Japan Geoscience Union Meeting 2016

Presentation information

International Session (Oral)

Symbol A (Atmospheric and Hydrospheric Sciences) » A-CG Complex & General

[A-CG10] Earth and Planetary satellite observation projects Part II: Satellite Earth Environment Observation

Tue. May 24, 2016 9:00 AM - 10:30 AM 303 (3F)

Convener:*Riko Oki(Japan Aerospace Exploration Agency), Tadahiro Hayasaka(Graduate School of Science, Tohoku University), Kaoru Sato(Department of Earth and Planetary Science, Graduate School of Science, The University of Tokyo), Masaki Satoh(Atmosphere and Ocean Research Institute, The University of Tokyo), Yoshiaki HONDA(Center for Environmental Remote Sensing, Chiba University), Kenlo Nasahara(Faculty of Life and Environmental Sciences, University of Tsukuba), Takashi Nakajima(Tokai University, School of Information Science & Technology, Dept. of Human & Information Science), Taikan Oki(Institute of Industrial Science, The University of Tokyo), Tsuneo Matsunaga(Center for Environmental Measurement and Analysis, National Institute for Environmental Studies), Yukari Takayabu(Atmosphere and Ocean Research Institute, the University of Tokyo), Hiroshi Murakami(Earth Observation Research Center, Japan Aerospace Exploration Agency), Hajime Okamoto(Kyusyu University), Gail Skofronick Jackson(NASA Goddard Space Flight Center), Paul Chang(NOAA College Park), David Crisp(Jet Propulsion Laboratory, California Institute of Technology), Chair:Yoshiaki Honda(Center for Environmental Remote Sensing, Chiba University), Hiroshi Murakami(Earth Observation Research Center, Japan Aerospace Exploration Agency)

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

*Noersomadi Noersomadi1, Toshitaka Tsuda2 (1.Graduate Student of Graduate School of Science, Kyoto University, 2.Research Institute for Sustainable Humanosphere (RISH), Kyoto University)

We retrieved temperature (T) profiles with a high vertical resolution using the full spectrum inversion (FSI) method from the Constellation Observing System for Meteorology, Ionosphere and Climate (COSMIC) GPS radio occultation (GPS-RO) data from January 2007 to December 2009. We studied the characteristics of temperature perturbations in the stratosphere at 20–27 km altitude. This height range does not include a sharp jump in the background Brunt–Vaisala frequency squared (N2) near the tropopause, and it was reasonably stable regardless of season and latitude. We analyzed the vertical wavenumber spectra of gravity waves (GWs) with vertical wavelengths ranging from 0.5 to 3.5 km, and we integrated the (total) potential energy EpT. Another integration of the spectra from 0.5 to 1.75 km was defined as EpS for short vertical wavelength GWs, which was not studied with the conventional geometrical optics (GO) retrievals. We also estimated the logarithmic spectral slope (p) for the saturated portion of spectra with a linear regression fitting from 0.5 to 1.75 km.
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.