DMS transfer velocities above 10 m/s

We measured the sea/air flux of DMS by eddy correlation (EC) in two programs that encountered higher winds and seas than our previous cruises. As a part of the Deep Ocean Gas Exchange Experiment, DOGEE, we measured fluxes and sea water concentrations of DMS in the North Atlantic from the UK ship RRS Discovery in June and July of 2007. During the Southern Ocean Gas Exchange Experiment (SO-GasEx), we made similar measurements east of the southern tip of South America aboard the NOAA ship R/V Ronald H. Brown in Feb and March of 2008. Wind speeds during DOGEE ranged from nearly calm to over 15 m/s, while a few samples during SO-GasEx were near 20 m/s. DMS exchange velocities during DOGEE were nearly linear vs wind speed, close to Wanninkhof (92) below 5 m/s and Liss and Merlivat (87) from 9-13 m/s. All the exchange velocities during SO-GasEx were considerably smaller, roughly half the DOGEE values in the 9-13 m/s range. Above 15 m/s Kdms clearly decreased with wind speed. Possible explanations include surface DMS depletion, asymmetric exchange from bubble dissolution, and the reduction of tangential stress in favor of momentum transfer to waves (Soloviev and Schlüssel, 96).