October 2, 2012 Great Barrier Reef is Shrinking

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1 In News Focus #17, we head to the Great Barrier Reef off the east coast of Australia. The 2,000-kilometer-long reef ecosystem, the center-piece of a multi-billion-dollar tourism industry, is under threat. Scientists have been studying data from more than 200 individual coral reefs off the coast. They claim that the Great Barrier Reef has shrunk by more than half in the last 27 years. The decline is due to tropical storms, global warming and a type of starfish that feeds on the coral. The scientists say that the speed of decline is very worrying. If you are interested in finding out more, then click here. October 2, 2012 Great Barrier Reef is Shrinking In a new study, scientists claim that Australia s iconic Great Barrier Reef has shrunk by more than half over the past 27 years. The reef, which has been closely watched since 1985, has fallen victim to tropical storms, global warming and a plague of starfish. The speed of decline suggests that coral cover could fall to just 5% within the next ten years. Scientists from the Australian Institute of Marine Science (AIMS) have stated that the rapidity of the decline is staggering. It is unprecedented anywhere in the world, says Chief researcher John Gunn: We re looking at the changes that have taken place over one generation of coral, and we re seeing a 50% decline. While there has been an overall trend of coral depletion since the 1980s, the rate of loss in the last five years is dramatic. The AIMS team point to three main reasons for the loss. The number one short-term factor is severe storms in the region, with researchers estimating that 48% of the coral has been destroyed by these storms. Since extensive studies began in 1985 there have been 34 tropical cyclones that have disturbed the seabed and torn off the fragile coral structures that form the reefs. A further 42% of the damage is believed to be caused by the crown-of-thorns starfish. These creatures feed directly on coral, and have undergone a population spike in recent years. The remaining 10% of damage is attributed to coral bleaching which happens when water temperatures rise as a side effect of global warming. Ordinarily, reefs can recover within 10 to 20 years from storms, bleachings or starfish attacks but increased levels of carbon dioxide (CO 2 ) in the atmosphere raise the acidity levels of the water, which makes it much harder for coral to synthesize the calcium carbonate (CaCO 3 ) structures that build a thriving reef. The authors of the new study have pointed to the tens of thousands of species associated with tropical coral reefs that will be affected by the shrinking reefs. However, in addition to the environmental impact, there are concerns for the tourist industry. The Great Barrier Reef coastline currently enjoys a multibillion dollar tourist trade, much of which is focused on the unique natural beauty of the huge reef.

2 John Gunn has emphasized that while the main issues facing the reef are difficult to deal with, there are measures that can be taken to help the coral grow back. The rapid increase in starfish population is probably caused by agricultural fertilizers carried into the sea by inland rivers. Gunn believes that if this pollution can be monitored and controlled, then the reefs may recover more successfully. [A] READING CHECK Are these sentences correct (C) or incorrect (I)? 1. Scientists have been carefully watching the Great Barrier Reef since Their research shows that the reef is now 20% smaller than it was 27 years ago. 3. There are three reasons for the reduction in the amount of coral. 4. Coral reefs are declining at the same fast rate around the world. 5. Strong storms, or cyclones, are the single biggest problem for the Great Barrier reef. 6. Another major problem is a type of starfish that eats the coral. 7. A third problem is coral bleaching caused by increased levels of fertilizers in the water. 8. Not only is the shrinking reef an environmental issue, it could also impact on the amount of money that Australia makes from the tourist trade. 9. John Gunn is confident that his scientists can find a solution to coral bleaching. 10. John Gunn wants to increase the amount of agricultural fertilizers running into the sea in an attempt to restrict the starfish population.

