"The Great Barrier Reef is in grave danger. The twin perils brought by climate change – an increase in the temperature of the ocean and in its acidity – threaten its very existence." - Sir David Attenborough

If those wise, powerful words from the voice of nature himself can't echo into the mindset of humanity quickly, then one of the world's most beautiful, natural ecosystems will vanish before our eyes.

Located off the coast of Far North Queensland, the Great Barrier Reef is both a UNESCO World Heritage Site and the world's largest coral reef system, with almost 3000 individual reefs and 900 islands. It has always been a beacon for divers and marine biology enthusiasts but in recent years it has started to deteriorate, to the shock and sadness of many. Through a combination of natural disasters, human intervention (over-tourism), and global warming, the once-thriving Reef is dissipating.

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10 Then: A flourishing ecosystem

The Great Barrier Reef has been known for decades as not only one of the world’s most diverse underwater ecosystems, but also as one of the premier diving spots in existence. For this reason, tourists and divers from all corners of the world move heaven and Earth for a chance to witness the incredible underwater world.

As told by WorldWildlife, Australia’s most iconic reef is host to “1,500 species of fish, 411 types of hard coral, one-third of the world's soft corals, 134 species of sharks and rays, six of the world's seven species of threatened marine turtles, and more than 30 species of marine mammals, including the vulnerable dugong.” It truly is a habitat like no other.

9 Now: Lifeless coral

Back in 2017, the Australian Government’s Great Barrier Reef Marine Park Authority released a damming graphic that showed the severity of coral loss across the four distinct areas: Far North, North, Central, and South. The percentages of dead coral across each region were stated as 26, 67, 6, and 1, respectively.

Since then, the numbers have only continued to get worse. Through a combination of coral bleaching, global warming, the aftermath of Cyclone Debbie, and tourists and swimmers unintentionally damaging the areas they swim in, the state of this incredible and iconic ecosystem continues to lose its color, beauty, and life.

8 Then: A colorful habitat for countless species

Prior to the tangible influence of global warming and the impact of the tourism industry in the area, the Great Barrier Reef was flourishing as a diverse habitat for all kinds of more underwater creatures to call home.

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What most people don't realize, however, is that the damage to the reef as a result of bleaching and tourism does not concern the entirety of the reef (thank God).

Marine biologist Rachael Jones stated, refreshingly, that in her region of study, they "haven't had any significant bleaching or coral disease because we're on the southern part of the Great Barrier Reef... I just keep seeing diversity of life here everyday because we're a green zone — you can't fish, you can't take anything, everything's protected by law."

7 Now: A mostly dull and bleak picture (but there's still hope)

It might be tough to see the stark contrast between a turtle swimming above a rainbow of flourishing coral and another turtle hovering above a sheet of the lifeless, bleached seabed. While it is a terrible reality, without a doubt, we can take solace in the fact that the damage is mostly situated in the northern part of the reef.

Even though it was severely impacted by the coral bleaching event as well as two cyclones in the space of five years, the media has portrayed it as if the entire ecosystem is under threat. Fortunately, there are still plenty of areas that are thriving which are out of reach for tourists.

6 Then: Before Cyclone Debbie rampaged

On March 28th, 2017, Cyclone Debbie turned toward the popular Queensland coastal town of Airlie Beach, tearing through houses and shelters and leaving the paradise looking more like something out of a post-apocalyptic film.

While not as obvious to the naked eye, the effects of Debbie stretched far beyond the mainland and well into the fragile structures of the Great Barrier Reef. Prior to her impact, the reef was a colorful artwork of underwater species that was already facing enough trouble, battling against climate change and over-tourism. The reef systems have a natural mechanism to revive after storms (old corals make way for new), but Debbie's impact was particularly strong and destructive.

5 Now: Coral bleaching taking its toll

Apart from the impact of tourism in the region and the devastating Cyclone Debbie which ripped apart the tourist town of Airlie Beach and plenty of the underwater systems, the main reason for parts of our beloved Great Barrier Reef deteriorating is coral bleaching. We've thrown that concept around a few times already, but what exactly is it?

Essentially, coral bleaching is the ecosystem raising the white flag in the battle against global warming. It's a visual, tangible change that forces humanity to realize the impact that our actions are having.

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The worst bleaching event by far occurred in 2016 and was triggered by record-breaking temperatures on the ocean's surface.

4 Then: Thriving Orpheus Island

This image was taken back in 1996, displaying a thriving shoreline ecosystem on the northeast of  Orpheus Island, dubbed by Australia.com as "a secluded Great Barrier Reef Island that offers immaculate coastlines and a truly memorable tropical escape."

Unfortunately, like many other islands in the popular regions of the reef, Orpheus Island has suffered from the effects of global warming, natural disasters, and tourism. Its position on the shoreline makes it more susceptible to damage from powerful winds, rising shorelines, and strong waves.

3 Now: Not-so-thriving Orpheus Island

This comparative photo was taken back in 2016, highlighting a clear juxtaposition between a thriving ecosystem and an eroded, damaged shoreline.

Over the years, Orpheus Island has become a popular base for travelers and marine enthusiasts wanting to explore the vibrant ecosystems around the Palm Island Group. It attracts a handful of extra tourists during the months of July and August, when there's a good chance of spotting a few Humpback Whales en route to the Yanks Jetty. Unfortunately, this spike in tourism is part of the reason for its downfall.

2 Then: Tourists didn't realize their impact

Tourists used to (and continue to this day) flock from all corners of the world to dive, snorkel, and swim in the vibrant and picturesque waters of the world-renowned Great Barrier Reef.

Unfortunately, this popularity has had a direct correlation with the deterioration of trafficked regions of the reef. Divers unintentionally brush against coral or take a little piece home for themselves. The boats which transport tourists to and from the dive zones can rip apart shallow groups of coral if they take a wrong turn too.

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Tourists are finally starting to recognize the impact they're having, and - better late than never - doing something about it. Marine biologist Rachael Jones says "tourists are more worried about the reef than previously because of the way it is portrayed in the media."

1 Now: Temperatures continue to rise

Over the last 110 years, Australia's oceans have increased in temperate by one degree. That might seem like nothing, but for such a small number, it's incredibly dangerous. The increase has caused sea levels to rise, and acidity in the oceans to increase, and they're predicted to continue in this direction as well.

Senior Australian Scientist, Dr. Helen Cleugh, says (as told by the Great Barrier Reef Foundation) that "Australian temperatures will almost certainly continue to increase over the coming decades, with the pattern of more extremely hot days and fewer extremely cool days affecting both land and sea."

If we don't do something soon, we're in trouble.

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