Dataset Submitted

Eastern Gulf of Mexico Glider Deployment M69 (01/03/17 – 01/13/17) – Echosounder Water Column Backscatter Intensity

Authors: Chad Lembke, David Mann, Susan Lowerre-Barbieri, Chris Taylor, Steven Murawski
Identified On: Mar 06 2017 22:41 UTC
DOI: https://doi.org/10.7266/n7-4skm-bj34
UDI: FL.x707.000:0007
Project Information

Funded By:
Florida RESTORE Act Centers of Excellence Program

Funding Cycle:
FLRACEP 1

Research Group:
Demonstration of Fisheries Assessment Applications for Underwater Gliders

Point of Contact

Chad Lembke
University of South Florida / College of Marine Science
clembke@usf.edu

Data Collection Period
2017-01-03
to
2017-01-13
Theme keywords

Underwater glider, Water column acoustics

Abstract:

A Slocum Glider was deployed in the eastern Gulf of Mexico off of Tampa Bay in January 2017. As the glider traverses its transit path, it makes measurements at various depths from ~2m to near the seafloor or up to 200m. While the glider is deployed at sea, it surfaces and communicates to an onshore control station at predetermined intervals. A decimated selection of vehicle and science measurement is transmitted during these surface transmissions, and the relevant data becomes available through a USF web site. After the glider’s recovery at the end of the deployment, much of the complete measurement suite is downloaded from the vehicle and processed, and also becomes available through the USF site as well as a national data archive. The measurements in this data set include echosounder water column backscatter intensity. Other data sets for this deployment include environmental water quality parameters, acoustic tag telemetry receiver detections, and passive acoustic recordings. The glider was deployed on January 3, 2017 at the 30m isobath. It attempted to transit NW along the Gulfstream Natural Gas Pipeline, however currents to the south prevented significant northward progress and eventually pushed the glider well to the south. It was recovered well south of Tampa Bay off of Longboat Key on January 13, 2017.

Suggested Citation:

Chad Lembke, David Mann, Susan Lowerre-Barbieri, Chris Taylor, Steven Murawski. Eastern Gulf of Mexico Glider Deployment M69 (01/03/17 – 01/13/17) – Echosounder Water Column Backscatter Intensity. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-4skm-bj34

Purpose:

Collection of water column biomass using underwater glider.

Data Parameters and Units:

Echosounder water column backscatter intensity

Methods:

Based on echosounder results, water column biomass was calculated based the Nautical Area Scattering Coefficient. The NASC calculation is the sum of all backscatter in an ensonified volume (in our case, the watercolumn under the glider (excluding the seabed) along a length of travel (I think 100m?), translated to the surface area sampled (2D). The Nautical Area converts to units of scattering per square nautical mile (instead of per square meter).

Instruments:

ASL Environmental AZFP w/ 200kHz transducer.