Simulating atmospheric tides in WACCM

Atmospheric tides are the dominant large-scale waves in the upper mesosphere and lower thermosphere. The Whole Atmosphere Community Climate Model (WACCM) simulates a full spectrum of migrating and nonmigrating tides that are spontaneously generated by the model physical and dynamical processes. However, the amplitudes of most WACCM tides in the mesosphere are substantially smaller than those observed. We will report on results of an investigation to determine the cause of the discrepancy. Processes investigated are the forcing, propagation, and damping of the tides and the impact of model vertical resolution, numerical parameterizations, and upper boundary conditions.