COSMIC Observations of the Tropical Tropopause Layer

The Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) is a collaborative satellite project operated by the National Space Organization in Taiwan and the University Corporation for Atmospheric Research in the United States. The mission consists of six microsatellites launched in April 2006 that utilize the global positioning system radio-occultation limb sounding technique to provide high-precision temperature observations in the Upper Troposphere and Lower Stratosphere (UTLS). There are between 1000-2500 global occultation profiles taken daily with a vertical precision of approximately 200 metres in the UTLS. The global sampling coverage and precision of this data set is unprecedented and provides unique opportunities for the study of wave activity in the Tropical Tropopause Layer (TTL). COSMIC observations of the evolution of tropical waves will be shown with specific emphasis placed on latitudinal/longitudinal dependence and seasonality.