Laboratory for Middle Atmosphere and Global Environment Observation (LAGEO), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, China

摘要

We used a Rayleigh lidar located at Davis station, East Antarctica, to compare Polar Mesospheric Cloud (PMC) and stratospheric gravity wave (GW) strengths in the austral summer 2005–2006. Earlier similar studies from Greenland noted that intervals of large stratospheric GW activity appeared to coincide with reduced PMC strengths. We measure the stratospheric GW strength in the 30–45 km altitude range, for waves of vertical wavelength between ～2 and ～10 km, and of periods greater than 1 h. We find little consistency with the Greenland studies, as the occurrence of PMC over Davis appear to have little relationship to observed stratospheric gravity wave activity. Hemispheric differences, in both PMC strength and occurrence and in gravity wave strength, may have a role in explaining our results. Our data suggest that a significant controller of occurrence of PMC over Davis is related to diurnal tidal movement. We also investigate the potential influence of sampling biases in our data set.