Experiences on altimeter calibration at Ibiza island and Cape of Begur (Spain)
Tipus de documentText en actes de congrés
EditorEuropean Space Agency (ESA)
Condicions d'accésAccés obert
Three preliminary camp aigns for TOPEX /POSEIDON (T/P) wer e made in March 1999 and July 2000 and for JASON-1 in August 2002, in the NW Mediterran ean Sea at th e Begur Cape area. Dir ect abso lute altimeter calibration , and mapping of the sea surface, w ere made in these camp aigns from dir ect overflights using GPS buoys with a toroidal design performed at the I CC based in the orig inal design of the Univ ersity of Colorado at Boulder and a estimation of the TOPEX A lt- B bias w as made. A Spanish JASON-1 geoid gradien t campaign with Fench support has been made in June 2003 at the Ibiza island in the NW Mediterr anean Sea. Th e main objectiv e has b een to map w ith a new d esign ed, builded and calibrated GPS catamar an, the lo cal geoid gradien t in three ar eas around Ibiza island under the ascending (187) and descending (248) Jason-1ground tracks. The catamaran equ ipped with two GPS antennas to perform continuous sea lev el measur ements was towed by the Patro l Dev a from th e Span ish N avy. Five GPS reference stations were dep loyed on Ibiza island: one in Portinatx, two in San Anton io and two in Ibiza. The marin e geo id has been used to relate the coastal tide gauge data from Ibiza and San An tonio h arbours to off- shore altimetric data. In th e framework of the campaign, the levelling of the Ibiza and San Anton io tide gauges to the r espective GPS mark ers w as p erformed. We present synth esis of the resu lts obtained from Topex/Poseidon and th e first r esults on Jason-1 altimeter calibration using the direct measurements from GPS buoys and the derived marin e geoid. Th e Ibiza results agree relativ ely w ell with resu lts ob tained at Corsica, Harvest and Bass Strait calibration permanen t sites. Moreov er, the geod etic activities (e.g., GPS, levelling) has p ermitted to build a very accurate (few mm) local n etwork link ed to th e European one, w ith a reference frame compatible with th e satellite altimetry missions (ITRF2000). The GPS kinematic data wer e processed using two d ifferen t sof twar es allowing to check th e consistency of the solutions. A perspective of a new Jason-1, in cluding Envisat, Ibiza campaign to be made around 2007 will be pr esen ted. These camp aigns w ere supporte by th e Span ish Ministery of Scien ce and Technology under projects of the N ational Space Program ref : ESP1997-1816-CO4- 03 and ESP2001-4534-PE.
CitacióMartinez, J.J. [et al.]. Experiences on altimeter calibration at Ibiza island and Cape of Begur (Spain). A: Symposium on 15 Years of Progress in Radar Altimetry. "Proceedings of the Symposium on 15 Years of Progress in Radar Altimetry : 13-18 May 2006, Venice, Italy". Venècia: European Space Agency (ESA), 2006, p. 1-5.