3 [B] WORD FOCUS Fill in the blanks using the correct words below. In a new study, scientists claim that Australia s (1) Great Barrier Reef has shrunk by more than half over the past 27 years. The reef, which has been closely watched since 1985, has fallen (2) to tropical storms, global warming and a (3) of starfish. The speed of decline suggests that coral cover could fall to just 5% within the next ten years. Scientists from the Australian Institute of Marine Science (AIMS) have stated that the rapidity of the decline is (4). It is (5) anywhere in the world, says Chief researcher John Gunn: We re looking at the changes that have taken place over one generation of coral, and we re seeing a 50% decline. While there has been an overall trend of coral (6) since the 1980s, the rate of loss in the last five years is dramatic. The AIMS team point to three main reasons for the loss. The number one short-term factor is severe storms in the region, with researchers estimating that 48% of the coral has been destroyed by these storms. Since extensive studies began in 1985 there have been 34 tropical cyclones that have disturbed the seabed and torn off the fragile coral structures that form the reefs. A further 42% of the damage is believed to be caused by the crown-of-thorns starfish. These creatures feed directly on coral, and have undergone a population (7) in recent years. The remaining 10% of damage is (8) to coral bleaching which happens when water temperatures rise as a side effect of global warming. Ordinarily, reefs can recover within 10 to 20 years from storms, bleachings or starfish attacks but increased levels of carbon dioxide (CO 2 ) in the atmosphere raise the acidity levels of the water, which makes it much harder for coral to synthesize the calcium carbonate structures that build a (9) reef. The authors of the new study have pointed to the tens of thousands of species associated with tropical coral reefs that will be affected by the (10) reefs. However, in addition to the environmental impact, there are concerns for the tourist industry. The Great Barrier Reef coastline currently enjoys a multi-billion dollar tourist trade, much of which is focused on the unique natural beauty of the huge reef. John Gunn has emphasized that while the main issues facing the reef are difficult to deal with, there are measures that can be taken to help the coral grow back. The rapid increase in starfish population is probably caused by agricultural fertilizers carried into the sea by inland rivers. Gunn believes that if this pollution can be monitored and controlled, then the reefs may recover more successfully. 1 (a) isolated (b) iconic (c) inaccessible 2 (a) victim (b) violent (c) viable 3 (a) plague (b) pest (c) plaque

4 4 (a) slanting (b) stammering (c) staggering 5 (a) unpredictable (b) unprecedented (c) unprepared 6 (a) detection (b) depletion (c) deletion 7 (a) spear (b) slump (c) spike 8 (a) attributed (b) afflicted (c) attested 9 (a) throbbing (b) thriving (c) flourish 10 (a) minimize (b) expanding (c) shrinking [C] KEY PHRASES Complete these key phrases by matching words in column A and B. column A column B 1 Scientists claim that the reef has shrunk a raise the acidity levels of the water. 2 The reef has fallen victim to tropical storms and b then the reefs may recover more successfully. 3 The AIMS team point to c to be caused by the crown-ofthorns starfish. 4 Since extensive studies began d there are measures that can be taken to help the coral grow back. 5 A further 42% of the damage is believed e three main reasons for the coral depletion. 6 Increased levels of carbon dioxide (CO 2 ) in the atmosphere 7 While the main issues facing the reef are difficult to deal with, 8 If this pollution can be monitored and controlled, f there have been 34 tropical cyclones that have disturbed the seabed. g by more than half over the past 27 years. h a plague of starfish. [D] SUMMARY Arrange the words in the correct order. 1. Scientists believe that the Great Barrier Reef is [rate / a / shrinking / dramatic / at]. 2. The reef has [victim / fallen / storms / to / tropical], global warming and coraleating starfish. 3. The speed at which the coral is being [anywhere / unprecedented / depleted / in / is] the world. 4. Severe storms in the [have / region / coral / fragile / torn] structures off the seabed. 5. A staggering 42% of the [creatures / to / damage / is /attributed] that feed on coral. 6. Global warming has [higher / led / temperatures / to / water]that in turn have led to coral bleaching. 7. Ordinarily, [by / reefs / synthesizing / can / re-grow], or building, calcium carbonate structures. 8. Unfortunately, the increased acidity of the seawater [for / it / coral / harder / makes] to rebuild. 9. The successful [may / affected / tourist / industry / be] if the huge reef continues to shrink. 10. There are limited measures that can be [help / the / taken / coral / to] re-grow.

