Dataset: CTD - TRANSPORT Mapping Cruises
Deployment: BT-12-02

CTD data from TRANSPORT Mapping cruises, 2010-2012, Choptank River.

Principal Investigator:

Elizabeth North (University of Maryland Center for Environmental Science, UMCES/HPL)

BCO-DMO Data Manager:

Shannon Rauch (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

Integrating field methods and numerical models to quantify the links between larval transport, connectivity, and population dynamics (TRANSPORT)

Current State:

Final no updates expected

Version:

17 Jan 2014

Deployment Synonyms:

2012.02

Version Date:

2014-01-17

Data URL:

https://www.bco-dmo.org/dataset-deployment/476278/data

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Description

CTD data from a series of one-day research cruises on the Choptank River (Chesapeake Bay, USA) during May to September of 2010 to 2012.

Methods & Sampling

Dataset acquisition description

Each cruise took place on the R/V Terrapin, a 26-ft Parker with a 275 mercury outboard equipped with a davit, operated by UMCES. On each cruise, several sampling stations were occupied. A CTD cast was made at each station, and the downcast was used to measure water properties. The CTD equipped with a fluorometer, OBS, dissolved oxygen and PAR sensors. Using hoses attached to the CTD frame, bivalve larvae were collected from near bottom to the surface by moving the CTD up through the water column. Water samples were collected for chl-a pigment (using a syringe/filter apparatus) to calibrate the fluorometer and for total suspended solids (using a water bottle provided by Analytical Services).

Data Processing Description

Dataset Processing Description

CTD Processing:
The SBEDataProcessing package of SeasoftV2 software was used for CTD Processing.

CTD Processing Overview; 4 steps:
(1) Data Conversion – converts the raw hex data to engineering units;
(2) Align CTD – aligns the Oxygen Voltage data with an appropriate advance time;
(3) Bin Average – averages the variables over bins of the specified size;
(4) ASCII Out – creates text files that can be read by other programs.

For more details, see the CTD Metadata for the 2010-2012 TRANSPORT Mapping Cruises (PDF).

TSS and chl_a were calculated using the following equations:
2010 Data:
TSS May/June:          y = 1.3396x + 24.35 where x = OBS_NTU..
TSS July/Aug/Sept:   y = 1.6991x + 26.139 where x = OBS_NTU.
chl_a May/June:         y = 26.527x - 2.7618 where x = voltage (V4).
chl_a July/Aug/Sept: y = 22.251x + 0.8101 where = voltage (V4).

2011 Data:
TSS May/June:          y = 1.5307x + 1.7239 where x = OBS_NTU.
TSS July/Aug/Sept:   y = 1.5087x + 4.6136 where x = OBS_NTU.
chl_a May/June:       y = 8.1264x + 5.8107 where x = voltage (V4).
chl_a July/Aug/Sept: y = 12.328x + 0.3111 where x = voltage (V4).

2012 Data:
TSS May/June:          y = 1.5049x + 2.284 where x = OBS_NTU.
TSS July/Aug/Sept:   y = 1.2666x + 6.3753 where x = OBS_NTU.
chl_a May/June:         y = 10.387x + 0.315 where x = voltage (V4).
chl_a July/Aug/Sept: y = 17.801x - 3.1581 where x = voltage (V4).

BCO-DMO Processing:
- Modified parameter names;
- Replaced '-9.99e-29' with 'nd' ('no data').

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-0829512	NSF Division of Ocean Sciences

Instruments

D&A Instruments Optical Backscatter Sensor OBS-3

Supplied Name: OBS

Supplied Description:

Equipped on the CTD.

Instrument Type

Generic Name: D&A Instruments Optical Backscatter Sensor OBS-3

Acronym: OBS-3

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0579/

Generic Description:

Optical backscatter instrument measuring scattering in water between 140 - 160 deg for a wavelength of 875nm. It has a turbidity range of 0-2000 FTU and a maximum working depth of 500m. This instrument was superseded by the OBS-3+ model in 2005. The D and A Instrument Company and its OBS product line were purchased by Campbell Scientific Inc who now has full responsibility for D and A Instruments.

LI-COR Biospherical PAR Sensor

Supplied Name: Biospherical/LI-COR PAR Sensor

Supplied Description:

Equipped on the CTD.

Instrument Type

Generic Name: LI-COR Biospherical PAR Sensor

Acronym: LI-COR Biospherical PAR

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0074/

Generic Description:

The LI-COR Biospherical PAR Sensor is used to measure Photosynthetically Available Radiation (PAR) in the water column. This instrument designation is used when specific make and model are not known.

Sea-Bird SBE 25 Sealogger CTD

Supplied Name: SBE25 SEALOGGER CTD

Supplied Description:

An SBE25 SEALOGGER CTD, made by Sea-Bird Electronics, was used. It was equipped with a fluorometer (WET Labs WETstar), an Optical Backscatter Sensor (OBS, D & A), dissolved oxygen (SBE 43) and PAR (Biospherical/Licor) sensors. Because of the plumbing system on the CTD, there is delay between the dissolved oxygen/fluorometery readings and the pressure sensor.

