Response of the Hydroxyl Layer to Small Vertical Scale Gravity Waves Propagating in a Realistic Windy Atmosphere

U.B. Makhlouf1, R.H. Picard2, J.R. Winick2, T.F. Tuan3, E. Ryan4

1 Stewart Radiance Laboratory, Bedford, MA 01730
2 Phillips Laboratory, Geophysics Directorate, (PL/PG/OPS), Hanscom AFB, MA 01731
3 University of Cincinnati, Physics Department, Cincinnati, OH 45221
4 University of Miami, Meteorology and Physical Oceanography, Miami Fl 33149

Abstract:

Small vertical scale gravity waves with vertical wavelength less than 20km and small horizontal phase speed are frequently observed in atmospheric data. Previously, we formulated a coupled photochemical/dynamical model for the response of the OH Meinel airglow to a monochromatic gravity wave perturbation in a realistic non-isothermal atmosphere with background wind. We have modified this model for the case of small scale waves by numerically integrating the hydrodynamic equations with a ground boundary condition. The ground boundary condition replaces the boundary condition at 240km in the previous model and avoids having to integrate through high altitude critical layers, which would absorb the small scale waves. We calculate the Krassovsky ratio for various wave periods and compare the results to those obtained using an isothermal model. We also discuss the sensitivity of the results to the background temperature chosen for the isothermal model.

Reference:

Response of the Hydroxyl Layer to Small Vertical Scale Gravity Waves Propagating in a Realistic Windy Atmosphere. U.B. Makhlouf, R.H. Picard, J.W. Winick, T.F. Tuan, E.H. Ryan, 1993 Fall Meeting, Eos, Transactions, AGU, 74 (43), October 26, 1993, (SA31A-08).