Dataset: CTD_fv
Deployment: SC9802

Fishing vessel CTD data, Gulf of Maine, 1998

Co-Principal Investigator:

Frank Bub (University of New Hampshire, UNH/OPAL)

Ann Bucklin (University of New Hampshire, UNH/OPAL)

James P. Manning (Northeast Fisheries Science Center - Woods Hole, NOAA NEFSC)

BCO-DMO Data Manager:

Ms Dicky Allison (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

U.S. GLOBEC Georges Bank (GB)

Data URL:

https://osprey.bco-dmo.org/dataset-deployment/449939/data

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Description

The UNH SeaBird SBE-25 SeaLogger measures:

Temperature (degrees C) with a SeaBird SBE-3F.
Conductivity (Siemens/m) with a SeaBird SBE-4C.
Pressure (decibars) with a SBE 29 strain gage sensor.
Percent light transmission with a Wet Labs CST-126R transmissometer across a 25 cm distance at the red light wavelength 660 nm. Data are presented as a percentage relative to pure water.
Chlorophyll concentration in micrograms/liter with a Wet Labs WETStar Fluorometer model 9607003.
PAR (photosynthetically active radiation) with a Biospherical QPS-200PD which observes an upper hemispherical total irradiance in quanta/sq-cm/sec.
Dissolved oxygen with a SBE-23Y (Yellow Springs Instrument) in milliliters/liter.

During a cast, sensors are flushed with a SBE-5T pump at approximately 25 ml/s. The system samples and stores all data at 8 Hz (8 samples/ second). Profiling rates should be 20 meters/minute for an average of 24 samples/1 m pressure level. Normally only the downcasts are analyzed (unless a problem is noted). Sensors are factory calibrated annually.

Derived data are calculated using Matlab and/or UNH algorithms developed in accordance with standards prescribed by Fofonoff and Millard, 1983.

For additional information about the SC9801 cruise see the NOAA Coastal Ocean Program Progress Report

Additional data processing notes were provided by the contributor. Note: These notes reflect the CTD processing steps for data collected during the UNH CONVEX progam. However, they are indicative of the processing performed on the data reported here. Parameter names have been changed to agree with GLOBEC requirements.

Methods & Sampling

Dataset acquisition description

The UNH SeaBird SBE-25 SeaLogger measures:

Temperature (degrees C) with a SeaBird SBE-3F.
Conductivity (Siemens/m) with a SeaBird SBE-4C.
Pressure (decibars) with a SBE 29 strain gage sensor.
Percent light transmission with a Wet Labs CST-126R transmissometer across a 25 cm distance at the red light wavelength 660 nm. Data are presented as a percentage relative to pure water.
Chlorophyll concentration in micrograms/liter with a Wet Labs WETStar Fluorometer model 9607003.
PAR (photosynthetically active radiation) with a Biospherical QPS-200PD which observes an upper hemispherical total irradiance in quanta/sq-cm/sec.
Dissolved oxygen with a SBE-23Y (Yellow Springs Instrument) in milliliters/liter.

Deployment-specific acquisition description

The UNH SeaBird SBE-25 SeaLogger measures:

Temperature (degrees C) with a SeaBird SBE-3F.
Conductivity (Siemens/m) with a SeaBird SBE-4C.
Pressure (decibars) with a SBE 29 strain gage sensor.
Percent light transmission with a Wet Labs CST-126R transmissometer
across a 25 cm distance at the red light wavelength 660 nm. Data
are presented as a percentage relative to pure water.
Chlorophyll concentration in micrograms/liter with a Wet Labs WETStar
Fluorometer model 9607003.
PAR (photosynthetically active radiation) with a Biospherical
QPS-200PD which observes an upper hemispherical total irradiance
in quanta/sq-cm/sec.
Dissolved oxygen with a SBE-23Y (Yellow Springs Instrument) in
milliliters/liter.

During a cast, sensors are flushed with a SBE-5T pump at approximately
25 ml/s. The system samples and stores all data at 8 Hz (8 samples/
second). Profiling rates should be 20 meters/minute for an average of
24 samples/1 m pressure level. Normally only the downcasts are analyzed
(unless a problem is noted). Sensors are factory calibrated annually.

