Modeling a rain-induced mixed layer

• Main Author: Hur, Hong Beom
• Other Authors: Nystuen, Jeffrey A.
• Published: Monterey, California: Naval Postgraduate School 2013
• Online Access: http://hdl.handle.net/10945/27761

Approved for public release; distribution is unlimited. === With the development of ocean surface remote sensing, air sea interaction theory and the theory of underwater sound generation at the ocean surface, the potential calming effect on surface gravity waves by raindrop induced mixing has become important. The rain induced mixed layer was studied with models based on the turbulent kinetic energy budget. A bulk mixed layer model was tuned with laboratory experimental data. The turbulent kinetic energy going into subsurface mixing was found to be less than 10% of the total raindrop kinetic energy. The length scale for mixing is proportional to both raindrop size and rain intensity. Furthermore, there is some indication of an initial penetration depth for raindrops. Although the available data was inadequate to complete model development and verification, a prediction for a hypothetical situation in the North Pacific is proposed. The diffusion processes are illustrated by solving for the diffusion and dissipation terms of the turbulent kinetic energy equation with a finite difference scheme. New experiments are suggested to allow future model development and testing.