Showing papers by "Michael P. Hickey published in 2003"
TL;DR: In this paper, the authors used a numerical model to study the dissipation in Jupiter's thermosphere of upward propagating acoustic waves and found that acoustic waves mainly heat the Jovian thermospheres through effects of molecular dissipation, sensible heat flux divergence, and Eulerian drift work.
56 citations
TL;DR: In this article, the interaction of transient, dissipating gravity wave packets with the minor species involved in the OH airglow chemistry in the mesopause region reveal large wave-driven downward fluxes of minor species.
Abstract: [1] Numerical simulations of the interaction of transient, dissipating gravity wave packets with the minor species involved in the OH airglow chemistry in the mesopause region reveal large wave-driven downward fluxes of the minor species. In addition to the minor species fluctuating in response to the wave, a strong secular variation of minor species densities occurs. At 90 km altitude this secular variation becomes significant ∼80 min after the wave packet onset, and increases approximately linearly with increasing time for the following 2 hours. At later times the secular variation diminishes. Heating rates due to exothermic chemical reactions consequently exhibit a fluctuating component as well as a secular variation. When averaged over time, the net effect of each of the two waves considered is to cause large (∼22% and 37%) increases in average heating rates. This secular variation in heating rates could be more significant than the present results suggest because larger amplitude gravity waves can exist in the mesopause region.
17 citations
TL;DR: In this article, the authors investigate the temporal and spatial variations of the local and integrated response of minor species and OH emission to a small-scale gravity wave and find that the second-order terms will also be important for narrow minor species profiles having large gradients (or small scale heights).
Abstract: [1] We investigate the temporal and spatial variations of the local and integrated response of minor species and OH emission to a small-scale gravity wave. A Chapman-like function is used to model the unperturbed profiles of minor species like ozone, hydrogen, and OH emission. Because the gravity waves that we simulate do not violate the nonacceleration conditions, the waves will not cause a secular variation in the minor species concentrations. We therefore use the Krylov-Bogoliubov-Mitropolsky averaging method to remove the higher-order secular terms in our perturbation expansion. A vertical drift velocity, second order in nature, is required to remove the secular terms. The equivalence of this vertical drift velocity to the Eulerian drift is demonstrated. Using the perturbation method to treat the response of minor species to a small-scale gravity wave, we compute the first- and second-order perturbation terms and find that the second-order terms will also be important for narrow minor species profiles having large gradients (or small-scale heights).
8 citations