Dataset: Along-stream flux per unit width (station B Aquadopp)

Name: Along-stream flux per unit width at station B located at an oyster reef in Wassaw Sound, Georgia in November of 2014 (SensoryNCE project)
Published: 2018-07-12
Keywords: oceans

Cite This Dataset

Spatial Extent: N:31.9199 E:-81.1392 S:31.9199 W:-81.1392

Temporal Extent: 2014-11-03 - 2014-11-06

Project:

The role of the sensory environment and predator chemical signal properties in determining NCE strength in cascading interactions on oyster reefs (SensoryNCE)

Principal Investigator:

Marc Weissburg (Georgia Institute of Technology, GA Tech)

Co-Principal Investigator:

Julia Kubanek (Georgia Institute of Technology, GA Tech)

Donald Webster (Georgia Institute of Technology, GA Tech)

Contact:

Donald Webster (Georgia Institute of Technology, GA Tech)

BCO-DMO Data Manager:

Amber D. York (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Version:

Version Date:

2018-07-12

Restricted:

Validated:

Yes

Current State:

Final no updates expected

Along-stream flux per unit width at station B located at an oyster reef in Wassaw Sound, Georgia in November of 2014 (SensoryNCE project)

Expand/Collapse All

Description

This dataset contains data from an Aquadopp current profiler stationed station B, located at an oyster reef in Wassaw Sound, Georgia from November 3rd to 6th, 2014. The data include pressure, temperature, streamwise flux, cross-stream flux, and vertical flux.

These data were published in Young et al., 2016 (see Fig. 5) :

In addition to the "Get data" button above which provides various options to download the data in ASCII format, the originally submitted data in MATLAB .mat format (SensorAndRotatedQ_Filt123Q_30sec.mat, 199 KB)

Methods & Sampling

The equipment used is a current profiler (Nortek Aquadopp HR-profiler). The Aquadopp measures the flow velocity in a series of evenly-spaced vertical bins. The Aquadopp measurements have a resolution of 3 mm/s and were collected continuously at 1 Hz. The Aquadopp returned the velocity within 10 cm vertical bins, equally spaced from 0.3 to 2.2 m above the instrument.

Sampling Location Map:

Image courtesy of David Young

Data Processing Description

Dry bins were identified using the built-in PT and temperature gauges to estimate the water depth above the instrument. All bins in which the water depth had not reached at least the midpoint of the next highest bin were discarded. The velocity measurements in each bin were averaged over 30 sec intervals to smooth out turbulent velocity fluctuations. The flux-per-unit-width (q) was estimated by summing the velocity in each bin multiplied by the bin height. Flux-per-unit-width therefore corresponded to the fluid flow through a vertical line extending from the Aquadopp to the surface. An ellipse was fit to a scatter plot of the measured east and north flux components for each Aquadopp, and the major axis of the resulting ellipse was defined as the “along-stream” flow direction. Correspondingly, the minor axis is defined as the “cross-stream” direction. The horizontal flux vector was rotated to correspond to the defined along-stream and cross-stream directions.

BCO-DMO Data Manager Processing Notes:
* added a conventional header with dataset name, PI name, version date
* data extracted from MATLAB .mat files to ASCII flat files to serve in the BCO-DMO system
* modified parameter names to conform with BCO-DMO naming conventions
* added approximate lat and lon of sampling location to data
* Time format changed from matlab datenum to Date and Time (yyyy-mm-dd,HH:MM:SS)
* Data version 2 (2018-07-12) replaces data version 1 (2017-07-20) - improved metadata, added timestamp in UTC in addition to local date/time

Data Files

File
Flux_B.csv (Comma Separated Values (.csv), 578.03 KB) MD5:8abeadddb7b9f49ce2dea396a8e79001 Primary data file for dataset ID 709402

More Information about this dataset

Funding Sources

Funding Source	Award Number
NSF Division of Ocean Sciences	OCE-1234449

Deployments

Deployment	Synonyms	Start Date	Platform	Investigator
SensoryNCE_2014	RoseDhu11.03.2014	2014-11-03	Wassaw_Sound_GA	Marc Weissburg (Principal Investigator)	data info

Instruments

Acoustic Doppler Current Profiler

Supplied Name: Nortek Aquadopp HR-profiler

Supplied Description:

current profiler (Nortek Aquadopp HR-profiler).

Instrument Type

Generic Name: Acoustic Doppler Current Profiler

Acronym: ADCP

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/115/

Generic Description:

The ADCP measures water currents with sound, using a principle of sound waves called the Doppler effect. A sound wave has a higher frequency, or pitch, when it moves to you than when it moves away. You hear the Doppler effect in action when a car speeds past with a characteristic building of sound that fades when the car passes. The ADCP works by transmitting "pings" of sound at a constant frequency into the water. (The pings are so highly pitched that humans and even dolphins can't hear them.) As the sound waves travel, they ricochet off particles suspended in the moving water, and reflect back to the instrument. Due to the Doppler effect, sound waves bounced back from a particle moving away from the profiler have a slightly lowered frequency when they return. Particles moving toward the instrument send back higher frequency waves. The difference in frequency between the waves the profiler sends out and the waves it receives is called the Doppler shift. The instrument uses this shift to calculate how fast the particle and the water around it are moving. Sound waves that hit particles far from the profiler take longer to come back than waves that strike close by. By measuring the time it takes for the waves to bounce back and the Doppler shift, the profiler can measure current speed at many different depths with each series of pings. (More from WHOI instruments listing).

Parameters

Date and time formats are described in python strftime() syntax.

Supplied Name	Supplied description	Supplied Units	Standard Name
date	Date (local EST) in format yyyy-mm-dd	unitless	date
time	Time (local EST) in format HH:MM:SS	unitless	time
pressure	Aquadopp pressure	dBar	press
temperature	Aquadopp temperature	degrees C	temp
streamwise_flux	Stream-wise flux	m3/s per m	no_bcodmo_term
cross_stream_flux	Cross-steram flux	m3/s per m	no_bcodmo_term
vertical_flux	Vertical flux	m3/s per m	no_bcodmo_term
lat_approx	Approximate latitude	decimal degrees	lat
lon_approx	Approximate longitude	decimal degrees	lon
ISO_DateTime_UTC	Timestamp (UTC) in standard ISO 8601:2004(E) format YYYY-mm-ddTHH:MM:SSZ	unitless	ISO_DateTime_UTC

Status message

Database

Contribute Data

Dataset: Along-stream flux per unit width (station B Aquadopp)