Abstract:Using the high vertical resolution radiosonde data of May 2008 at the Hongyuan meteorological station located in the Tibetan Plateau, the observational characteristics of gravity waves in the lower stratosphere (19 to 26 km) are investigated. The results show that the dominant vertical wavelengths of the gravity waves are 2 to 4 km, with a mean value of 2.9 km; the dominant horizontal wavelengths are 100 to 600 km, with an average value of 311 km; the intrinsic frequency is dominated by 1.5f to 3.5f (Coriolis parameter), with a medium value of 2.5f, corresponding to an intrinsic period of 9 hours. The dominant (85%) wave energy propagation direction is upward; the horizontal propagation direction is mainly eastward. The dominant vertical intrinsic phase velocities range from -0.2 to 0.05 m/s, with an average value of -0.12 m/s; the dominant horizontal intrinsic phase velocities range from 5 to 15 m/s, with a mean value of 11.3 m/s.