资源环境科技发展态势分析平台

During the Deep Propagating Gravity Wave Experiment (DEEPWAVE) 13 July 2014 research flight over the South Island of New Zealand, a multiscale spectrum of mountain waves (MWs) was observed. High-resolution measurements of sodium densities were available from similar to 70 to 100km for the duration of this flight. A comprehensive technique is presented for obtaining temperature perturbations, T, from sodium mixing ratios over a range of altitudes, and these T were used to calculate the momentum flux (MF) spectra with respect to horizontal wavelengths, (H), for each flight segment. Spectral analysis revealed MWs with spectral power centered at (H) of similar to 80, 120, and 220km. The temperature amplitudes of these MWs varied between the four cross-mountain flight legs occurring between 6:10UT and 9:10UT. The average spectral T amplitudes near 80km in altitude ranged from 7-13K for the 220km (H) MW and 4-8K for the smaller (H) MWs. These amplitudes decayed significantly up to 90km, where a critical level for MWs was present. The average MF per unit mass near 80km in altitude ranged from similar to 13 to 60m(2)/s(2) across the varying spectra over the duration of the research flight and decayed to similar to 0 by 88km in altitude. These MFs are large compared to zonal means and highlight the importance of MWs in the momentum budget of the mesosphere and lower thermosphere at times when they reach these altitudes.