Book Description
Strong wind and vertical wind shear must be considered for design and operation of vehicles that will either operate in or penetrate the upper stratosphere and mesosphere. Global extremes of these atmosphere parameters are estimated in this report for altitudes above 30 km. For the Northern Hemisphere estimated 90, 95, and 99% winds, related to the windiest months and locations, are provided for altitudes between 30 and 80 km. Speed increases up to about 55 km and appears to decrease thereafter up to at least 75 or 80 km in November, December, and January. The 99% winds can be expected to approach 215 mps near 55 km at certain locations between latitudes 35 and 60N. For the Southern Hemisphere 90, 95, and 99% winds are provided for altitudes between 30 and 60 km. The 99% winds reach roughly 200 mps near 55 km. Since estimates for the Southern Hemisphere are not necessarily representative of either the windiest month or location, results are uncertain and speeds probably will be somewhat larger than indicated. For the same percentiles, 1-km thick vertical wind shears have been estimated for altitudes between 30 and 70 km. Shears generally increase, and maximum values tend to move equatorward with altitude. (Author).