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Question About Global Warming Science

Prometheus

Acolyte of Víðarr
Joined
Nov 14, 2007
Messages
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I'm curious whether any attempt has been made to account for the aggregate heat generated by burning fossil fuels. As I understand it, FFs represent millions of years' worth of solar energy, captured and stored in organic material. By burning them so quickly, aren't we effectively multiplying/adding to the amount of solar heat that reaches the Earth's surface? Is this even measurable?
 
The amount of heat we get from combining the carbon we dig out of the ground with oxygen in the atmosphere is minuscule compared to the amount of heat that comes in from the Sun, or the (nearly equal) amount that is radiated from the Earth as a result of that absorption. We really aren't using a lot of power yet. The difference between income and outgo that is made by the CO2 that results is far more, simply because the incoming and outgoing energy is so astronomically huge.
 
Seconded. Note that the vast majority of heat released by these processes is transferred to rivers, ultimately making its way to the ocean. A cloudy day over the ocean would have a greater effect.

To put it in perspective, a typical, 1200 MWe nuke plant generates about 3500 MWt, so it throws away 2300 MWt. Let's round up and say 2500. At about 100 nuclear plants in the USA, and 20% of US power coming from nuclear, and the US making up about 25% of the worlds GDP, that gives you 5 million megawatts being thrown away. I know this isn't quite precise, but it should be within an order of magnitude.

The solar energy constant at Earth's orbit is 430 BTU/hr/square foot, or 126 watts/ft 2. Give that Earth is 8000 miles in diameter, earth sucks down 1.76 x 10^11 megawatts of solar energy. That's 5 orders of magnitude of difference. Granted some of that is reflected back, and there are other effects to consider, but not 5 orders of magnitude of effects.

Thus, we can say that the waste heat generated by commercial power is less than a drop in the bucket.
 
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