Living the 'Green' Life
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Why is the climate changing? What causes global warming? What creates the so-called greenhouse effect?
The answers to these questions all have to do with the chemical composition of the Earth's atmosphere. The atmosphere around us is made up of gases. Some of these gases function like the panes of a greenhouse: they let some radiation from the sun in but also retain heat in the atmosphere, that is: they don't let all radiation back out. As a result of this natural effect, it is warmer on Earth than it would be without these heat-trapping gases. Human contributions of certain gases to the atmosphere have increased this greenhouse effect. Carbon dioxide (CO2) is one of those heat-trapping (greenhouse) gases that have increased significantly in atmospheric concentration since pre-industrial times and thus has raised the greatest concern. But several others contribute significantly to the warming of the lower part of the atmosphere, such as · methane (CH4) · nitrous oxide (N2O) · ozone (O3) · halocarbons The combined warming effect (positive radiative forcing) from these other trace gases is approximately equal to that of CO2. In addition, there are small particles (aerosols) that can directly or indirectly help cool the atmosphere (negative radiative forcing). Examples include · sulphates (e.g., produced by burning coal) · volcanic dust. Some of these gases and aerosols are very effective in trapping heat or blocking incoming radiation, but are relatively quickly removed from the atmosphere. Others can trap less heat, but stay in the atmosphere longer. The combination of these factors determines what scientists call the direct Global Warming Potential of an emitted compound -- a measure the IPCC has devised to show "the possible warming effect on the surface-troposphere system arising from the emission of each gas." [Source: Union of Concerned Scientists] Why should I care that earth is warming up? How is it going to affect me? Climate change is about us: our homes, our lives, our world. It is our responsibility to do something about it. However terrifying, environmental catastrophes have historically been essentially national or regional. 'Global warming is exactly that - global' The impact of the Chernobyl nuclear disaster, for example, was felt far beyond the borders of Ukraine. Hundreds of British farms are still believed to be contaminated with radioactive material - mostly Caesium 137 - from Chernobyl. But it was still not a planet-wide catastrophe. Global warming is different. Global warming is exactly that - global. This, of course, also means it is local everywhere - the very nature of atmospheric gases and the water in our oceans makes it so. [Source: Worldwide Fund for Nature] Do I contribute to global warming by the choices I make? Carbon dioxide (CO2) emissions are one of the main causes of global warming. Unfortunately we all produce CO2: by driving cars, boiling the kettle, watching TV, even going on holiday. The good news is you can do something about it. Most people don't realize that electricity is one of the biggest producers of CO2. That's because it's produced by burning fossil fuels. So each time you switch on the TV or cook a meal, you're contributing to global warming. You could switch to renewables and cut that CO2 to zero. Click here for more tips. [Source: Future Forests] How do I switch to a low carbon lifestyle? Climate scientists estimate the Earth can cope with 4 billion tons of carbon released from burning fossil fuels (such as petrol in a car engine) because the Earth has natural systems in place – such as trees and oceans – that can absorb, or ‘clean up’, excess carbon dioxide. That means (if carbon emissions are shared out equally) each person on Earth can give off around 2.5 tons of carbon dioxide, per year. However, a person living a typical modern western lifestyle has a carbon dioxide footprint of around 10 tons per year, four times greater than their fair share. And that’s without including any flights or shipping! Switching off your TV, video, DVD or stereo at the set stops the extra 10-60% electricity used by being on standby. If just 10 households switched off their TV sets properly, 1 ton of carbon would be saved. Reduce your driving emissions by avoiding hard acceleration and keeping your speed down. [Source: Center for Alternative Technology and Future Forests] Greenhouse gases are inevitable products of industrialization. Businesses cannot help but pollute, is it possible to eliminate greenhouse gases? There are a number of ways that corporations as well as other large institutions like hospitals, universities, and government agencies can curb the amount of carbon dioxide and other greenhouse gases they emit into the atmosphere. At the production and manufacturing level, for example, companies can save energy and other resources by designing products with fewer materials and less packaging, and by making new products out of recycled materials. Through their formal purchasing channels, institutions can commit to using energy-efficient office equipment or fixtures, and can use recycled materials such as paper, which require less energy to produce. Some businesses have already committed to reducing their greenhouse gas emissions by purchasing energy from renewable sources, and by choosing fleets of low emission vehicles. Businesses can also provide benefits that encourage employees to use public transportation, and facilitate telecommuting. (For more examples, see www.worldwatch.org/press/news/2003/07/22/.) Individuals can play an important role in encouraging corporations to reduce their greenhouse gas emissions by patronizing businesses that have committed to polluting less, filing and voting on shareholder resolutions, or participating in letter-writing campaigns or boycotts. [Source: World Watch Institute] |
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