So what's the problem?
The greenhouse effect is an essential part of the natural climate system. The problem is that, since the Industrial Revolution, humans have been pumping vast amounts of extra greenhouse gas into the atmosphere.
The main greenhouse gases from human activities are carbon dioxide (CO2) from burning fossil fuels and cutting down forests, and methane.
Nitrous oxide from fertilisers and fossil fuels, and CFCs used in aerosols, fridges and air conditioning also have a warming effect.
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| The main human sources of methane are rubbish dumps, agriculture and livestock farming. |
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