Assessing the Impact of Tides and Atmospheric Fronts on Submesoscale Physical and Bio-Optical Distributions Near a Coastal Convergence Zone
Abstract
Optically-active constituents vary over short time and space scales in coastal waters, and they are impacted by a variety of complex, inter-related forcing processes. As part of the Integrated Coastal Bio-Optical Dynamics (ICoBOD) project, we conducted a field campaign in Mississippi Sound in the northern Gulf of Mexico during spring 2018 to examine the impact of the passage of atmospheric and tidal fronts on fine-scale physical and bio-optical property distributions in a shallow, dynamic, coastal environment. During a 25-day experiment, we deployed eight moorings over a roughly 7 x 7 km box encompassing a frontal zone, to collect a time series of physical and bio-optical measurements. We describe changes in diver visibility related to the passage of a short-duration, high-turbidity surface plume and nepheloid layer development/decay during a tidal cycle. Maximum nepheloid layer development was observed during low tide and lasted about 9-12 h. The strongest turbidity signal extended about 4-5 m above the bottom (approximately half of the water column), although anomalously elevated values were observed all the way to the surface. In addition, high-resolution (50 m) hydrodynamic model simulations provide insight into the frontal dynamics and aid interpretation of the observed patterns. Mooring observations confirmed model-predicted heat flux changes associated with the passage of an atmospheric cold front.
Document Details
- Document Type
- Technical Report
- Publication Date
- Feb 07, 2020
- Accession Number
- AD1095703
Entities
People
- David Wei Chi Wang
- Geoffrey B. Smith
- H. W. Wijesekera
- Igor G. Shulman
- M. D. Lewis
- Richard Jr W. Gould
- Stephanie C. Anderson
- Travis A. Smith
- W. D. Miller
Organizations
- United States Naval Research Laboratory