Page 218 - Materials Chemistry, Second Edition

204 R.K. Rosenbaum et al.

• Forest dieback (Boreal forest, Amazon rainforest).
• Area encompassed by monsoon systems will increase with intensified
precipitation.

10.6.2 Environmental Mechanism

In principle, the energy reaching the Earth’s atmosphere from solar radiation and
leaving it again (e.g. via reflection and infrared radiation) is in balance, creating a
stable temperature regime in our atmosphere. As shown in Fig. 10.7, from the
sunlight reaching the Earth’s atmosphere, one fraction (*28%) is directly reflected
back into space by air molecules, clouds and the surface of the earth (particularly
oceans and icy regions such as the Arctic and Antarctic): this effect is called albedo.
The remainder is absorbed in the atmosphere by greenhouse gases (GHG) (21%)
and the Earth’s surface (50%). The latter heats up the planetary surface and is
released back into the atmosphere as infrared radiation (black body radiation) with a
longer wave length than the absorbed radiation. This infrared radiation is partially
absorbed by GHGs and therefore kept in the atmosphere instead of being released
into space, explaining why the temperature of the atmosphere increases with its
content of GHGs.

Fig. 10.7 The greenhouse effect (©User: ZooFari/Wikimedia Commons/CC-BY-SA-3.0)