Collaborative Research: Investigating the Relationship Between Ocean Surface Gravity-Capillary Waves, Surface-Layer Hydrodynamics, and Air-Sea Momentum Flux

Ocean surface waves mediate the transfer of momentum, heat, and gas across the air-sea interface. Yet there exist very few detailed observations of the role of short ocean wave growth and directionality in mediating these exchanges. This project is to analyze a large set of ocean surface wave, near-surface hydrodynamics, and air-sea momentum flux data collected at the Air-Sea Interaction Tower (ASIT) between late 2019 and early 2020. The proposed work will help to resolve fundamental aspects of the relationship between air-sea momentum flux, ocean surface waves, and near-surface hydrodynamics. The results will be incorporated into classroom material for a new course on physical air-sea interaction at the University of New Hampshire and an existing course at Columbia University. Additionally, the results will be made available to K-12 teachers in the New York City area through the LDEO program "Earth2Class (E2C) Workshops for Educators".

The project will quantify the relationship between wind forcing and the directional growth and relaxation of short surface gravity and gravity-capillary waves. The air-sea momentum fluxes will be addressed by combining the observed thermal skin advection and short-wave propagation data with the atmospheric turbulent stress profile and subsurface velocity profile. One of the outcomes of this project will be to produce a new parameterization for the ocean surface current response to wind forcing that incorporates turbulent stress and the ocean surface wave state.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.