One example of a subsidence inversion is the Trade wind inversion, common over much of the subtropical oceans (Figure 7.10). It lies about 500 m above sea-level in regions where the surface is relatively cool, e.g. off northern Chile and Peru, and also off the south-west coast of Africa (Chapter 11). The top of the inversion there is about 8 K warmer than the base. Nearer the equator, there is more convection from the warmer surface so that the inversion there occurs at 1,500 to 2,000 m. The inversion there is weaker and thinner because warmer seas imply less subsidence. Overall, the pattern of inversion strength is reflected in the patterns of fog (Chapter 8) and rainfall (Chapter 10).
Even where subsidence is insufficient to create an inversion, it still enhances atmospheric stability. Thus, easterly winds in coastal Peru and northern Chile are stabilised by the descent from the Andes, making uplift less likely and so reducing rainfall (Chapter 10).
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