Impact of the latitudinal distribution of tropical cyclones on ocean heat transport

The heavy winds associated with tropical cyclones generate strong upper ocean mixing. Recent studies suggest that this enhanced mixing significantly contributes to the ocean poleward heat transport, mainly due to a strengthening of the subtropical cells. A general circulation model is used here to show that whether the poleward heat transport is actually increased depends crucially on the latitude band where mixing is enhanced. If upper ocean mixing is enhanced everywhere within 30° of the equator, poleward heat transport is increased. However, if mixing is enhanced solely in the subtropical bands, where tropical cyclones are observed, the poleward heat transport out of the deep tropics is decreased.