[1] NOAA, Pacific Marine Environm Lab, 7600 Sand Point Way NE, Seattle, WA 98115 USA
[2] Helmholtz Ctr Polar & Marine Res, Alfred Wegener Inst, Telegrafenberg A43, D-14473 Potsdam, Germany
[3] Rutgers State Univ, Dept Marine & Coastal Sci, 71 Dudley Rd, New Brunswick, NJ 08901 USA
[4] Univ Sheffield, Dept Geog, Winter St, Sheffield S10 2TN, S Yorkshire, England
[5] Korea Polar Res Inst, Inchon, South Korea
[6] Univ Exeter, Coll Engn Math & Phys Sci, Exeter EX4 4QE, Devon, England
[7] Univ Reading, Dept Meteorol, POB 243, Reading EG6 6BB, Berks, England
[8] Finnish Meteorol Inst, Erik Palmenin Aukiol 1, FI-00560 Helsinki, Finland