Figure 11.2

Figure 11.2. (a) The circulation around a low-pressure system sends warm air poleward to the east of the low and colder air equatorward on the western side. The convergence in the vicinity of the low tends to sharpen temperature contrasts; (b) Lows can derive energy from these sharpening temperature contrasts. As more and more isobars encircle the low, winds strengthen and the low can send warm air farther northward and cold air farther southward.