Carbon dioxide, a greenhouse gas, is the main pollutant that is warming Earth. Even though all living things emit carbon dioxide when they breathe, carbon dioxide is widely considered to be a pollutant when associated with cars, planes, power plants, and other human activities that involve the burning of fossil fuels such as gasoline and natural gas. Just in the past 150 years, such activities have pumped enough carbon dioxide into the atmosphere to raise its levels higher than they have been for hundreds of thousands of years.
Other greenhouse gases include methane — which comes from such sources as swamps and gas emitted by livestock — and chlorofluorocarbons (CFCs), which were used in refrigerants and aerosol propellants until they were banned because of their deteriorating effect on Earth’s ozone layer.
Another pollutant associated with climate change is sulfur dioxide, a component of smog. Sulfur dioxide and closely related chemicals are known primarily as a cause of acid rain. But they also reflect light when released in the atmosphere, which keeps sunlight out and causes Earth to cool. Volcanic eruptions can spew massive amounts of sulfur dioxide into the atmosphere, sometime causing cooling that lasts for year.
If we continue our thoughtless abuse of these dangerous gases, we could all be on our way to oblivion.
Posted by: Mariel E. Madlambayan
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