Visit a power plant in winter and you can literally see the heat
pouring out of it as the hot air of its exhaust mixes unevenly
with the cold air around it. It's easy to convince yourself that
the mere burning of fossil fuels, rather than the greenhouse
gasses the burning releases, could be altering the climate. But
the total energy released is rather small on a global scale, so
researchers have largely treated it as a rounding error. A new
paper suggests that, although power generation doesn't add much
heat, it changes the way the heat is distributed. And this has
surprisingly large effects in some areas. It's possible to
estimate the total global energy use from all sources, then
compare that to the factors that are known to drive the climate
(called "forcings"). And it turns out to be rather minor; less
than 0.1 Watt/m2 when averaged out over the globe. In contrast,
the current forcing from human-delivered CO2 is about 1.5
Watts/m2. Given that, the direct heating of the atmosphere due
to power consumption