Emanuel replies: Michael Binkley advances an interesting idea to deprive tropical cyclones of their power source. In principle, it would work, if one could cool a strip of ocean roughly 100 km wide along the path of the cyclone. For average conditions in the tropics, a cooling of 2.5 °C would eliminate the necessary thermodynamic disequilibrium altogether, so even a 1 °C cooling would have a noticeable effect.
The technical difficulty here is one of time scale. The upper tropical ocean is typically well mixed by turbulence, through a depth of roughly 50 meters. To cool that layer by 2.5 °C, one would need to shut off sunlight for about 30 days, and roughly a week to achieve a 1 °C cooling. That is far longer than the time scales over which storm tracks can be predicted, and so one would be forced to cool a vast region of the tropical Atlantic Ocean. That would no doubt have unforeseen and probably undesirable consequences.
Given the high toll that hurricanes extract in human suffering, it is certainly worth contemplating means by which they might be tamed.
