Australia is blessed with having one of the seven natural wonders in the world within its waters, The Great Barrier Reef. It is the world’s largest coral reef, is rich in marine life and consists of at least 3000 separate reef systems. The great barrier reef has grown to become one of the most desired tourist attractions (greatbarrierreeforg, n.d). But recent studies prove that with heat waves, the coral is dying off (ARC, 2018).
The lands and oceans are warmer than ever, and still rising in temperature. Records kept since 1880 show the globe is heating up, this rise in temperature is called global warming (Pappas, 2017). The combustion of fossil fuels is the current cause of global warming. The hydrogen and carbon are heating up our globe through the Greenhouse effect, an effect caused via interaction of the atmosphere and radiation entering from the sun (Pappas, 2017). The difference in average surface temperature between 1880 and 2016 is almost +1 degrees Celsius, and the speed of this change is rising 0.07 degrees each decade, with the land warming even faster than the ocean (Pappas, 2017). Global warming occurs faster in certain parts of the world (Ward, 2001). (Please see appendix two for interview with WWF)
This report will discuss the impact that global warming is having on the flora and fauna of Australia’s Great Barrier Reef.
When the oceans water gets too warm, the corals will remove the algae (zooxanthellae) that lives in their tissues, turning the coral completely white (National Ocean Service, 2018). Once the coral has been bleached, it is not dead, but is under more stress. The coral can survive the bleaching but are vulnerable to mortality (National Ocean Service, 2018).
If coral is affected by a heatwave, its colour will fade and it’s left with two outcomes, it will either survive and slowly regain its colour as the temperature drops, or it dies. In just nine months of 2016, 30% of coral died from the Great Barrier Reef from heat (Hughes, 2018). The northern third of the reef was found to be the most extremely affected (shown in figure 1 on page one of appendix) after scientists graphed the geographical pattern of heat exposure (Hughes, 2018). “We’re now at a point where we’ve lost close to half of the corals in shallow-water habitats across the northern two-thirds of the Great Barrier Reef due to back-to-back bleaching over two consecutive years.” stated Professor Sean Connolly of Coral CoE at James Cook University (N.D). See appendix page one for a diagram of the Great Barrier Reef and the different affected areas, northern, central and southern. It has colours representing how badly that area is affected.
Figure two (please see appendix page one) indicates just how much the climate has changed since 1900 up until 2016. The graph shows the surface temperature of the reef. And in a century, the average temperature in March has shifted from a low of -1.7 degrees Celsius to almost +2.0 degrees Celsius. It also indicates that the temperature is still increasing dramatically.
Bleached coral in the Great Barrier Reef
Pre and post coral loss from 1960 – 2017
The Great Barrier Reef Marine Authority estimates that there are the following numbers of species that depend on the Great Barrier Reef ecosystem: (Please see appendix page two for food web)
• 1625 species of fish,
• 215 species of birds
• 6 of the 7 marine turtles are found here
• 133 species of sharks and rays
• 30 species of whales and dolphins (N.D)
The reason there is so much marine life in this area is because it provides them with habitats and shelter and provides nitrogen and other essential nutrients for marine food chains (Queensland museum, n.d). But, animals such as the Green Turtle and the Hawksbill Turtle are being impacted by this major issue of coral bleaching as both species, along with many more rely on living, feeding and nesting on the reef (WWF, 2018). Plankton is a species which forms the base of the marine food chain for coral, but is affected by global warming (WWF, 2017). The Intergovernmental Panel on Climate Change believe that by the end of the century, there will be a further rise of between 1.4 degrees Celsius and 5.8 degrees Celsius (WWF, 2017). This could absolutely be the finishing blow for the species that are already under stress from things such as habitat loss.
The great barrier reef generates over 1.5 billion dollars every year for the Australian economy (Queensland Museum, n.d). If it is destroyed, Australia will lose one of its greatest natural phenomena (WWF, 2018). But there will also be a huge economic impact particularly in areas dependent on tourism.
The Great Barrier Reef has a massive total economic, social and icon credit value of $56 billion and supports Australia with 64,000 jobs (Great Barrier Reef Foundation, 2018). So, if the great barrier reef is destroyed then there will be a massive decrease in tourist visiting which is the biggest contribution to these huge numbers.
What’s being done?
The government have a 2050 sustainability plan for the reef, “To ensure the Great Barrier Reef continues to improve on its Outstanding Universal Value every decade between now and 2050 to be a natural wonder for each successive generation to come.” (Department of the environment and energy).