Originally, Arctic contamination was largely blamed on chemical leaks, and these leaks were thought to be “small and localized.” The consensus now is that pollutants from around the world are being carried north by rivers, ocean currents, and atmospheric circulation. Due to extreme conditions in the Arctic, including reduced sunlight, extensive ice cover and cold temperatures, contaminants break down much more slowly than in warmer climates. Contaminants can also become highly concentrated due to their significantly lengthened life span in the Arctic.
Problems of spring run-off into coastal waters during the growth period of marine life are of critical concern. Spring algae blooms easily, absorbing the concentrated contaminants released by spring melting. These algae are in turn eaten by zooplankton and a wide variety of marine life. The accumulation of these contaminants increases with each step of the food chain or web and can potentially affect northerners who eat marine mammals near the top of the food chain. Pollutants respect no borders; transboundary pollution is the movement of contaminants across political borders, whether by air, rivers, or ocean currents. The eight circumpolar nations, led by the Finnish Initiative of 1989, established the Arctic Environmental Protection Strategy (AEPS) in which participants have agreed to develop an Arctic Monitoring and Assessment Program (AMAP). AMAP establishes an international scientific network to monitor the current condition of the Arctic with respect to specific contaminants. This monitoring program is extremely important because it will give a scientific basis for understanding the scope of the problem.
In the 1950’s, pilots traveling on weather reconnaissance flights in the Canadian high Arctic reported seeing bands of haze in the springtime in the Arctic region. It was during this time that the term “Arctic haze” was first used, referring to this smog of unknown origin. But it was not until 1972, that Dr. Glenn Shaw of the Geophysical Institute at the University of Alaska first put forth ideas of the nature and long-range origin of Arctic haze. The idea that the source was long range was very difficult for many to support. Each winter, cold, dense air settles over the Arctic. In the darkness, the Arctic seems to become more and more polluted by a buildup of mid-latitude emissions from fossil fuel combustion, smelting and other industrial processes. By late winter, the Arctic is covered by a layer of this haze the size of the continent of Africa. When the spring light arrives in the Arctic, there is a smog-like haze, which makes the region, at times, looks like pollution over such cities as Los Angeles.
This polluted air is a well-known and well-characterized feature of the late winter Arctic environment. In the North American Arctic, episodes of brown or black snow have been traced to continental storm tracks that deliver gaseous and particulate-associated contaminants from Asian deserts and agricultural areas. It is now known that the contaminants originate largely from Europe and Asia.
Arctic haze has been studied most extensively in Point Barrow, Alaska, across the Canadian Arctic and in Svalbard (Norway). Evidence from ice cores drilled from the ice sheet of Greenland indicates that these haze particles were not always present in the Arctic, but began to appear only in the last century. The Arctic haze particles appear to be similar to smog particles observed in industrial areas farther south, consisting mostly of sulfates mixed with particles of carbon. It is believed the particles are formed when gaseous sulfur dioxide produced by burning sulfur-bearing coal is irradiated by sunlight and oxidized to sulfate, a process catalyzed by trace elements in the air. These sulfate particles or droplets of sulfuric acid quickly capture the carbon particles, which are also floating in the air. Pure sulfate particles or droplets are colourless, so it is believed the darkness of the haze is caused by the mixed-in carbon particles.
The impact of the haze on Arctic ecosystems, as well as the global environment, has not been adequately researched. The pollutants have only been studied in their aerosol form over the Arctic. However, little is known about what eventually happens to them. It is known that they are removed somehow. There is a good degree of likelihood that the contaminants end up in the ocean, likely into the North Atlantic, the Norwegian Sea and possibly the Bering Sea — all three very importantfisheries.
Currently, the major issue among researchers is to understand the impact of Arctic haze on global climate change. The contaminants absorb sunlight and, in turn, heat up the atmosphere. The global impact of this is currently unknown but the implications are quite powerful.
Questions 15 - 27
Read the passage about alternative farming methods in Oregon again and look at the statements below.
In boxes 15 - 21 on your answer sheet write:
TRUE if the statement is true
FALSE if the statement is false
NOT GIVEN if the information is not given in the advertisement
15 Industry in the Arctic has increased over the last 20 years.
16 Arctic conditions mean that the break down of pollutants is much accelerated
17 Pollution absorbed by arctic algae can eventually affect humans.
18 The AEPS has set up scientific stations in the Arctic to monitor pollution.
19 Arctic pollution can sometimes resemble US urban pollution.
20 Evidence that this smog has only occurred in the 20th Century has been found in the ice on the polar ice cap.
21 Research has shown that aerosol arctic pollutants remain the air indefinitely.
Questions 22 – 27
Complete the summary relating to Arctic Haze below.
Choose your answers from the box below the summary and write them in boxes 22 – 27 on your answer sheet.
NB There are more words than spaces, so you will not use them at all.
......................... that the origins of spring, arctic haze, Theories
first seen over the ice cap... (eg)
___________ that the origins of spring, arctic haze, first seen over the ice cap in the 1950s, came from far away were at first not (22) _________. This haze is a smog formed in the dark, arctic winter by pollution delivered to the Arctic by storms (23) _____________ in Europe and Asia. It is known to be a recent phenomenon as proof from (24) ____________ shows it only starting to occur in the 20th Century. The smog consists of sulphates and carbon, the latter creating the (25) __________ of the haze. Due to lack of research, the final destination of the pollution is unknown but it probably ends up in the (26) ___________ and therefore into the food chain. Scientists are presently more worried about the (27) _____________ effect it has on climate change.
|burning terrible ice cores valid certain
originating sea destroying theories unknown
agriculture decided bird life dissipating accepted
gases darkness air density
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