THE SEEK CHEMICAL-RELEASE EXPERIMENT - OBSERVED NEUTRAL WIND-PROFILE IN A REGION OF SPORADIC-E

Wind measurements made with the chemical release technique during a sp oradic E layer event are presented. The data were obtained as part of the Sporadic E Experiment over Kyushu (SEEK) sounding rocket campaign. The winds show a strong maximum in the lower E region approaching 150 m s(-1) near 105-km altitude and a large shear below the maximum. The large shear was within a few kilometers altitude of the peak in the e lectron densities measured on the downleg of the rocket trajectory. Ca lculations of the Richardson numbers for the wind profile show that th e altitude range near the layer was highly unstable.