Large-scale planetary disturbances in stratospheric temperature at high-latitudes in the southern summer hemisphere

• Main Authors: M. G. Shepherd, T. Tsuda
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2008
• Subjects: Physics; QC1-999; Chemistry; QD1-999; Antarctic; Antarc*
• Online Access: https://doaj.org/article/bca20343973a414ebf9c4136bf70a01a

The global structure and propagation of large-scale (periods >5 days) waves in the Southern Hemisphere summer (December 2006–February 2007) at 60° S–75° S latitude are examined using temperature data from GPS radio occultation measurements by COSMIC/FORMOSAT 3 satellite constellation at 20 km and 30 km altitude. Spectral analysis has revealed eastward propagating planetary scale perturbations with wavenumbers 1 and 2 and periods of 10, 16 and 23 days, and stationary waves with wavenumbers 1 and 2. The results obtained show a very dynamically active Antarctic summer stratosphere. The novel aspect of the work is in the use of the GPS COSMIC data providing multiple local times each day, thus allowing large-scale wave analysis at high Southern latitudes and revealing planetary wave activity not normally observed in summer, but more consistent with late winter and spring conditions in the stratosphere.