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Show discussion on global climate, the question is not 4 i a lS tf !S but Will it change? How will it change and over what period of time? Scientists have long been ' aware through a variety of methods that load, regional and global climatic changes have taken (dace, but It hasnt been until relatively recently that man discovered that his activities may lead to major changes In weather patterns. a There are currently three mqjor views as to what we can expect 'in terms of future climate changes: (1) the climate will get colder as we move into a new great ice age; (2) the world's climate will get warmer primarily because of human activities that counteract the natucooral and human-caused ling trends; and (3) scientists dont have enough knowledge and evidence to explain either short-teror long-terswings in the worlds climatic patterns. Hie second of the above scenarios is currently acm m cepted by the majority of scientists as to be the most accurate. It is now believed that .the earth is indeed heating up. The Greenhouse Effect fcThe greenhouse effect results when carbon dioxide, water and other gases in the atmosphere allow the penetration of the suns ultraviolet radiation to the earth but then absorb the infrared (heat) waves that are radiated from the earth back to the sky. Most people are familiar with the greenhouse effect when they notice that the inside of their car remains warm in the winter although outside temperatures are very cold. The windshield of the ' car allows for the penetration of the suns UV light which is converted to infrared or heat rays when striking the seats and dashboard. The heat escapes at a much dower rate through the glass and thus the car warms. This "effect is most familiar when one uses a greenhouse and gets its name . from that source. Greenhouse Effect Protects Us The atmosphere around the earth acts much like the glass of a greenhouse forming a kind of thermal blanket around the planet. The greenhouse effect protects us from the very icold - . temperatures that are found on planets that lack an atmosphere. Hie moon is not a planet but is V i. approximately the same distance from the sun as we are. Because it lacks an atomosphere, its surface is very cold. Farmers and those that have fruit trees have long known that tree buds are more easily frozen in the early spring when the sky is dear (heat escapes) as opposed to cloudy nights where the clouds tend to insulate from heat loss. factual evidence. On the positive side, wanner temperatures would result in longer growing seasons and mildW winters which It has been estimated that the average global would decrease fuel bills. atmospheric temperature today is about 18 degrees F higher than it would be without any carbon dioxide or water in the atmosphere. Thus carbon dioxide and water. vapor seem to be two gases that strongly affect the average temperature of our atmosphere. What sort of activities do humans conduct that -- change the atmosphere? Because of the large amount of water vapor and its rapid recycling, humans can do very little to upset the average water concentration in the atmosphere. However, the relatively small concentration of carbon dioxide (about 0.03 percent) can be increased significantly as the earths fossil fuels are burned and as forests are cleared. When coal, oil, natural gas, wood or any other carbon containing are burned, compounds carbon dioxide, water and heat are released into the air. As the level of the water increases, the mean global temperature should rise. Earth Temperatures ' ' are Hiring . ' Measurements since 1958 and estimates of past values show that the average global concentrations of water have been increasing since the beginning of the industrial revolution (1880s) and have shown an even sharper rise since 1958. According to the greenhouse model, the average global temperature should have increased by one-ha- degrees F between lf 1880 and 1975. Assuming the continued increase in the burning of fossil fuels and deforestation with all other factors the same, the increase in water could cause an average increase in the atmospheric temperature from about 0.5 to 1.0 degrees F and by 2150 the temperature could rise 5 degrees F. Perhaps even more significant, the temperature rise in the global regions is expected to be three to five times larger than the average global increase. What Are The Side Effects? The predicted increase in atmospheric temperature could occur more rapidly or ' more slowly than predicted depending on a host of other factors that come into play when studying the model presented. Many people ask Why worry about this? What effect can a slight' ly warmer temperature The increased water would undoubtably increase photosynthesis and crop yields by at least some amount. However, the beneficial affects are believed to be far outweighed by the harmful affects. A major effect of slight warming would be to shift crop growing regions. The grainbelt of the US would be shifted north to the poorer Canadian soils offsetting the beneficial effects increased crop production. Fish populations might also move northward shifting the fishing industry to Greenland instead of Nova Scotia. While some nations would benefit, others would be hurt. Hie effects at the poles would be even more drastic. Sea levels could rise anywhere from three to fifteen feet as polar ice ' melted. This process would be very slow but would endanger many of our coastal cities. The ultimate effect on the environment of course is difficult to predict. A change in mean global temperature would have many se all plant is important, however, to note that science currently does not have all of the answers. "We cant even be sure that the biosphere wont absorb any excess water thus leaving essentially no change in the environment, said Science teacher Randy Merrill. What we can do is continue to study global climate changes, gather data and be prepared to show flexibility if and when our weather change. Is it getting warmer on earth? Will the polar ice caps melt? The Green House effect is causing some earth TEMPERATURES RISE temperature changes. Hasty Pawn Shop & Hasty Furniture Have Teamed Up To Bring You Tremendous Savings! Pre-Seas- on 20 OFF EVERYTHING IN THE STORE! , Friday and Saturday ONLY Vernal 95 So. Vernal Avenue WERE READY FOR CHRISTMAS! - More! Shop Onr Store ForJJales AndEnds Sale Wednesday, 4-- have? Of oourse we can only at the ultimate affects but most of the guess are backed by ' Fashions (Galois MAIN STREET ROOSEVELT 722-99- 87 . |