FORMOST-3/COSMIC mission to global earth weather monitoring, operation, and TACC/CDAAC post-processing

Active limb sounding of the atmosphere using radio occultation of Global Positioning System (GPS) radio signals received in low-earth-orbit (LEO) had been flight demonstrated by the GPS/MET experiment aboard NASA's MicroLab-I spacecraft since 1995. The follow-on FORMOSAT-3/COSMIC mission is a collaborative Taiwan-U.S. program to deploy a constellation of six LEO satellites for space weather monitoring (ionosphere and atmosphere), global operational weather prediction, and climate change research. The program is jointly undertaken by the National Space Organization (NSPO) in Taiwan and the University Corporation for Atmospheric Research (UCAR) in the U.S., in collaboration with Central Weather Bureau (CWB) of Taiwan, Jet Propulsion Laboratory (JPL) and Naval Research Laboratory (NRL), and with the participation of many government, academic and private organizations. The planned launch date is set at the spring of 2006. The scientific goals for FORMOSAT-3/COSMIC are to (1) improve global and regional weather forecasting by collecting data for atmospheric and Ionospheric application; (b) improve global space weather monitoring and forecasting, especially in data sparse regions including the oceans and near the poles; (c) provide data sets for climate change and global warming detecting research, this system will provide valuable information for predicting magnetic storms and other important space weather effects; and (d) advance earth gravity field knowledge and engineering sciences. The six satellites constellation will promise global atmospheric monitoring at some 2,500 points spread uniformly around the globe, with high accuracy. The mission operation of this program is divided into three major phases: (1) Launch and early orbit (L&EO) checkout, (2) Orbit transfer and constellation deployment, and (3) Real-time operational demonstration. Each phase offers an opportunity to address specific challenges in metrology and climate, space weather, and geodesic science. With the demonstration of real-time operations, FORMOSAT-3/COSMIC data will complement other earth observing systems and improve global weather analyses, particularly over the oceans and polar regions, and Numerical Weather Prediction (NWP) forecasts. There are two data centers for receiving and processing the science data: (1) the COSMIC Data Analysis and Archive Center (CDAAC) located at Boulder, Colorado, USA, and (2) the Taiwan Analysis Center for COSMIC (TACC) at CWB. TACC is not noly served as a mirror site of CDAAC, but also a fully operational data center for COSMIC. TACC will perform its own analysis of the data and distribute its products and CDAAC products to the global users' community. The processed results shall be ready for assimilation into weather prediction model, on average, within 3 hours from the time of data collection in orbit. The success of FORMOSAT-3/COSMIC mission will inaugurate an age of operational GPS sounding for weather forecasting, climate prediction, ionospheric monitoring, and a suite of related earth science pursuits.