is the process by which radiation from a planet's atmosphere warms the planet's surface to a temperature above what it would be without this atmosphere.
greenhouse effect
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is a fuel formed by natural processes, such as anaerobic decomposition of buried dead organisms, containing organic molecules originating in ancient photosynthesis that release energy in combustion.
fossil fuels
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is air pollution that reduces visibility.
smog
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is useful energy that is collected from such resources, which are naturally replenished on a human timescale, including carbon neutral sources like sunlight, wind, rain, tides, waves, and geothermal heat.
renewable
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is the long-term heating of Earth's climate system observed since the pre-industrial period (between 1850 and 1900) due to human activities.