This numerical study of dynamical effects on the global distribution of atomic oxygen in the thermosphere makes use of a three-component model of upper atmospheric dynamics which treats the gases N2, O2, and O coupled together by collisions. This model simultaneously treats diurnal and seasonal variations of the distributions of these gases. Specific comparisons of hydrostatic computations with those taking into account wind-induced departures from hydrostatic equilibrium show that none of these gases can be considered to be in hydrostatic equilibrium below ~200 km. Global scale winds are shown to cause the observed winter enhancement of atomic oxygen in the lower thermosphere. Comparison of the model results with observational data shows generally good agreement.