ABSTRACT
In this chapter, we will examine the chemistry of our atmosphere, although not in detail, as this is a massive subject in its own right. We need to understand that gas molecules in the Earth’s atmosphere are not ‘permanent’; rather, the gases they represent are in a constant state of flux, with molecules entering and leaving at rates which are in balance on timescales very much longer than a typical molecular residence time. For example, carbon dioxide is constantly being exchanged with the biosphere, which simply would not exist without it. Other exchanges are more subtle, but no less important. In addition, many important chemical reactions are taking place in our atmosphere, which also contribute to this dynamic balance.
