ISI Document Delivery No.: 502XE Times Cited: 3 Cited Reference Count: 27 Cited References: Alsdorf D, 2001, GEOPHYS RES LETT, V28, P2671, DOI 10.1029/2001GL012962 BAMBER JL, 1994, INT J REMOTE SENS, V15, P925 Birkett CM, 2002, J GEOPHYS RES-ATMOS, V107, DOI 10.1029/2001JD000609 BLACKWELL J, 2000, PAGE NT USERS MANUAL Brakenridge GR, 2005, EOS T AM GEOPHYS UN, V88, P185, DOI [10.1029/2005EO190001, DOI 10.1029/2005E0190001] CHELTON DB, 2001, SATELLITE ALTIMETRY, P1, DOI DOI 10.1016/S0074-6142(01)80146-7 CHENG K, 2004, 469 OH STAT U Cheng KC, 2008, TERR ATMOS OCEAN SCI, V19, P53, DOI 10.3319/TAO.2008.19.1-2.53(SA) CHRISTENSEN EJ, 1994, J GEOPHYS RES-OCEANS, V99, P24465, DOI 10.1029/94JC01641 CROARKIN C, 2005, NIST SEMATECH E HDB *EUR SAPC AG, 2009, ESA LAUNCH EARTH EXP FRAPPART F, 2005, REMOTE SENSING UNPUB Gesch D, 2001, MAR TECHNOL SOC J, V35, P58 GOAD CC, 1998, GPS GEODESY Herring T A, 2006, GAMIT REFERENCE MANU HOFMANNWELLENHO.B, 2004, GPS THEORY PRACTICE LEE H, 2009, MARINE GEODESY UNPUB Mader G., 1986, MANUSCRIPTA GEODAETI, V11, P272 Mader G. L., 1999, GPS SOLUT, V3, P50, DOI DOI 10.1007/PL00012780 MEADE RH, 1991, ENVIRON GEOL WATER S, V18, P105, DOI 10.1007/BF01704664 Niell AE, 1996, J GEOPHYS RES-SOL EA, V101, P3227, DOI 10.1029/95JB03048 Pavlis N.K., 2008, 2008 GEN ASS EUR GEO Saastamoinen I.I., 1973, B GEOD, V107, P13, DOI DOI 10.1007/BF02522083 SEYLER F, 2003, RAPPORT MISSION BRAN Shum C, 2003, MAR GEOD, V26, P335, DOI 10.1080/01490410390253487 Smith LC, 1997, HYDROL PROCESS, V11, P1427, DOI 10.1002/(SICI)1099-1085(199708)11:103.0.CO;2-S Watson C, 2003, MAR GEOD, V26, P285, DOI 10.1080/01490410390256745 Cheng, Kai-Chien Calmant, Stephane Kuo, Chung-Yen Tseng, Hong-Zeng Shum, C. K. Seyler, Frederique Da Silva, Joecila Santos SEYLER, Frederique/D-5518-2011; SILVA, Joecila/B-1478-2014 National Science Council of Taiwan [NSC 96-2116-M-194-006, NSC 97-2116-M-194-007]; National Geospatial-Intelligence Agency's University Initiative (NURI); Ohio State University Climate, Water and Carbon Program; France and Brazilian governments We are grateful to two anonymous reviewers' comments to this article. We acknowledge Gerald Mader of the U.S. National Geodetic Survey for his kind permission to use his Kinematic and Rapid Static (KARS) software for the computation of GPS water level measurements used in this study. The Taiwanese component of this study is partially supported by the grants of National Science Council of Taiwan (NSC 96-2116-M-194-006 and NSC 97-2116-M-194-007). The U.S. component of this study is supported by the National Geospatial-Intelligence Agency's University Initiative (NURI) program and by the Ohio State University Climate, Water and Carbon Program. The French and Brazilian components of this study are supported by grants from France and Brazilian governments. 3 TAYLOR & FRANCIS INC PHILADELPHIA MAR GEOD ; This study presents the result of a demonstration of Global Positioning System (GPS) hydrologic studies in a remote area. A GPS campaign was conducted using a GPS-equipped vessel and a GPS buoy to measure water level along Rio Branco, a tributary of the Amazon. The GPS water level data agree well with river gauge data and with ENVISAT radar altimeter measurements. The GPS-estimated river stage gradient of Rio Branco is 5.75 +/- 0.48 cm/km with 99% confidence, which is higher than previous estimates. This result also agrees well with ENVISAT altimetry results.