Kerry Emanuel’s elegant description of hurricanes as heat engines (Physics Today, August 2006, page 74) leads to the question of whether it might be possible to weaken a hurricane by interfering with that engine. It is well known that covering the water with a surfactant can reduce water evaporation by an order of magnitude. If that could be done in advance of a hurricane, the amount of latent heat of condensation available to drive the storm would be reduced.

Dispensers of surfactant could be placed on the ocean floor in the path of a hurricane. They could be distributed by aircraft along the storm’s path a few days before its predicted arrival, or earlier and more broadly on the continental shelf, and opened by acoustic signal when a storm is imminent. The quantity of surfactant required is modest: Covering a 100 km x 1000 km storm track with a monolayer requires only about 100 tons.

The important questions are how long the surfactant layer would last (it could be continuously replenished by suitable dispensers), how effective it would be in reducing evaporation in real near-hurricane ocean conditions, and how much effect it would have on the hurricane. These questions can only be answered empirically, but the cost of such an experiment would be much less than the damage—tens of billions of dollars—that a severe hurricane would do to a populated seacoast.