Over the last 40 years, ocean temperatures and sea levels have been rapidly rising, but we are only starting to realise the devastating effect this can cause to life underwater and us.
We have seen beautiful flourishing ecosystems built over centuries destroyed by climate change in just a matter of a few years. Not only does this affect life underwater and the environment around the area, but it is also affecting us, humans. There are many examples of ocean life being severely damaged by climate change. In recent years, people have started to realise that the coast of California had been heavily damaged by the effects of climate change. But without a doubt, the most heavily affected areas would be the Great Barrier Reef (GBR), located off the coast in Queensland Australia.
Professional underwater photographer Al Hornsby shared with us a first-hand experience of how life underwater had been impacted by climate change. Al was talking about how he went to the GBR for the first time, expecting to see vibrant colours of corals on the bed of the reef, only to see white corals everywhere. The white corals turned out to be corals that have been through a process called bleaching, a result of an impact from climate change. He said that though the white corals were still an amazing and mystical sight, it was still upsetting to see that these corals had to face the consequences of global warming. Coral bleaching not just affects how the corals look but also signifies how healthy the corals are. With this much coral bleaching happening in one area, this can have a knock-on effect on the surrounding corals and animals who rely and depend on corals for survival.
A photo of the Great Barrier Reef with a large area of bleached coral (Source Carbon Brief)
What do coral reefs do?
According to the WWF, “Coral reefs provide shelter, spawning grounds, and protection from predators.” Furthermore, coral reefs also support animals at the base of the food chain. Animals such as turtles, fish and jellyfish heavily depend on coral reefs for survival. Fish use corals as a shelter during the day and will rely on them to hunt for food at night. Similarly, turtles also use corals as shelter. Without the support of coral reefs, many animals which already face the risk of extinction could go extinct if the current situation continues.
What is causing the coral bleaching?
The bleaching of coral reefs is a direct effect of climate change. Climate change refers to the general effect of change in climate patterns, often meaning irregular climate patterns including the rise in sea temperature at the GBR. According to the National Climate Change Adaptation Research Facility, the sea surface temperature at the GBR has increased by about 0.6 degrees Celsius since the 1950s. This may not seem like a huge change in temperature, but for animals and organisms that are sensitive to temperature, such as corals, this is a massive change in temperature. In addition to this information, The Intergovernmental Panel on Climate Change predicts that “by 2035 the average sea surface temperature will be warmer than any previously recorded” further showing the effects of climate change.
Change in temperature is one of the biggest causes of coral bleaching. Though there are complex processes that go behind how coral bleaching works, I will put it in simpler terms. Because corals are sensitive to change in temperature, when the temperature of the water around the coral changes, this forces the algae responsible for the colours of the coral to leave the tissues of the coral. This causes the corals to lose colour. When this continues over a long period, this can eventually lead to coral bleaching, turning the corals completely white. When corals are bleached for a long period this causes them to die.
Photos comparing before and after coral bleaching (Sources Eco-Business, Wikipedia)
What are the impacts of coral bleaching?
When coral reefs die, whole ecosystems are affected. Many organisms such as fish and turtles lose their habitat. This will destroy entire ecosystems. Without the protection of corals, the fish will be a lot more vulnerable to their predators, leading to fewer numbers of fish. This will create an unstable ecosystem, even affecting us. With the ever-growing number of humans, people will need to gather more resources to feed the increasing population. With the number of fish getting fewer and the population of humans increasing, there is a higher possibility of more species of life underwater getting in danger of becoming extinct.
Coral reefs also have a direct impact on human life. Many people rely on coral reefs for a source of income. Local businesses such as diving tours and restaurants will be majorly affected by the loss of coral reefs. According to the Great Barrier Reef Foundation, coral reefs have a total economic value of 56 Billion dollars and annually contribute 6.4 Billion dollars to the economy. The loss of coral reefs not only affects the economy but will also affect lives living near the coral reefs. According to the National Ocean Service, “The coral reef structure buffers shorelines against waves, storms, and floods, helping to prevent loss of life, property damage, and erosion” further showing the importance of coral reefs and the positive impact coral reefs have on us.
Connection to the SDGs
The issue of coral bleaching in the GBR also directly connects to the SDGs number 13, Climate Action and number 14, Life Below Water. Climate action is a big contributor to this issue. If we can resolve the goal of Climate Action, the issue of coral bleaching in the GBR can come closer to being solved. With number 14, Life Below Water, the most affected and directly impacted are life below water. Recognising that issues like these are connected to the SDGs is an important thing to remember. Especially at UWC where we are focused on contributing to resolving the SDGs, it is important to be aware of these connections.
SDGs number 13 and 14 (Sources Sustainable Development Goals Knowledge Platform)
Course of action
As individuals, the most important first step for us to take is to understand the issue and think about why it may be important for us to acknowledge the issue and make personal goals to contribute to the solution of the problem. Another simple step we can all take is to raise awareness of the issue. When larger numbers of people understand the issue, more people are likely to act on it, helping people gain an understanding of the issue better. Other steps that can be more hands-on can be to change personal habits that could be contributing to climate change. Though many factors contribute to climate change, what is most important is to take the first small step. Some examples can be trying to use methods of transportation that will have a lower carbon footprint. Another example would be to cut down on meat for one day of the week. According to the organisation Meatless Monday, eliminating meat for one day of the week “could reduce emissions by an estimated 1.0 Gigaton (Gt)ii to 1.3 Gt iii,iv per year” Though this can be seen as a small change in our habits, this can have a huge overall impact on the environment.
I think that contributing to the solution of climate change is something that everyone can work towards and something that we should be doing. Many people tend to not act on trying to find a solution for climate change as they think that it won’t affect them or have a significant impact anyways. Climate change is something that affects everyone on a global level and has long-lasting effects if we do not act towards solving this issue. With the GBR, if we do not change our actions, corals will continue to get damaged and many more animals will lose their habitats or become extinct if we do not act towards the problems that we currently face. Climate change is something that we have all collectively caused. If we can put the world in such a horrible state, shouldn’t we have the ability to put the world back to when it was less damaged?
Daisy Dunne, Great Barrier Reef at ‘unprecedented’ risk of collapse after major bleaching event, Carbon Brief, 18 April 2018
Great Barrier Reef Foundation, CLIMATE CHANGE, Great Barrier Reef Foundation
Great Barrier Reef Foundation, THE VALUE, Great Barrier Reef Foundation
Great Barrier Reef Marine Park Authority, Sea temperature, Great Barrier Reef Marine Park Authority
International Union for Conservation of Nature, Coral reefs and climate change, International Union for Conservation of Nature
Lorin Hancock, Everything You Need to Know about Coral Bleaching—And How We Can Stop It, WWF
Meatless Monday Global, The Meatless Monday Global Tool Kit, Meatless Monday Global, September 2016
Mongabay.com, Australia to invest $379 million to preserve the Great Barrier Reef, Eco-Business, 4 May 2018
National Oceanic and Atmospheric Administration, How do coral reefs protect lives and property?, National Oceanic and Atmospheric Administration, 15 November 2019
NCCARF, Climate change and the Great Barrier Reef, NCCARF
United Nations, Helping governments and stakeholders make the SDGs a reality, Sustainable, Development Goals Knowledge Platform,
Vardhan Patankar, File:Bleached coral, Acoropora sp.jpg, Wikipedia, 12 May 2016