Spatial and Temporal Variation of the FORMOSAT-‐3/COSMIC S4 scintillation index using Tidal Analysis
Pei‐yun Chiu1, Loren Chang2
1,2National Central University, Taiwan, Jhongli, Taiwan
The tides from the lower atmosphere can propagate upward, causing the ionospheric perturbations. Although lacking in height information, the total electron content (TEC) is still effective in presenting these disturbances. On the other hand, FORMOSAT-‐3/COSMIC satellites can provide global morphology of the scintillation index, S4 index, by using GPS radio occultation (RO) signals. We focus on the universal time and spatial variation of the S4 index, and quantify the major variation modes through tidal analysis. The seasonal variations of the S4 index are presented in this method from 2007 to 2014 and the tidal signatures are examined.