| Many factories produce long-lasting industrial gases that do not occur naturally, yet contribute significantly to the enhanced greenhouse effect and "global warming" that is currently under way. Beside, deforestation also contribute to global warming. Trees use carbon dioxide and give off oxygen in their place, which helps to create the optimal balance of gases in the atmosphere. As more forests are logged for timber or cut down to make way for farming. However, there are fewer trees to perform this critical function. Population growth is another factor in global warming, because as more people use fossil fuels for heat, transportation and manufacturing the level of greenhouse gases continue to increase. As more farming occurs to feed millions of new people, more greenhouse gases enter the atmosphere. |
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