Data Processing Description

Dataset Processing Description

Derived data are calculated using Matlab and/or UNH algorithms developed in accordance with standards prescribed by Fofonoff and Millard, 1983.

Deployment-specific processing description

<p>

Note: The Brunt-Vaisala Frequency (N-squared) data were
reprocessed by Frank Bub with raw data calculated over 1 m
intervals, rather than smoothed over 5 m bins. The 5 m bins did not
work well with inshore profiles. Negative numbers indicate
instability. Use data with caution.
</p>
<p>
Derived data are calculated using Matlab and/or UNH algorithms developed
in accordance with standards prescribed by Fofonoff and Millard, 1983.

</p>

More information about this dataset deployment

Funding

Award Number	Funding Source
unknown GB NOAA	National Oceanic and Atmospheric Administration
unknown GB NSF	National Science Foundation

Instruments

Sea-Bird SBE 25 Sealogger CTD

Supplied Name: CTD Seabird 25

Supplied Description:

The UNH SeaBird SBE-25 SeaLogger measures - Temperature (degrees C) with a SeaBird SBE-3F. Conductivity (Siemens/m) with a SeaBird SBE-4C. Pressure (decibars) with a SBE 29 strain gage sensor. Percent light transmission with a Wet Labs CST-126R transmissometer across a 25 cm distance at the red light wavelength 660 nm. Data are presented as a percentage relative to pure water. Chlorophyll concentration in micrograms/liter with a Wet Labs WETStar Fluorometer model 9607003. PAR (photosynthetically active radiation) with a Biospherical QPS-200PD which observes an upper hemispherical total irradiance in quanta/sq-cm/sec. Dissolved oxygen with a SBE-23Y (Yellow Springs Instrument) in milliliters/liter.During a cast, sensors are flushed with a SBE-5T pump at approximately 25 ml/s. The system samples and stores all data at 8 Hz (8 samples/ second). Profiling rates should be 20 meters/minute for an average of 24 samples/1 m pressure level. Normally only the downcasts are analyzed (unless a problem is noted). Sensors are factory calibrated annually.

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.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
cruiseid	cruise identification, i.e. SC9801		no_bcodmo_term
si	scientific investigator's name		no_bcodmo_term
station	station number		station
lat	latitude, negative = South	decimal degrees	lat
lon	longitude, negative = West	decimal degrees	lon
time_gmt	time, at bottom of cast	HHmm, GMT	time_gmt
day_gmt	day of month	GMT	day_gmt
month_gmt	month of year	GMT	month_gmt
year	year	GMT	year
depth_w	depth of water	meters	depth_w
nbin	number of data cycles per press/bin average		nbin
press	depth of sample as pressure	decibars	press
temp	temperature	degrees centigrade	temp
sal	salinitiy	PSU	sal
sigma_0	sigma-theta, potential density	kilograms/meter³	sigma_0
depth	sample depth	decimal meters	depth
potemp	potential temperature	degrees centigrade	potemp
cond	conductivity	siemens/meter	cond
light_trans	light transmission, using a transmissometer	per cent	no_bcodmo_term
fluor	fluorescence, chlorophyll conc.	micrograms/liter	fluor
par_scalar	photosynthetically active radiation, scalar (400-700nm)	microEinsteins/second/meter²	par_scalar
o2	dissolved oxygen	milliliters/liter	O2
bvfq	Brunt-Vaisaila Frequency (N-squared)	1/second²	bvfq
dynh_0	dynamic height, ref. to surface	meters	dynh_0
sound_vel			sound_vel

Database

Contribute Data

Dataset: CTD_fv
Deployment: SC9802

Dataset acquisition description

Deployment-specific acquisition description

Dataset Processing Description

Deployment-specific processing description

Database

Contribute Data

Dataset: CTD_fvDeployment: SC9802

Dataset acquisition description

Deployment-specific acquisition description

Dataset Processing Description

Deployment-specific processing description

Dataset: CTD_fv
Deployment: SC9802