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SECTION TEST - ACADEMIC READING
(Time: 60 minutes)

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Passage 1

The Gulf Stream and Global Warming

Labrador and London lie at about the same latitude, but Labrador is frigid and has only 30 miles of paved roads while London is one of the major centers of civilization. Why do two places, equidistant from the Arctic Circle, have such disparate climates? The Gulf Stream that flows by the British Isles makes all the difference: Its warm waters make northwestern Europe so abundant with life that palm trees can actually grow on the southern shores of England.

This life-giving Gulf Stream is warm, salty water, which travels along the surface of the Atlantic Ocean from the Caribbean, along the east coast of the United States, and then veers toward Europe. In the tropics, this water is warmed by the sun and becomes saltier because of the higher rate of evaporation in the heat. The Gulf Stream divides as it travels, but the majority of the stream moves north and east. As it travels past Europe, the Gulf Stream warms the atmosphere, and the prevailing westerly winds bring the warmed air to all of northwestern Europe, making the area suitable for intense agriculture. The Gulf Stream makes it possible for Europe to feed an increasingly large population.

After the Gulf Stream reaches southeast Greenland and western Iceland, much of the heat of the stream is gone, and the colder, denser water then sinks. The bulk of the Gulf Stream is carried down toward the ocean floor into as many as seven large vortices, called chimneys. They suck the Gulf Stream waters down over a mile deep, where the water is then drawn into another dynamic ocean current. Almost 2 miles below the surface, this cold water current flows in reverse, from the north southward. When this cold water nears the equator, it is again pulled up from the bottom of the ocean as the surface water is heated and starts its journey north. This upwelling brings with it minerals and food from the detritus at the bottom of the ocean to refresh food supplies for fish and other marine creatures.

This stream of water—the warm water traveling north along the surface and the cold water traveling south along the floor—has become known as the Great Ocean Conveyor Belt. This flow of ocean currents has been extremely important in regulating the temperature of the globe and in making life possible. These currents in the North Atlantic are part of the Great Conveyor Belt that flows through all the oceans of the world. The least stable section of this global current is in the North Atlantic. The Gulf Stream is the most unstable of all.

Predictions of the effects of global warming on the Gulf Stream are based on computer models, which differ to some extent. But several important facts are known. South of Greenland, there used to be as many as seven chimneys that pulled water from the Gulf Stream down toward the ocean floor. In the last several years, only one remained, and then, in 2007, that one disappeared. The causes for the demise of the chimneys may include the increase in fresh water from glacial melt. In recent winters, glacial melt has released record amounts of fresh water into the oceans. As the North Atlantic waters, including fresh water from rivers as well as the increased amount of glacial melt, mix with the Gulf Stream, the salt water is diluted. Because fresh water is not as dense as salt water, it does not sink, which impairs the natural mechanism for forming the chimneys. As the chimneys have disappeared, the Gulf Stream has slowed. About 30 percent of the water from the Gulf Stream that used to reach Europe travels elsewhere or is lost in the disintegration of the current, a loss of over six million tons of water flow every second. Without a strong Gulf Stream, the slow, cold water of the lower part of the conveyor belt fails to rise, which reduces the circulation of nutrients for marine life. The problem of warming then worsens: As less surface water, which is full of carbon dioxide from the atmosphere, siphons into the depths of the ocean, less carbon dioxide is removed from the atmosphere, thus increasing global warming.

Ocean sediments and glacial cores show that there have been global swings in temperature in the past. The last Ice Age, when much of North America and northern Europe were covered in glaciers 2 miles thick, occurred when the average Temperture dropped about 5 degrees Celsius. That ice age ended about 20,000 years ago. The last “Little Ice Age,” when the average temperature dropped only 1 to 2 degrees Celsius, occurred in the sixteenth and seventeenth centuries, hitting Europe hardest. At that time, the Gulf Stream had slowed to about half its usual rate.

Core samples also show that the changes in temperature have been abrupt, not gradual. There would be little time to prepare for the devastating changes resulting from the weakening of the Gulf Stream. The good news is that in the winters of 2008 and 2009, one of the chimneys off southeastern Greenland suddenly burst into action again, bringing the Gulf Stream waters down deep enough to be caught in the conveyor and to keep the ocean currents in the North Atlantic flowing.

The flow chart below shows a possible effect of global warming on the Gulf Stream. Complete the flow chart using the list of words below.

less salty	colder	warmer
sink	rise	weakened
strengthened	heated	food
thaw	air	form

sink food rise weakened less salty thaw

(1).
(2).
(3).
(4).
(5).
(6).

Passage 2

Food Gamble Divides the Globe

As the millennium draws to a close, the world stands divided on whether the genetically manipulated dietary promises of tomorrow are a scientific triumph or Frankenstein in green. This could be the cue for Australia to leap into the limelight as the world's healthy food provider. But will it?