Instrument Type

Generic Name: Sea-Bird SBE 25 Sealogger CTD

Acronym: CTD SBE 25

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0040/

Generic Description:

The Sea-Bird SBE 25 SEALOGGER CTD is battery powered and is typically used to record data in memory, eliminating the need for a large vessel, electrical sea cable, and on-board computer. All SBE 25s can also operate in real-time, transmitting data via an opto-isolated RS-232 serial port. Temperature and conductivity are measured by the SBE 3F Temperature sensor and SBE 4 Conductivity sensor (same as those used on the premium SBE 9plus CTD). The SBE 25 also includes the SBE 5P (plastic) or 5T (titanium) Submersible Pump and TC Duct. The pump-controlled, TC-ducted flow configuration significantly reduces salinity spiking caused by ship heave, and in calm waters allows slower descent rates for improved resolution of water column features. Pressure is measured by the modular SBE 29 Temperature Compensated Strain-Gauge Pressure sensor (available in eight depth ranges to suit the operating depth requirement). The SBE 25's modular design makes it easy to configure in the field for a wide range of auxiliary sensors, including optional dissolved oxygen (SBE 43), pH (SBE 18 or SBE 27), fluorescence, transmissivity, PAR, and optical backscatter sensors. More information from Sea-Bird Electronics: http:www.seabird.com.

Sea-Bird SBE 43 Dissolved Oxygen Sensor

Supplied Name: SBE-43

Supplied Description:

Equipped on the CTD.

Instrument Type

Generic Name: Sea-Bird SBE 43 Dissolved Oxygen Sensor

Acronym: SBE-43 DO

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0036/

Generic Description:

The Sea-Bird SBE 43 dissolved oxygen sensor is a redesign of the Clark polarographic membrane type of dissolved oxygen sensors. more information from Sea-Bird Electronics

WET Labs (Sea-Bird WETLabs) WETStar fluorometer

Supplied Name: WETLabs WETStar Fluorometer

Supplied Description:

Equipped on the CTD.

Instrument Type

Generic Name: WET Labs (Sea-Bird WETLabs) WETStar fluorometer

Acronym: WETStar

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0075/

Generic Description:

Submersible fluorometer designed for through-flow or pumped CTD applications manufactured by WetLabs and which can be configured for various types of fluorescence. The probe has a temperature range of 0-30 degrees C and a depth rating of 600 meters.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
year	4-digit year.	YYYY	year
cruise_id	Cruise identification number.	dimensionless	cruise_id
station	Identification number of the sampling station.	dimensionless	station
lat	Latitude of the sampling station.	decimal degrees	lat
lon	Longitude of the sampling station.	decimal degrees	lon
month	Month (1-12) of year. Local time (EDT).	dimensionless	month
day	Day (1-31) of month. Local time (EDT).	dimensionless	day
time_local	Local time (EDT) as hours and minutes; 24-hour clock.	HHMM	time_local
depth	Sample depth.	meters	depth
sal	Salinity.	Practical Salinity Units (PSU)	sal
temp	Water temperature.	degrees Celsius	temp
cond	Conductivity.	milli-Siemens per centimeter (mS/cm)	cond
density	Density.	kilograms per cubic meter (kg/m3)	density
fluor	Fluorescence.	milligrams per cubic meter (mg/m3)	fluor
O2_mgL	Dissolved oxygen.	milligrams per liter (mg/L)	O2_mg_L
O2_sat_pcnt	Percent dissolved oxygen saturation.	percent (%)	O2_sat_pcnt
OBS_NTU	Turbidity measured by Optical Backscatter Sensor (OBS).	Nephelometric Turbidity Units (NTU)	no_bcodmo_term
PAR	PAR.	microEinsteins per second per square meter (uE/sec/m^2)	PAR
TSS	Total suspended solids (see 'Processing Description' for equations used).	milligrams per liter (mg/L)	no_bcodmo_term
chl_a	Chlorophyll-a (see 'Processing Description' for equations used).	micrograms per liter (ug/L)	chl_a
V4	Fluorometer voltage; used in calculation of chl_a.	volts	flvolt
V1	OBS voltage.	volts	no_bcodmo_term
scan	CTD scan number.	dimensionless	scan
nbin	Number of data cycles used to compile an average value for a given depth/BIN interval.	dimensionless	nbin
flag	Flag.	dimensionless	flag
ISO_DateTime_Local	Date and time (in local EDT time zone) formatted to ISO 8601 standard. T indicates start of time string.	YYYY-mm-ddTHH:MM:SS.ss	ISO_DateTime_Local

Database

Contribute Data

Dataset: CTD - TRANSPORT Mapping Cruises
Deployment: BT-12-02

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: CTD - TRANSPORT Mapping CruisesDeployment: BT-12-02

Dataset acquisition description

Dataset Processing Description

Dataset: CTD - TRANSPORT Mapping Cruises
Deployment: BT-12-02