What is the effect of the heat produced by the population of the world on average temperatures?

Question

Thera are 4+ billion poeple on earth now, if each one gives off an average of 400 watts, thats 1.6 billion killowatts !!!! ????

Answer 1

It would not be measurable.  You might get warmer in a crowded unventilated room but there aren't enough people to change global temperatures.  The CO2 exhaled from all the people might warm temps something like a 1/10 of a degree but I don't think we can ask them to stop breathing and it all goes back into plants anyway so it is not like it just keeps building up.

Answer 2

effectively zero.

plants take in energy to make glucose. this is in the form of light. if this light was not used for photosynthesis it would just heat up the earth. so when humans use glucose and release energy we are just returning it to the cycle.