5 Answers Technical notes: 1: coral bleaching When corals are stressed by changes in conditions such as temperature or light, they expel the symbiotic algae living in their tissues, causing them to turn completely white. This does not necessarily kill them, but they remain very fragile and vulnerable. 2: agricultural fertilizers encourage the growth of starfish larvae. [A] READING CHECK Are these sentences correct (C) or incorrect (I)? 1. Scientists have been carefully watching the Great Barrier Reef since (C) 2. Their research shows that the reef is now 20% smaller than it was 27 years ago. (I) [The new study shows that the coral has declined by more than half (over 50%).] 3. There are three reasons for the reduction in the amount of coral. (C) [The three reasons are: tropical storms, global warming, starfish.] 4. Coral reefs are declining at the same fast rate around the world. (I) [ It [the decline] is unprecedented anywhere in the world, says Chief researcher John Gunn.] 5. Strong storms, or cyclones, are the single biggest problem for the Great Barrier reef. (C) [They cause almost half of the damage, (48%).] 6. Another major problem is a type of starfish that eats the coral. (C) 7. A third problem is coral bleaching caused by increased levels of fertilizers in the water. (I) [Coral bleaching is caused by changes in water temperature.] 8. Not only is the shrinking reef an environmental issue, it could also impact on the amount of money that Australia makes from the tourist trade. (C) [The Great Barrier Reef generates billions of Australian dollars in tourism.] 9. John Gunn is confident that his scientists can find a solution to coral bleaching. (I) [He emphasizes that it is difficult to deal with the main issues, such as bleaching.] 10. John Gunn wants to increase the amount of agricultural fertilizers running into the sea in an attempt to restrict the starfish population. (I) [He wants to limit/restrict the amount of fertilizers running into the sea.] [B] WORD FOCUS Fill in the blanks using the correct words below. 1 (a) isolated (b) iconic [= famous] (c) inaccessible 2 (a) victim [= to fall (b) violent (c) viable victim to (X)] 3 (a) plague [ = appearance of something in large numbers] (b) pest (c) plaque [= sign on a wall] 4 (a) slanting (b) stammering (c) staggering [= amazing] 5 (a) unpredictable (b) unprecedented [= not (c) unprepared

6 seen before] 6 (a) detection (b) depletion [ = (c) deletion reduction] 7 (a) spear (b) slump (c) spike [sudden jump / peak] 8 (a) attributed [= (b) afflicted [affected by (c) attested assigned to] (X)] 9 (a) throbbing [= (b) thriving [ = (c) flourish beating] flourishing] 10 (a) minimize (b) expanding (c) shrinking [C] KEY PHRASES Complete these key phrases by matching words in column A and B. column A column B 1 Scientists claim that the reef has shrunk g by more than half over the past 27 years. 2 The reef has fallen victim to tropical h a plague of starfish. storms and 3 The AIMS team point to e three main reasons for the coral depletion. 4 Since extensive studies began f there have been 34 tropical cyclones that have disturbed the seabed. 5 A further 42% of the damage is believed c to be caused by the crown-of-thorns starfish. 6 Increased levels of carbon dioxide a raise the acidity levels of the water. (CO 2 ) in the atmosphere 7 While the main issues facing the reef are difficult to deal with, d there are measures that can be taken to help the coral grow back. 8 If this pollution can be monitored and controlled, h then the reefs may recover more successfully. [D] SUMMARY Arrange the words in the correct order. 1. Scientists believe that the Great Barrier Reef is [shrinking at a dramatic rate]. 2. The reef has [fallen victim to tropical storms], global warming and coral-eating starfish. 3. The speed at which the coral is being [depleted is unprecedented anywhere in] the world. 4. Severe storms in the [region have torn fragile coral] structures off the seabed. 5. A staggering 42% of the [damage is attributed to creatures] that feed on coral. 6. Global warming has [led to higher water temperatures] that in turn have led to coral bleaching. 7. Ordinarily, [reefs can re-grow by synthesizing], or building, calcium carbonate structures. 8. Unfortunately, the increased acidity of the seawater [makes it harder for coral] to rebuild. 9. The successful [tourist industry may be affected] if the huge reef continues to shrink. 10. There are limited measures that can be [taken to help the coral] re-grow.

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