Glossary of Fishery Terms - U

U

• Underwater acoustics - due to its excellent propagation properties, underwater sound is used as a tool to aid the study of marine life, from microplankton to the blue whale. See also Ocean Tracking Network.

• Upwelling - the process by which water, usually cold and nutrient-rich, rises from a deeper to a shallower depth. This is often a result of offshore surface water flow, particularly when persistent wind blows parallel to a coastland and the resultant Ekman transport moves surface water away from the coast.