We investigated the dissolution of CO:! drops in a high pressure counterflow water tunnel simulating ocean conditions down to 2000 m below the ocean surface. In comparison of the behavior of the buoyant CO2 drops observed in our experiments with that reported previously for motionless CO2 drops in seawater or water, the following significant differences are noticed: (1) the CO2 drops in buoyant motion dissolve much faster than the motionless CO2 drops and (2) hydrate does not always form on the buoyant CO2 drops, as it was reported in the literature to be an unavoidable phenomenon on the motionless drops. This suggests that buoyant motion influences the physical and chemical behavior of the CO2 drops in seawater dramatically. (C) 2000 Elsevier Science Ltd. All rights reserved.