Sunday, February 22, 2015

Climate Change Effects on Coral Reefs

Photo from
Healthy coral vs dead/dying coral due to effects of climate change

One of the most threatening factors to coral reefs around the world is climate change. Climate change affects the atmosphere, increasing the levels of carbon dioxide in the air. With this increase in carbon dioxide, the Earth as a whole gets warmer. When the Earth gets warmer, the temperature of the oceans increase as well. These increases in temperature are extremely harmful to the coral reefs of the world; they cause the corals to become bleached and die off. 

Steve Palumbi, a professor of marine science at Stanford University, explained what coral bleaching was in an interview with Steve Curwood for Living On Earth’s magazine. Palumbi says, “Coral bleaching is an event that happens when the water temperature gets a little too high for the coral. … And when that water temperature heats up, that algal interaction with coral breaks down and the coral splits the alga out. … It is called bleaching because they turn white before they die.” (Curwood) Some scientists believe that the rise in water temperature only weakens the coral, making them have a higher probability of getting sick and be resilient toward rising temperatures in the future. (The New York Times) This is such a predicament because coral rely heavily on the algae in the water for their survival. If the temperatures continue to rise, more algae is expelled out from the corals making more and more coral die year by year.

Photo from Tropical Marine Biodiversity
Number of species of coral around the world

In a news article from The Guardian, it says that researchers believe that most of the world’s corals could be gone by the year 2100. The article states that researchers have found that the rate at which corals are dying are far greater than the rate at which they are staying healthy and living. Currently, the amount of carbon dioxide in the air is around 388ppm, and it is expected to be at 560ppm by the end of the century. (The Guardian) If the atmosphere reaches this level, it is a concern that around 9,000 corals will be no more. What’s even more upsetting is that almost half of the corals in the world have already been destroyed over the last 30 years due to climate change. (The Independent) If climate change continues to change atmospheric and water temperatures, it is without a doubt that most of the world’s coral will be dead soon.

There have been countless efforts in attempting to stop or at least slow down the process of coral bleaching in the world. Australia is looking to invest about 8 million dollars over the course of five years to protect the Great Barrier Reef from the pollution and threats (like climate change) that the coral have been facing. (BBC Australia) This will be beneficial to those coral reefs because they've already been weakened by things like pollution that continued climate change effects make them more susceptible to larger damage. Their government also has a plan to further protect the Great Barrier Reef with the “Reef 2050 Long-Term Sustainability Plan”. Palumbi’s research could help aid in this plan to protect the corals; his team happened to find a group of corals in the back reef lagoons of the American Samoa that were thriving off of the heat; they are using this area/information as insight to find out how this is happening, and why the corals are surviving so well. If they are able to find answers to this, it may help us find ways to save the corals around the world suffering from the high temperatures of the oceans. (Curwood)

Overall, it is extremely evident that climate change is, indeed, happening, based on the fact that there is evidence of destroying corals all over the world. If these corals die off and become non-existent, the whole marine ecosystem will be in danger. Coral reefs are also very crucial to the marine ecosystem; when the coral is healthy, they provide food, shelter, and nursery grounds to the marine life around them, as well as serve like a storm buffer to land around the area. To quote Mitchell Ramsey on the seriousness of the effects on the marine ecosystem, he says, "The oceans is the home to over one million species, and the ocean is so large that there may be another million species out there to be discovered." Rehabilitation efforts, whether it be governmental support or help from organizations, need to be continued and taken seriously. It would also help if there were more education to the communities on the subject so people can be more aware of the seriousness of the topic. With these

Bawden, Tom. "Race to save Coral Reefs from Destruction 'could Be Lost within 10 Years'; UN Warns 50 per Cent of 'rainforests of the Sea' Destroyed by Climate Change in 30 Years." The Independent [London] 24 Sept. 2013.

Curwood, Steve. "Living on Earth: A Bright Spot for Coral Reefs." Living on Earth. Living on Earth, 11 Jan. 2013. Web. 03 Feb. 2015.

"Protecting Great Barrier Reef 'needs A$785m' Fund." BBC Australia. BBC Australia, 19 Jan. 2015. Web.

Ramsey, Mitchell. "A Changing World with the Changing Climate, Part III: The Oceans." Web log post. Blogger, 1 May 2014. Web. 22 Feb. 2015.

Sample, Ian. "World's Coral Reefs Could Disintegrate by 2100." The Guardian. The Guardian, 23 Feb. 2010. Web.

The Associated Press. "Most of Hawaii's Coral Recover From Mass Bleaching." The New York Times. The New York Times, 28 Jan. 2015. Web. 03 Feb. 2015.


  1. Here is a cool (!) report about how mangrove forests can serve as refuges for coral populations otherwise being damaged by warming and bleaching (plus some attractive photos):

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