chapter  14
24 Pages


The general circulation (Chapter 12) is the sum of the synoptic-scale winds (Chapter 13), averaged over space and time, and these in turn contain local surface winds, which are the topic of this chapter. The flow of these local winds around surface irregularities generates swirls which eventually cause frictional heat, i.e. increased vibration of the air molecules. So there is a chain of descending scale and increasing irregularity of motion, as the Sun’s radiation (which fundamentally energises all the various circulations) degenerates to the least useful form of power: low-temperature heat.