The rapid rotation and resulting strong Coriolis effects (see Chapter 9) in the atmospheres of the giant planets create much stronger zonal winds than are present in the atmospheres of the terrestrial planets, even though less thermal energy is available. Figure 10.14 shows the zonal wind patterns on the giant planets. On Jupiter the strongest winds are equatorial westerlies, which have been clocked at speeds of 550 kilometers per hour (km/h—Figure 10.14a). (Recall from Chapter 9 that westerly winds are those that blow from, not toward, the west.) At higher latitudes the winds alternate between easterly and westerly in a pattern that might be related to Jupiter’s banded structure. Near a latitude of 20° south, the Great Red Spot appears to be caught between a pair of easterly and westerly currents with opposing speeds of more than 200 km/h. This fact reveals something about the relationship between zonal flow and vortices, as we’ll discuss in the next section.