Global structure, seasonal and interannual variability of the migrating semidiurnal tide seen in the SABER/TIMED temperatures (2002-2007)

摘要

In the present reply we focused on three topics:rn- By a detailed comparison between the seasonal characteristics of the SABER/TIMED semidiurnal oscillation, composed of all semidiurnal tides with zonal wavenum-ber up to 4, for a geographic point (40° N, 105° W) and the Na lidar observations over Fort Collins, Colorado (41° N, 105° W) it was provided clear evidence that there is no system-dependent vertical wavelength and that the September amplification in the altitude range of 80-90 km is affected by the nonmigrating tides. We pointed out also that when the altitude distribution of the vertical phase gradient is variable the calculation of the vertical wavelength using observations only from an altitude range shorter than the wavelength itself could be rather misleading. This is a significant weak point of the ground-based radar and lidar measurements.