A PRELIMINARY-REPORT ON OBSERVATIONS OF EQUATORIAL ATMOSPHERE DYNAMICS IN INDONESIA WITH RADARS AND RADIOSONDES

Through collaboration between Japan and Indonesia, a radar observatory was established near Jakarta, Indonesia in November 1992, where we installed a meteor wind radar (MWR) and a boundary layer radar (BLR). Horizontal wind velocity and temperature fluctuations at 75-100 km were determined with the MWR with time and height resolution of 1 hour and 4 km, respectively. The BLR provided three components of wind velocity every minute in the planetary boundary layer (0.3-5 km) with a height resolution of 100 m. In addition, by combining an acoustic transmitter, temperature profiles were also obtained with the BLR by means of the PASS (radio acoustic sounding system) technique. Observations with the radars have been continued over 2 years since November 1992. Profiles of horizontal wind velocity, temperature and humidity were measured with radiosondes up to 35 km, with a height resolution of 150 m, four times a day during November 1992-April 1993 at LAPAN in Bandung. Further, radiosonde sounding has been routinely continued once a day after October 1993. Preliminary data analysis showed some new aspects of the equatorial atmosphere dynamics over Indonesia, such as the structure of the tropical planetary boundary layer and the behavior of atmospheric waves in the middle atmosphere. We report in this paper a description of the radar equipment, the current status of observations and the fundamental characteristics of equatorial atmosphere dynamics during the TOGA/COARE campaign.