Why is the Great Barrier Reef a barrier?

Answer 1

The great barrier reef is being destroyed becuase of global warming, pollution and other factors. Most of it is due to people though.

Further information:

The Great Barrier Reef is not actually almost being destroyed. It does not even have an official listing of endangered: but it is shrinking, and it is unknown by how much.

Climate scientists who subscribe to the theory of anthropogenic global warming (i.e. caused by man's activities) predict that the Great Barrier Reef may lose up to 95% of its coral by the middle of the current century. Although the coastline parallel to the Great Barrier Reef has been settled by Europeans for less then 200 years, these scientists believe that the Reef has been shrinking by 20% every 100 years.

Climate scientists who subscribe to the theory that global warming is cyclical perhaps have a less drastic view, as they believe that the coral will regenerate, as it has done so in the past. Destruction and regeneration is all part of the reef's natural cycle. parts of tye northern Great Barrier Reef that have been damaged during a warming cycle have been found to regenerate after just twelve years.

However, it should be noted that pollution and chemical runoff pose a very real threat to the reef. The water quality of the reef is affected by sediment and nutrients, and 80% of this is caused by cattle grazing on the land adjacent to the reef. Mud and chemical runoff tend to limit the sunlight that reaches the coral, causing it to die off, and they increase the macro-algae, which is a weed.

Tourism is a threat to the reef, as tourist boats damage the delicate framework of the reef; fishing and pollution left behind by visitors also is a threat.

Answer 2

The Great Barrier Reef contains, like many other reefs, its own Eco-cycle per se. The reason that it's so fragile is because the slightest rise in temperatures can make the reef uninhabitable for may of the aquatic creatures there. Since fishes among other inhabitants of the reef are not able to control their body temperature by themselves like mammals, they need the water to be the perfect temp in order for them to live. However, the temp of the water can change due to many things, pollution in the water, global warming, human intervention.

For example, if there was an oil spill (like the one in the Gulf of Mexico thanks to BP) the oil itself will have a temperature that will affect the water around it, but in addition, because crude oil isn't very transparent it will also decrease the amount of sunlight that hits the bottom of the reef and reduce the temp, and very possibly kill the creatures living there. But that is, if the oil coating their bodies haven't poisoned or suffocated them yet. Or the open flame they'd use to burn the oil out of the water hasn't cooked the living creature alive. It's just all around bad news...

Even the slightest change can alter the reef, much like, say, an earthquake. An earthquake in the middle of the ocean can seem to have no consequences to us humans, until it turns into a tidal wave and destroys a city. Then, since the city's in ruins, they can't care for all the injured people, and many die, but there's no place to bury the bodies, so disease spreads, more people die... make sense?

Answer 3

The Great Barrier Reef acts as a barrier because it runs virtually parallel to the Queensland coast for some 2300km. It prevents the rough surf from reaching the shore, creating a sheltered area for sealife. Australia, like many countries, has a huge continental shelf where the water is relatively shallow for about 16km, and then drops off deeply. The barrier is formed here, where the deep water comes up to the shallow water, being conducive to e development of corals, and attracting fish.