How is Global Climate change affecting coral reefs ? A.N.Other

What are coral reefs? Coral reefs are underwater structures made from calcium carbonate secreted by corals. Corals are colonies of tiny living animals found in marine waters containing few nutrients. Most coral reefs are built from stony corals, and are formed by polyps that live together in groups. The polyps secrete a hard carbonate exoskeleton which provides support and protection for the body of each polyp. Reefs grow best in warm, shallow, clear and sunny waters. Often called “rainforests of the sea”, coral reefs (below) form some of the most diverse ecosystems on earth. They occupy less than 1% of the world ocean surface, about half the area of France, and they provide a home for 25% of all marine species, including fishes, molluscs, echinoderms and sponges.

Where the coral reefs can be found They are mostly in the North Pacific ocean. Some of them are in the Indian ocean and South Pacific. On these maps the coral reefs are shown by the pink and red blobs. Most of the coral reefs are near the Equator, between the tropics. The most famous coral reef is the Great Barrier reef which is in Australia. Half of the worlds coral reefs are endangered. In most coral reefs there are less corals and fishes than there were only a few decades ago.

What is global climate change ? Global Climate Change (or more commonly known as global warming) is getting worse every year. Global warming is when the temperatures get abnormally higher and higher. The IPCC (Intergovernmental Panel on Climate Change) conclude that most of the temperature increases since the 20th century was probably caused by the increases of greenhouse gases from things such as fossil fuel burning and deforestation. These graphs show the change of temperatures over the years global warming isn’t just recently. But what we’re doing now is more destructive than then.

Global warming's affect on Coral reefs Global climate change affects coral reefs by: Acidification The third and in many respects the greatest concern in the longer term, is that global change is causing the world’s oceans to become more acidic. Coral loss There are many causes of local and global coral loss but human-induced climate change is one of the main and undeniable threats. Climate change is having negative effects on coral populations via at least three mechanisms. Coral disease Ocean warming can also indirectly kill corals by magnifying the effects of infectious diseases, which are one of the primary causes of coral loss, particularly in the Caribbean Coral bleaching First, ocean warming is directly reducing coral cover through coral bleaching. Reef-building corals contain plant-like organisms called zooxanthellae that live symbiotically within their tissue. Coral bleaching is caused by elevated sea surface temperatures due to global climate change which the animals cannot cope with..

How is Global Warming Affecting the Ocean? Carbon dioxide, methane, and other greenhouse gases trap heat, leading to global warming. The increase in ocean temperature is 1° C over the last several ten years. But even such changes have caused mass-coral mortality events around the world. During some of the especially warm summers, over the last ten years. In the Pacific and Indian Oceans, coral bleaching is widespread. Causing mass coral mortality in many countries. For example, in Palau, more than 90% of the corals reefs are bleached and at least 50% perished. Even some isolated reefs were impacted. In the Maldives, in the east Indian Ocean, bleaching caused coral cover to plummet to only about 5%. Predicted increases in CO 2 under different IPCC scenarios. (Source: IPCC 2001)

Coral Diseases Over the last 30 years scientists have found about 30 coral diseases. The causes and effects of coral disease are not properly understood. Coral diseases can be caused by bacteria, fungi, algae and worms. Coral disease have a major impact on Caribbean reefs, where 80% of coral has been lost to disease in the last 20 years. About seven diseases have been recorded from coral in the Great Barrier Reef and they are not thought to be a major threat to the Reef.

Steve Irwin and David Attenborough People are interested in the preservation of coral reefs such as Steve Urwin and David Attenborough. David Attenborough joined scientists July 2009 on the 7 th to warn that carbon dioxide in the atmosphere is already above the level which could cause coral reefs to become extinct in the future, with horrible effects for the oceans and the people who depend upon them. Steve Irwin, known everywhere as the “Crocodile Hunter,” died on September , after being pierced in the chest by a stingray barb while filming an “Ocean’s Deadliest” in Australia's Great Barrier Reef.

Conclusion and Future I conclude that global climate change affects coral reefs by bleaching, coral loss and ocean acidification. This is due to the gasses that trap heat being in the ocean and bleaching the coral. In % of all coral reefs were facing extinction due to this problem could be the turning point to all this. If we act now we could change this and pursue the problem and sort it out. Hopefully in years to come the coral reefs will still be around and evolving as they should. Evaluation I mainly used Wikipedia and education sites such as enchanted learning. Education sites were very useful because they have lots of information on coral reefs. 5

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