The Marine-Air-Sea-Flux System (MASFlux) for Air-Sea Interaction Studies

Qing Wang, Naval Postgraduate School, Department of Meteorology, Monterey, United States, Richard Lind, US Naval Postgraduate School, Meteorology, United States, Ryan Yamaguchi, Naval Postgraduate School, Department of Meteorology, Monterey, CA, United States, John A Kalogiros, National Observatory of Athens, Institute of Environmental Research & Sustainable Development, Athens, Greece, Carlos Zuniga, Servicio Hidrografico y Oceanografico de la Armada de Chile, Valparaiso, Chile and Andrew E. Sweeney, US Navy, Washington, United States
Abstract:
Concurrent measurements of near surface turbulence fluxes, surface waves, and gradients of temperature, humidity, and wind are needed for understanding air-sea-wave interaction and to improve its representation in coupled forecast models. In addition, these measurements in the lowest few meters in undisturbed air are needed to quantify atmospheric effects on propagation of electromagnetic waves near the ocean surface. The Meteorology Department of the Naval Postgraduate School (NPS) has developed a small, easily deployable flux sampling system, the Marine-Air-Sea-Flux System (MASFlux) based on a small 0.5 m spar buoy. This system is designed to be very portable and introduce minimum flow distortion to its immediate surroundings. This presentation will describe the design and instrumentation of the buoy flux measurement system and some results from recent field deployments.

The MASFlux buoy is equipped to sample four levels of mean temperature and humidity in the lowest 3 m, two levels of mean wind, and one level of fast 3-D sonic anemometer at 3.5 m for momentum and heat flux measurements. A combination of compass, GPS, and accelerometers on the MASFlux provides full location and motion sensing to allow removal of platform motion in the turbulence measurements and retrieval of 2-D spectral wave information through buoy motion. In addition, the MASFlux buoy has three levels of water temperature measurements within half meter from the surface. This system can be deployed by two to three people from a small vessel.

The MASFlux has been deployed at sea multiple times in Monterey Bay, off the coast of Virginia Beach, and offshore of Duck, NC. Some of the results will be discussed here to show the capability of the MASFlux in air-sea interaction related research. In addition to showing the capability of the buoy in sampling the air-sea interface, the wave boundary layer characteristics will also be discussed.