A model is developed to calculate the upper ocean internal wave spectrum as modified by the surface boundary and mixed layer. The Garrett-Munk spectrum is assumed to describe the deep ocean wave field. The main effect of the surface and mixed layer is to align the vertical structure of the waves forming vertically standing waves locally; this contrasts with the assumption of random alignment in the Garrett-Munk model. Model spectra and coherences are calculated for idealized buoyancy frequency profiles and compared with the Garrett-Munk model. Measurements in the upper 200 m from the Mixed Layer Dynamics Experiment in the northeast Pacific in 1983 are also compared with the model results. The most striking success of the model is predicting the observed high coherence and 180¿ phase difference across the mixed layer of horizontal velocity. ¿American Geophysical Union 1987 |