The unrest about genetically modified (GM) foods began in the mid-nineties when in¬group, educated greenies began very quietly signalling warnings against the work of dedicated and serious scientists in the employ of large biochemical companies. The greenies were seen to have less credibility.

But committed greenies do not give up. The result has been a marketplace revolt against the biochemical giants and their laboratory alteration of the DNA of living organisms to produce high yields as well as resistance to chemicals and disease.

Recently the greenies gained an overwhelming victory in the United Kingdom when two of the world's biggest food manufacturers backed away from the use of genetically modified ingredients.

With Australia's eyes turned firmly towards the United States these days, little note has been taken of the rising anxiety in England and Europe.

A British Consumer Association poll showed that 92 per cent of people wanted GM foods to be labelled and a recent poll by the Daily Record found that 'nine out of 10 shoppers would switch supermarkets to avoid genetically modified foods', some saying they were willing to travel double the usual shopping distance to do so.

Yet here in Australia, floodgates have been open for GM foods and only last week with the closing of the date for applications for approval of GM crops, some 15 new ingredients found their way into consideration by the Australian and New Zealand Food Authority (ANZFA). These include such things as potatoes, soy, canola, corn and sugar beet.

This brings to 23 the number of engineered crops which could be present as ingredients in assorted manufactured foods available in our supermarkets-untested, unassessed and unlabelled.

While the biotechnical corporations which are developing GM products argue the immense benefits that disease resistant, high-cropping and insecticide or pesticide-immune crops may offer the overpopulated world of the future, other scientists, along with environmental groups around the world, protest that these foods are being introduced to the market before their long-term effects have been properly assessed.

The strongest thrust from the environmental lobby is at least for enforced labelling of GM products-since they may be found in all manner of very ordinary mass consumption items from baby foods to cooking oils.

Often food manufacturers don't even know if they are using GM ingredients. The US for example, blends its natural and GM soya beans before export to Australia.

Director of Australia's GeneEthics Network, Bob Phelps, lamented the last-minute flood of applications for approval by ANZFA saying the country had just lost a 'fantastic opportunity' both to keep its foods free of GM ingredients and be one of the countries to which overseas markets could look for all- natural crops.

Commenting on last week's burst of last minute GM crop applications, mainly from American-based biochemical super companies, he said the Government was revealing 'a woeful lack of understanding of the world marketplace.'

'It is the strongest, most sustained and deepest reaction from the marketplace. These big buying consortia are looking to us for no-GM commodities in very large quantities. They are scouring the world for a very large volume and a sustainable supply. If Australia moves in the GM direction, it would be the stupidest thing we could do to our economy. The market is now wide open. It is the greatest opportunity. The global trend is towards healthier foods. It is not only Britain but all of Europe, most recently and, highly vocally Portugal, Italy and Spain as well, expressing the trend towards natural foods. Japan, too. This trend is retail driven. These new consortia have immense retail strength. And yet we don't have the message. This is a pivotal time for Australia. It is no flash in the pan.'

Of course, ANZFA has extremely strict guidelines and there is no question that Australian authorities do not intend to safeguard the population as best they can in the testing of new products.

Things are tracking at various stages,' Peter McMahon, food regulations adviser assures us. 'Europe approached this in a different way to us. We have to acknowledge that in attempting to regulate a new technology, standards have yet to be determined.

Things are quite tentative at the moment. Governments and regulations are catching up with technology.'

However, World Scientists, a group of 14 geneticists, immunologists, biologists, toxipathologists, virologists and agronomists, has called for a moratorium on GM crops and a ban on genome patents.

They have amassed examples of cross- pollination of herbicide-resistant transgenes to wild relative canola and sugar beet plants, 'creating many species of potential super weeds'. Doubts over the safety of transgenic foods follow revelations of animal feeding experiments such as the headliner rats in Scotland whose diet of GM potato caused internal bleeding. The Greens in Europe have lobbied the European Parliament about sustaining a ban on GM hormones injected into cows to boost milk yields. Cows have been observed to suffer increased foot problems, mastitis, injection site swellings and, with an increase in levels of insulin-like Growth Factor (which occurs naturally in milk), a suspected increased risk of prostate and breast cancer in humans.

As one environmentalist put it: 'Genetic pollution cannot be recalled.'

Complete the summary of the reading passage below. Choose your answers from the box below. NB: There are more words/phrases than you will need to fill the gaps. You may use a word or phrase more than once if you wish.

consumption	increased supply
England and Europe	labelled
growth	yields
GM-free	numbers
Australia and New Zealand	examples

labelled increased supply examples England and Europe / Europe and England yields

SUMMARY

Concerns about genetically modified (GM) foods began in the nineties with a small group of environmentalists. Over time increasing numbers of people have become concerned about foods genetically modified to increase and decrease disease.

