Coupling Processes in the Equatorial Atmosphere

点击翻译按钮获取中文摘要

The Indonesian Archipelago is one of the centers of intense atmospheric motions over the globe. The mechanisms of these atmospheric motions and their changes, however, have not yet been made clear due to the sparseness of observational data in that region. The Coupling Processes in the Equatorial Atmosphere (CPEA), a six-year research project of Japan, was conducted in Indonesia to observationally elucidate dynamical and electrodynamical coupling processes occurring in the equatorial atmosphere from September 2001 to March 2007. During six years of CPEA, a new Equatorial Atmosphere Observatory was established with the Equatorial Atmosphere Radar (EAR) as the core facility in Kototabang, West Sumatra, Indonesia (0.20??S, 100.32??E). In the present talk we will review some highlights from this project. First, it has been found, contrary to the traditional expectation, that deep convection over Sumatra Island is observed in inactive phase of Madden-Julian Oscillation (MJO), while shallow convection is dominant in active phase. Secondly, clear correlation between deep convection and enhanced inertia gravity waves with period 2-3days was found with their wave source identified as slowly eastward advecting convection. Thirdly, Kelvin waves with periods 10-12 days near the tropopause and 5.5-8 days in the lower stratosphere were detected locally overIndonesia and globally by CHAMP-GPS. Fourthly, several pieces of evidence have been provided to demonstrate that long-term variability in the troposphere influences the dynamics of the mesopause-homopause region. Finally, it has been suggested that gravity waves near 100 km in altitude contribute to generation of plasma bubbles.