Figure 9-5: Convection in the Kitchen Heat supplied to the bottom of a pot warms the water there, making the water expand and lowering its average density. This low-density water rises and transfers heat to its cooler surroundings. The water that began at the bottom thus cools down, becomes denser, and sinks back to the bottom to repeat the process.

(Adapted from F. Press, R. Siever, T. Grotzinger, and T. H. Jordan, Understanding Earth, 4th ed., W. H. Freeman, 2004)