The FORMOSAT-3/COSMIC (F3/C) constellation launched on 15 April 2007, consisting of six micro-satellites in low-Earth orbit, is capable of monitoring the troposphere and ionosphere by using the powerful technique of radio occultation. With more than 2500 observations per day, it provides an excellent opportunity to monitor three-dimensional structures and dynamics of the tropospheric and ionospheric climatology. Vertical profiles of the temperature and pressure in the troposphere as well as those of the electron density in the ionosphere are derived from the GPS occultation experiment (GOX) onboard F3/C. Pronounced signatures of El Niño and La Niña associated with the Walker Circulation, reversed Hadley Circulation along the Tibetan Plateau-Indian Ocean longitude, and planetary wave signatures in the Polar Regions are presented. Meanwhile, prominent equatorial ionization anomaly (EIA) and interesting plasma depletion bay (PDB) over oceanic areas near the geomagnetic equator are observed by the F3C/GOX. The EIA are well-developed during the daytime when the equatorial plasma fountain becomes prominent, while the PDB simply appears in nighttime. Some mechanisms are proposed to explain the formation of the two ionospheric features. Finally, the F3C/GOX observes that the ionospheric electron density significantly decreased and/or increased 3-6 days before the May 12, 2008 Wenchuan Earthquake. The amorous decreases and increases suggest that vertical electric fields on Earth's surface might play an important role to the lithosphere-atmosphere-ionosphere coupling.

Jann-Yenq (Tiger) Liu joined the National Central University (NCU), Taiwan in 1990, and is currently visiting NCAR/HAO at Boulder, Colorado (July 2009 - July 2010). He has been teaching and researching in ionospheric radio physics, space physics, and GPS geosciences applications at Institute of Space Science at NCU. He currently is the president of the Taiwan COSPAR. Prof. Liu received his MS and PhD degrees in Physics at Utah State University.