The observations at these nine locations are part of a collaborative effort designed to understand the physical processes that control the transport of sediments in Long Bay, South Carolina. The observations document changes in water flow, sea level, conductivity, temperature,surface wave characteristics, near-bottom turbulence, suspended sediment concentrations, and sea floor bedforms (ripples) in Long Bay. They also provide observations for testing numerical models of circulation.
This data report presents a description of the study background, a description of the field program, instrumentation, and data processing and archival techniques, and all observational data. The objective of this report is to make the data available in digital form and to provide information to facilitate further analysis of the data. The edited data are presented in time series plots for rapid visualization of the data set, and in data files which are in NetCDF format. Harmonic analysis of the observations is also included to describe the tidal characteristics of Long Bay. Standard meteorological data and river discharge data, obtained from other offices and agencies, are also provided to describe the climatologic and hydrologic characteristics of the region.
John Warner and George Voulgaris were co-chief scientists on the cruises. Fran Lightsom oversaw and processed the time series data. Charlene Sullivan wrote most of the Matlab scripts, made all of the plots and calculations, and assembled the data report. We thank the captains and crews of the R/V Dan Moore for their outstanding logistical support for this field measurement program. A collaborative effort with the United States Geological Survey, the University of South Carolina, and Georgia Institute of Technology Savannah safely conducted three cruises to deploy and recover individual instruments on 26 moorings to obtain this data set. Marinna Martini, Jonathan Borden, and Stephen Ruane oversaw the preparation and deployment of the physical oceanographic instrumentation. John Warner, George Voulgaris, and Marinna Martini took most of the photographs in this report. Divers located the tripods on the sea floor and attached/detached retrieval cables to the surface buoys.
Instruments to measure water flow, sea level, conductivity, temperature, surface wave characteristics, near-bottom turbulence, suspended sediment concentrations, and sea floor bedforms (ripples) were deployed and recovered at nine locations in Long Bay, South Carolina from October 2003 through April 2004.
Instrumentation was recovered and replaced at each location once during the deployment period in late January 2004. The instruments were deployed and recovered aboard the R/V Dan Moore, a research vessel owned and operated by Cape Fear Community College in Wilmington, North Carolina.
DATA PROCESSING
Data processing was conducted using the proprietary software for each instrument, and (or) specialized software developed by the USGS. The proprietary software was often used to download data from the instruments and export the data to ASCII-files. Post-processing of the raw binary or ASCII files was accomplished using USGS software developed in the MatlabŪ (http://www.mathworks.com/) programming language. Most MatlabŪ M-files used for post-processing are available via the World Wide Web (WWW) (links provided). Those that are not available via the WWW are included in this report (see the MatlabŪ m-files page).
Data were first decoded and calibrated from instrument-specific formats and units to the EPIC-standard NetCDF format (http://www.pmel.noaa.gov/epic/) and scientific units. Data were carefully checked for instrument malfunctions and then edited. The beginning and end of each data series were truncated to remove data collected out of water. The data were carefully checked at each stage of processing. After final editing, the best basic version of the data file includes all variables recorded at the basic sampling interval. Best basic versions of all data files in NetCDF format are included in this report.
These data have been edited to remove wild points and data recorded when the instruments were out of the water before and after deployment.
Biological fouling often degrades acoustical and optical data after several months of deployment. Organisms grow on the instrument transducers and gradually block acoustical pulses and light transmission, which results in a gradual upward drift of the beam attenuation coefficient. Care has been exercised to remove most data that has been affected by biofouling.
Significant tilt of the ADCP at Site 5 resulted in complete data loss for that site. All data should be used and interpreted with care.
Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government.