Environment
The Challenge: Air pollution is causing global warming and making our children sick
Greenhouse gasses, such as carbon dioxide, play an important role in the Earth's atmosphere, affecting temperatures by trapping enough solar radiation from escaping back to space to make the planet hospitable for complex life. Changing the composition of atmospheric greenhouse gasses can disrupt Earth's energy equation, potentially causing adverse impacts on human societies, and putting additional pressures on populations of threatened and endangered species.
Since 1880, the concentration of carbon dioxide in our atmosphere has climbed by more than 30%, from 280 parts per million to 370 parts per million. Scientists agree that these increases are a direct result of human activity, primarily from the burning of fossil fuels. Each year, we add an additional 29 billion tons of carbon dioxide to our atmosphere. Humans also add significant amounts of other greenhouse gasses to the atmosphere annually, including methane and chlorofluorocarbons.
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