Analysis of Observations of Coherent Structures in the OBL
Abstract
LONG-TERM GOAL. The long-range goal of this program is to understand the physical mechanisms which mediate the fluxes of energy, momentum, and matter between the air and sea. In particular, the form and dynamics of mixed layer motion can have a significant effect on these exchanges, and we hope to improve our ability to describe and predict these motions and their effects. SCIENTIFIC OBJECTIVES. The immediate objective of this program was to document in some detail the motion at the surface over a variety of conditions, and relate this, together with the evolution of the mixed layer depth, to the measurable forcing terms (wind, waves, inertial currents, heat-flux, and stratification). APPROACH. A Phased-Array Doppler Sonar (PADS) was deployed on the Research Platform FLIP off Pt. Conception in the spring of 1995, as part of MBLEX, an experiment aimed at improving our understanding of the Marine Boundary Layers on both side of the air/sea interface. A second was completed in time for the second leg of MBLEX, off Monterey CA. This instrument provides estimates of the radially-directed component of velocity over an area up to 400m radius by 35 degrees in azimuth. The spatial resolution is about 8 m in range by 3 degrees; so (for example) at 200m range the sample area is about 8 by 10 meters. The sonars transmitted every 0.75s, with each ping simultaneously sampling over all angles; thus surface waves as well as the mean flow are resolved in the raw data. 30s averages (40 pings) were recorded, providing about 3 cm/s RMS velocity error in each range-angle bin (in practice, additional errors arise from imperfect beamforming, etc.).
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 30, 1997
- Accession Number
- ADA634183
Entities
People
- Jerome A. Smith
Organizations
- Scripps Institution of Oceanography