9:00 AM - 9:15 AM
[ACG10-13] Global Distribution of Vertical Wavenumber Spectra in The Lower Stratosphere Observed Using High-Vertical-Resolution Temperature Profiles from COSMIC GPS Radio Occultation
Latitude and time variations in the spectral parameters were investigated in two longitudinal regions: (a) 90–150º E, where the topography was more complicated, and (b) 170–230º E, which is dominated by oceans. We compared EpT , EpS , and p, with the mean zonal winds (U) and outgoing longwave radiation (OLR). We also show a ratio of EpS to EpT and discuss the generation source of EpS . EpT and p clearly showed an annual cycle, with their maximum values in winter at 30–50º N in region (a), and 50–70o N in region (b), which was related to the topography. At 30–50º N in region (b), EpT and p exhibited some irregular variations in addition to an annual cycle. In the Southern Hemisphere, we also found an annual oscillation in EpT and p, but it showed a time lag of about 2 months relative to U. Characteristics of EpT and p in the tropical region seem to be related to convective activity. The ratio of EpT to the theoretical model value, assuming saturated GWs, became larger in the equatorial region and over mountainous regions.