Everybody Talks about It
2007; Taylor & Francis; Volume: 74; Issue: 6 Linguagem: Inglês
ISSN
1943-4871
Autores Tópico(s)Literature, Film, and Journalism Analysis
ResumoEverybody talks about the weather, but nobody does anything about it. The remark, generally attributed to Mark Twain, comes from a quote by Twain collaborator Charles D. Warner that appeared in the Hartford Courant on August 27, 1897. The comment undoubtedly got a laugh at the time. It was a favorite of my father, who often used it to describe various intractable problems, from traffic congestion to high taxes to under-funded schools. The irony of Twain's joke, of course, is that we were doing something about the weather. In 1897 we were already 150 years into one of the most far-reaching experiments of all time. It goes something like this: Let's see what happens to our weather we release massive amounts of carbon dioxide and other heat-trapping gases into the atmosphere. It is an experiment that continues to this day, as we now dump about 30 gigatons--yes, gigatons!--of carbon dioxide into the atmosphere each year, largely from the burning of fossil fuels (IPCC 2007). Our worldwide petroleum habit currently consumes over 83 million barrels of oil every day, 24.1% of which occurs in the United States (BP 2007). What was a joke in 1897 is less of a laughing matter today. The results of this experiment are seen in news reports on a daily basis: global warming, disappearing glaciers, violent storms, rising sea levels, and other effects possibly related to changes in the atmosphere. The jury is still out on how much of all this can be attributed to anthropogenic causes, but there is little doubt that big changes are afoot on our planet. Just in the past year we seem to have reached a tipping point in the climate change discussion. Maybe it was The Intergovernmental Panel on Climate Change reports documenting changes in climate, or An Inconvenient Truth, the Academy Award-winning documentary film presented by Al Gore, or the recent Green Paper from the European Commission (COM 2007). Perhaps it was the April Supreme Court ruling that authorized the Environmental Protection Agency to regulate carbon dioxide emissions, or this summer's Live Earth concerts, reportedly watched by 2 billion people around the globe. Or maybe it was the striking visual images of melting glaciers and endangered polar bears. For whatever reason, climate change suddenly is big news. In trying to educate my students about the exponential nature of our modification of the atmosphere, I like to point out that atmospheric CO2 levels have increased dramatically, from about 280 ppm to almost 390 ppm, just since the beginning of the industrial revolution in the mid 1700s. I now think this might be a wrongheaded approach. Mention the year 1750 to an average teenager, and it will seem incredibly ancient--you might as well say when dinosaurs roamed the Earth--as all the past is generally relegated to the vast dustbin of history. A better approach might be to discuss how two-thirds of this increase in atmospheric C[O.sub.2] has occurred during their parents' lifetimes (since 1960), and one-third just in their own short lives (since 1990). Even more striking: If current trends continue, the increase in C[O.sub.2] concentration in our students' lifetimes will quadruple the entire change that occurred before they were born. It is an unprecedented experiment in modifying global systems. Articles in this issue of The Science Teacher (TST) show how the weather and climate theme offers a rich opportunity for interdisciplinary inquiry in our science classes. …
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