stéphane CALMANT (IRD, France); Daniel MOREIRA (CPRM, Brazil); Marie-Claude GENNERO (CNES, France); Marie-paule BONNET (IRD, Brazil); Frédérique Seyler (IRD, FRENCH GUYANA); Frédéric FRAPPART (LEGOS, France); Taina CONCHY (UEA, Brazil); Robson OLIVEIRA (UEA, Brazil); Lucien BACHARACH (LEGOS, France)

SARAL is the very first mission collecting water levels over rivers in the Ka band. In the present study, we compare the capability of its altimeter AltiKa to that of previous missions working in the Ku band such as ENVISAT and Jason-2 in retrieving water levels over the Amazon basin. Same as for the aforementionned preceeding missions, the best results were obtained with the ICE-1 retracking algorithm. We qualitatively analyse the impact of rainfalls in the loss of measurements. Since making long -multi mission- time series is of major importance either for hydro-climatic studies or for basin management, we also present an estimate of the altimeter bias in order that the SARAL series of water level can be appended to those of these previous missions.