Abstract: Multi-satellite altimetry has provided a wealth of data for measuring the long-term sea level change,T/P,Jason-1 and Jason-2 construct a seamless record of global sea level change from 1993 to present.We present the results of our calibration activities,including data comparisons during the tandem period of the missions,during which we resolve the relative bias between the missions,as well as comparisons to independent tide gauge data.When the entire record is assembled,global mean sea level change from 1993-2011 is 3.12±0.4 mm·a-1,and interannual variation is strongly correlated to El Nio phenomenon.