Concern has been greatest in with the US and Australia continuing to widen the number of GM products regardless of the lack of evaluation and labelling. The environmentalists at least want products with GM ingredients to be .

Bob Phelps of GeneEthics believes Australia is giving up a fantastic opportunity to not only have GM-free food for domestic markets but also be able to supply a world market in which demand for of GM-free food is growing.

While the ANZFA are in the process of testing and regulating GM foods one group called World Scientists believe there are enough of side-effects in animals eating GM food that all GM crops should be immediately banned while extensive testing is carried out.

Passage 3

The Braille System

About 200 years ago, a curious three-year-old boy playing in his father’s shop had an accident that ended up changing the lives of hundreds of thousands of people. The little boy was Louis Braille, and his father was a harness maker in Coupvray, France, a small town near Paris. Louis poked his eye with one of the sharp tools on his father’s workbench. The injury and the ensuing infection, which spread through both eyes, caused him to lose his vision. Only a dozen years later, at the age of fifteen, Braille developed a system of raised dots on paper that made it possible for blind people to read and write. While he was not the first person to toy with the idea of tactile reading—that is, reading by feeling shapes on a flat surface—his system surpassed others thanks to its simplicity, ease of use, and adaptability.

During the first few years after his accident, Braille attended a local school with sighted children, where he learned by the only means available to him—listening and memorizing, He was a gifted student and at the age of ten earned a scholarship to attend the Royal Institution for Blind Youth in Paris. He later became a teacher at the Institution and remained there until his death in 1852 at the age of forty-three. The Institution relied largely on oral instruction, but pupils had access to a few books specially designed for blind students by Valentin Hauy, the school’s founder. Haiiy had developed a method for pressing shapes of letters onto wet paper and then letting them dry, providing pages with raised characters that students could “read” by running their fingertips across the thick paper. The books were big and cumbersome and took a long time to produce—and to read. In addition, they addressed only part of the blind students’ communication dilemma—the ability to read. For full literacy, students also needed to be able to write.

A man named Charles Barbier, who had invented a system known as night writing for soldiers to send messages in the dark, provided the inspiration Braille needed for his reading method. Barbier visited the Royal Institution for Blind Youth in 1821 to demonstrate his technique, which used rectangular cells with raised dots. The cells, thirty-six in all, represented sounds rather than individual letters of the alphabet and consisted of a template of twelve dots in six rows of two. Braille saw the system’s benefits right away and then zeroed in on its drawbacks. He thought it should be based on the alphabet—the way sighted people read—and not on phonetics. It also needed a way to designate punctuation marks, accents, numbers, and other symbols; and, for the user to be able to read with ease, a cell had to be small enough to fit beneath one’s fingertip.

For the next three years, Braille fine-tuned his system and in 1824 came up with a version that worked to his satisfaction: a six-dot cell (three rows of two) that allowed for sixty-three possible combinations of dots, enough for all twenty-six letters of the Roman alphabet plus accents, capital letters, punctuation marks, and numbers. For example, a cell with one dot at the top left (position one) represents the letter a, whereas a cell with one dot at the bottom right (position six) means the next symbol is a capital letter. The numbers zero to nine are coded the same as the letters a to j , except they are preceded by a cell with dots in positions three through six (bottom left dot and all three dots in the right column). Users could read an individual cell with a single touch of the fingertip, and they scanned dots from left to right as in normal reading. What’s more, the Braille system made it possible to write by punching dots into paper (from right to left because the reverse side is read).

Originally, Braille symbols were written with a slate and stylus—the equivalent of paper-and pencil writing, using the slate to hold the paper and the stylus to prick holes in it. In 1892, a Braille writing machine was invented; used like a typewriter, it has six keys and a space bar. Today, writing Braille is no more difficult or time-consuming than producing a printed document. You need only to hook up a standard computer to a machine that will emboss the text in Braille. Braille’s fellow students quickly learned his system; for the first time, they could take notes in class and write papers, not to mention pass notes back and forth to one another. Yet the system was not widely used in Braille’s lifetime. It did not become the official communication system for blind people in France until 1854, two years after he died.

The system remains in use today, only slightly altered from the original version. It has incorporated symbols for math, science, and music and has been adapted to dozens of languages, including many with non-Roman alphabets, such as Chinese and Japanese. Braille symbols often show up in public places, such as on elevator buttons, and their helpfulness in labeling household items like canned goods is undisputed. Nevertheless, knowledge of Braille has declined in recent years as technology has provided innovations, such as recorded books and computers with synthetic speech, that make it less necessary to read the old-fashioned way. Many now deem Braille an obsolete system, but its devotees still consider it a form of literacy as basic as the three R’s.

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