Satellite Measurements of Sea Level Change: Where Have We Been and Where Are We Going
R. S. Nerem(1) , D. P. Chambers(2) , E. W. Leuliette(1) , and G. T. Mitchum(3)
University of Colorado,
Boulder, CO, 80309-0431,
(2) University of Texas at Austin, 3925 W. Braker Lane #200, Austin, Texas, 78712, United States
(3) University of South Florida, 140 Seventh Ave. South, St. Petersburg, FL 33701, United States
Over the last few decades, satellite geodetic measurements together with in situ measurements, have revolutionized our understanding of present-day sea level change. With measurements from satellite altimeter missions and satellite gravity missions, we are now able to start answering some important questions with regards to global sea level change and its regional variations. What have we learned from these measurements? Would we change any of the decisions we made in the past? What are the remaining questions to be answered? What suite of measurements are needed to answer these questions? The record of sea level change from satellite altimetry will be reviewed, its error sources and limitations discussed, and the results placed in context with other estimates of sea level change from tide gauges, in situ measurements, and global climate models. The much shorter, but just as important, record of ocean mass variations from satellite gravity measurements will be similarly reviewed. Finally, the need for continuing the satellite measurements of sea level change, and possibly developing new measurements, will be discussed in the context of future missions and the scientific gain that would result.