peak intensity over the western Caribbean. Hurricane Andrew of 1992 was a Category Five hurricane at peak intensity and was one of the strongest tropical cyclones ever to hit Florida.

HURRICANE-GENERATED WINDS AND WAVES

In the open ocean, the size of waves generated by a hurricane also depends on the force of the wind, the time that the wind has been blowing, and the condition of the sea (calm or stormy) prior to the arrival of the hurricane. However, hurricane-generated waves are different in one respect from ordinary wind waves—namely, the force producing the waves is moving in the same direction as the waves. For this reason the strength of hurricane-generated waves, especially in the long-period components, increases rapidly. Wind-generated waves do not always propagate in the direction of the wind.11

Waves produced by a hurricane depend on several factors, including the sustained wind speed, the pressure in the eye, the forward velocity of the center of the hurricane, and the radius of maximum wind speed—that is, how large the hurricane is. It also depends on the sea state before the hurricane—whether it was flat and calm, or whether a previous storm had already created waves that the hurricane could augment. Wave heights are not uniform across a hurricane; those on the right-hand side (when the storm is moving away from the observer) will be larger than those on the left-hand side, because they receive an added boost from the forward motion of the storm. Waves will begin to build when the eye of the storm approaches to within 90 to 100 miles.

Once formed, hurricanes generally turn to the north in the northern hemisphere and to the south in the southern hemisphere. This is called recurving. The track of tropical cyclones is due to the influence of the deep-layer mean flow in the lower and upper atmosphere. In the North Atlantic, the storms move in response to the large-scale flow around the Azores-Bermuda High in the lower atmosphere and also respond to traveling upper-level disturbances. They initially move westward on the southern side of the high, tending away from the equator. On the western side of the high, a hurricane starts following a



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