FORMOSAT-3/COSMIC Measurement of Neutral Atmosphere: Results, Data Quality Statistics, and Status

Vertical temperature and pressure profiles of neutral atmosphere have been observed by Microlab-1, CHAMP, and SAC-C by using GPS occultation technique. Recently, six FORMOSAT-3 satellites were lunched into space on April 14, 2006 US time. The six satellites forming a constellation receive signals transmitted by the GPS satellites. The bending of GPS signals transecting the Earth's atmosphere is retrieved to determine the atmosphere's variable profiles. It is estimated that in full operation the FORMOSAT-3 satellites will provide about 2500 vertical profiles of the atmosphere for weather prediction, meteorological research, and typhoon path prediction. This paper reports the FORMOSAT-3 configuration and current status, results of atmospheric profiles, quality statistics of data, and analysis of the relationship between precipitable water vapor and occultation signals, statistics of occultation events distribution and lowest altitude retrieved by the GPS occultation technique. The results show the success of the FORMOSAT-3 mission with great potential of the data for further applications in atmospheric research and weather forecasting.