1. a Colorado Center for Astrodynamics Research , University of Colorado , Boulder , Colorado , USA
2. b Laboratory for Satellite Altimetry , National Oceanic and Atmospheric Administration (NOAA) , Silver Spring , Maryland , USA
3. c SGT Inc., NASA GSFC , Greenbelt , Maryland , USA
4. d Centre for Australian Weather and Climate Research and Wealth from Oceans Flagship, CSIRO Marine and Atmospheric Research , Hobart , Tasmania , Australia
5. e CLS , Ramonville Saint-Agne , France