Estimate L-band interferometric phase ramps from dense regional GPS network

Tuesday, 15 December 2015
Poster Hall (Moscone South)
Wenliang Zhao1, Yunjun Zhang1, Falk Amelug2 and Yosuke Aoki3, (1)University of Miami, Miami, FL, United States, (2)University of Miami, Miami, FL, United States, (3)University of Tokyo, Bunkyo-ku, Japan
Long wavelength phase ramps in InSAR data are considered as orbital error for a long time until Fattahi and Amelung (2014) proved its falseness. It explains pretty well for C and X band sensor, such as Envisat ASAR, Sentinel-1 and TerraSAR-X, but not for L-band ALOS PALSAR. We propose that this unexpected phase ramp in L-band InSAR data is caused by the seasonal change of ionospheric total electron content (TEC). We use dense regional GPS network (GEONET) in southwest Japan to map TEC and estimate the corresponding interferometric phase delay.