Environmental Engineering Reference
In-Depth Information
11.4 Power densities of anthropogenic and natural
heat releases.
equal to 0.04% of the global mean insolation absorbed by
the continents (180 W/m
2
), a negligible increment
whose doubling or tripling would make no discernible
global difference. In contrast, by the year 2000 the cu-
mulative effect of global emissions of greenhouse gases
had already burdened the atmosphere with an additional
2.4 W/m
2
. Speculations about future anthropogenic
heat rejection depend on the dominant modes of primary
energy supply. Inexpensive photovaltaic electricity would
be (thermally speaking) a mostly invariable arrangement
redistributing a small share of insolation; in contrast, an
affluent civilization energized mostly by nuclear fission
could become a much more prodigious producer of
waste heat.
The average anthropogenic heat rejection rates for
such affluent, densely populated countries as Japan (1.8
W/m
2
) or the Netherlands (2.1 W/m
2
) are 2 OM
above the global mean, and the waste heat fluxes keep
