
6 Engineering Response to Climate Change
1.3.3 Greenhouse Effect and Evidence of Global Warming
1.3.3.1 Global Energy Balance
The earth is heated by radiation from the sun. In turn, an equal amount of radi-
ation must leave the top of the atmosphere for the earth to maintain a balance
so that it does not either heat up or cool down. The interaction of radiation with
the atmosphere and the earth’s surface is very complicated. However, we can
get a general picture of it by summarizing the earth– atmosphere energy bal-
ance on average for the whole globe, that is, for a global average (Forster etal.
2007); see Figure 1.1. Suppose that 342 W/m
2
of ...