algae gave it, the coral turns into a stark white skeleton of what it once was and dies, as seen in the image above.

This process is occurring all over the globe, including Australia’s Great Barrier Reef, which has gone through such severe bleaching, it’s only 50% the size of what it used to be three years ago.

However, there is a glimmer of hope. The staff at the Florida Aquarium have been working non stop on a project known as “Project Coral” to try to find a way to regenerate the rapidly decreasing coral populations. This past week, they reached a breakthrough.

With help from the experts at London’s Horniman Museum, scientists were able to successfully create coral egg deposits in a lab environment.

“It’s pure excitement to be the first to achieve a breakthrough in the world, our team of experts cracked the code…that gives hope to coral in the Florida Reef Tract and to coral in the Caribbean and Atlantic Oceans” says CEO of the Florida Aquarium Roger Germann in an interview with CNN.

The regeneration of coral spawn for coral that is native to the Atlantic ocean has never been done before and was previously deemed as “impossible” by scientists due to the higher temperature, density and salt levels in the Atlantic as compared to the Pacific. Well, it looks like the scientists at the Florida Aquarium we’re ready to prove everyone wrong.

The focus of Project Coral was specifically to help regenerate a type of coral known as pillar corals. These corals are what make up a majority of the Florida Reef, but also are known globally as the coral closest to extinction.

“With the success of this project, as a scientist, I now know that every year for the foreseeable future we can spawn Florida pillar corals in the laboratory and continue our work trying to rebuild the population.”

The Florida scientists have worked to try to recreate the natural environment of the coral when it reproduces. With the use of coral greenhouses (large fish tanks filled with coral and coral DNA), computer control systems, and LED technology, the scientists were not only able to build a perfect replica of the pillar corals natural environment in the Florida Keys Reef, but also the exact conditions the environment is in when the coral normally regenerates itself.

This monumental moment is an important first step in the global regeneration of all the coral that has been lost to climate change. This breakthrough is not only positive for the coral, but all the many ecosystems that are dependent on these reefs.

In addition to the environment regenerating, the economy will begin to as well, hence the importance of a project like this. The amount of money that comes into Florida (or any place around the globe that is home to a famous coral reef) from tourism is what keeps many businesses alive. With less coral alive, tourists are losing interest in these normally very popular vacation spots, and thus the economy is impacted.

However, with this new advancement the future for our planets entire ecosystem is just as bright and colorful as the coral reefs themselves.