1. Department of Earth and Planetary Sciences; The Johns Hopkins University; Baltimore Maryland USA
2. Now at Department of Marine and Environmental Biology; University of Southern California; Los Angeles California USA
3. Ocean Ecology Laboratory; NASA Goddard Space Flight Center; Greenbelt Maryland USA
4. Climate and Radiation Laboratory; NASA Goddard Space Flight Center; Greenbelt Maryland USA
5. Universities Space Research Association; Columbia Maryland USA
6. Sir Alister Hardy Foundation for Ocean Science; Plymouth UK