HR: 1340h
AN: A43A-0070 [Abstracts]
TI: GPS Radio Occultation with CHAMP and SAC-C: Global and Seasonal Variations of Gravity Wave
Activity
AU: * Kishore, P
EM: kishore@nict.go.jp
AF: National Institute of Information and Communications Technology, International Alliance Division
Tokyo
Japan
4-2-1 Nukui kita machi
Koganei-shi
, Koganei, 1848795
Japan
AU: Namboothiri, S
EM: nambooth@nict.go.jp
AF: National Institute of Information and Communications Technology, International Alliance Division
Tokyo
Japan
4-2-1 Nukui kita machi
Koganei-shi
, Koganei, 1848795
Japan
AU: Igarashi, K
EM: igarashi@nict.go.jp
AF: National Institute of Information and Communications Technology, International Alliance Division
Tokyo
Japan
4-2-1 Nukui kita machi
Koganei-shi
, Koganei, 1848795
Japan
AU: Jiang, J
EM: Jonathan.H.Jiang@jpl.nasa.gov
AF: Jet Propulsion Laboratory
, Microwave Atmospheric Science Team
Mail Stop 183-701
4800 Oak Grove Drive
Pasadena, California, Pasadena, 91109
United States
AB:
Gravity waves in the middle and upper atmosphere are believed to be excited mainly in the troposphere and lower stratosphere
(TLS) and propagate upward, resulting in energy coupling between the lower and upper atmosphere. Therefore, it is of
significant importance to study the basic features of gravity wave activities in the TLS. GPS satellites provide global
atmospheric profiling with high vertical resolution (0.1-1 km) and high accuracy under all weather conditions. Recent
satellites on board the German CHAMP (CHAllenging Minisatellite Payload) and the Argentine SAC-C (Satellite de Aplicaciones
Cientificas-C) have allowed us to analyze gravity waves in the troposphere as well as in the stratosphere on near-global
basis. The present study considers a data sample for 44 months that begins from May 2001 to December 2004 for CHAMP and 40
months from July 2001 to December 2004 for SAC-C occultation data sets. Seasonal and latitudinal variations of Potential
energy (Ep) are evident at 20-30 km; in particular, Ep values are highly enhanced near the equator. Amplitudes of temperature
fluctuations at 20-30 km could be somewhat reduced through the optimization of the occultation analysis. We have
investigated variations of (T'/T)2 at 10-20 km and 20-30 km as a function of latitude and season.
DE: 0342 Middle atmosphere: energy deposition (3334)
DE: 0350 Pressure, density, and temperature
DE: 0394 Instruments and techniques
SC: Atmospheric Sciences [A]
MN: Fall Meeting 2005