|MadSci Network: Physics|
Yes, but at the same time, heat is constantly leaving the earth by radiating out into space. The amount of heat created by the friction of your movements is insignificant compared to the amount of heat arriving constantly from the sun. It is the sun's heat that is the key factor in balancing the incoming and outgoing heat energy to prevent global warming. As the greenhouse effect worsens, more heat gets trapped in the Earth's atmosphere, and the temperature rises. This includes the heat from your movements, but still, the heat from the sun is what really makes the difference.
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