Metadata Report for BODC Series Reference Number 1147860
Metadata Summary
Problem Reports
Data Access Policy
Narrative Documents
Project Information
Data Activity or Cruise Information
Fixed Station Information
BODC Quality Flags
SeaDataNet Quality Flags
Metadata Summary
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Problem Reports
No Problem Report Found in the Database
RSS James Clark Ross Cruise JR20130109/JR274 CTD Data Quality Document
Cast76s contains some anomalous data for several of the channels such as chlorophyll and oxygen concentration, therefore the data should be used with caution.
Attenuance (ATTNDR01)
Attenuance data are only available from the stainless steel CTD casts.
Downwelling Irradiance (DWIRPP01)
These profiles are only available for the titanium CTD casts. Many of the profiles are constant with values of zero. Casts CTD39t and CTD48t were deployed at night in the dark so values of zero would be expected. All other casts with consistant values of zero however, were not deployed in the dark and so have been flagged as suspect. Several of the series have data points that are beyond the acceptable range of the parameter (0-500 W m-2). These data points have been flagged as suspect.
Downwelling Irradiance (IRRDUV01)
Several of the series have data points that are beyond the acceptable range of the parameter (0-2500 µE m-2s-1). These data points have been flagged as suspect.
Chlorophyll concentration (CPHLPM01)
Several of the series have data points that are beyond the acceptable range of the parameter (0-999 mg m-3). These data points have been flagged as suspect.
Oxygen concentration (DOXYSC01 and DOXYSU01)
Several of the series have data points that are beyond the acceptable range of the parameter (0-600 µmol L-1). These data points have been flagged as suspect.
Data Access Policy
Public domain data
These data have no specific confidentiality restrictions for users. However, users must acknowledge data sources as it is not ethical to publish data without proper attribution. Any publication or other output resulting from usage of the data should include an acknowledgment.
The recommended acknowledgment is
"This study uses data from the data source/organisation/programme, provided by the British Oceanographic Data Centre and funded by the funding body."
Narrative Documents
Sea-Bird Dissolved Oxygen Sensor SBE 43 and SBE 43F
The SBE 43 is a dissolved oxygen sensor designed for marine applications. It incorporates a high-performance Clark polarographic membrane with a pump that continuously plumbs water through it, preventing algal growth and the development of anoxic conditions when the sensor is taking measurements.
Two configurations are available: SBE 43 produces a voltage output and can be incorporated with any Sea-Bird CTD that accepts input from a 0-5 volt auxiliary sensor, while the SBE 43F produces a frequency output and can be integrated with an SBE 52-MP (Moored Profiler CTD) or used for OEM applications. The specifications below are common to both.
Specifications
Housing | Plastic or titanium |
Membrane | 0.5 mil- fast response, typical for profile applications 1 mil- slower response, typical for moored applications |
Depth rating | 600 m (plastic) or 7000 m (titanium) 10500 m titanium housing available on request |
Measurement range | 120% of surface saturation |
Initial accuracy | 2% of saturation |
Typical stability | 0.5% per 1000 h |
Further details can be found in the manufacturer's specification sheet.
Instrument Description JR20130109 Stainless Steel Frame
Standard Rosette CTD Unit and Auxiliary Sensors
Two CTD systems were used during this cruise; a stainless steel frame and a titanium frame. This document outlines the instrument description of the stainless steel frame.
A 24-way stainless steel frame (s/n SBE CTD6), with a Sea-Bird 9 plus CTD underwater unit (SN 09P-30856-0707) and SBE 11 plus deck unit (s/n 11P-20391-0502) was used throughout the cruise. All auxiliary instruments were attached to a Sea-Bird 32 24-way carousel (s/n 32-46833-0636) with Ocean Test Equipment 20L water samplers (s/n 1A -12A, 15A-21A, 24A, 26A, 34A, 45A, 47A).
The table below provides further information on the CTD sensors.
Sensor | Model | Serial Number | Calibration | Comments |
---|---|---|---|---|
CTD Underwater Unit | SBE 9plus | 09P-30856-0707 | 22/08/2012 | - |
Pressure transducer | Paroscientific Digiquartz temperature compensated pressure sensor | 89973 | 22/08/2012 | - |
Primary Conductivity sensor | SBE 4C | 4C-4126 | 12/04/2012 | Primary sensor |
Secondary Conductivity sensor | SBE 4C | 4C-4087 | 12/04/2012 | Secondary sensor |
Primary Temperature sensor | SBE 3P | 3P-5623 | 13/04/2012 | Primary sensor |
Secondary Temperature sensor | SBE 3P | 3P-5645 | 12/04/2012 | Secondary sensor |
Dissolved oxygen | SBE 43 | 43-2290 | 31/03/2012 | - |
Fluorometer | Chelsea Technologies Group MKIII Aquatracka fluorometer | 12-8513-003 | 15/06/2012 | - |
Transmissometer | WETLabs C-Star transmissometer | CST-527DR | 06/09/2012 | - |
Photosynthetically Active Radiation | Biospherical QCP2300-HP PAR irradiance sensor, DWIRR | 70441 | 16/05/2012 | - |
Altimeter | Tritech PA200 altimeter | 244739 | 09/05/2012 | - |
Instrument Description JR20130109 Titanium Frame
Standard Rosette CTD Unit and Auxiliary Sensors
Two CTD systems were used during this cruise; a stainless steel frame and a titanium frame. This document outlines the instrument description of the titanium frame.
The Titanium CTD system used an 11 plus deck unit (s/n 11P-20391-0502) with SBE 9plus underwater unit (s/n 09P-39607-0803). A 24-way titanium frame (s/n SBE CTD TITA1), with secondary temperature and conductivity sensors was used throughout the cruise. All other instruments were attached to a Sea-Bird 32 24-way carousel (for casts 001t through 045t, s/n 32-24680-0346; for casts 048t through 077t, s/n 32-34173-0493), with Ocean Test Equipment 10L TMF water samplers (s/n 1T through 24T).
The table below provides further detail on the sensors included in the CTD unit.
Sensor | Model | Serial Number | Calibration | Comments |
---|---|---|---|---|
CTD Underwater Unit | SBE 9plus | 09P-39607-0803 | 12/05/2011 | - |
Pressure transducer | Paroscientific Digiquartz temperature compensated pressure sensor | 93896 | 12/05/2011 | - |
Primary Conductivity sensor | SBE 4C | 4C-2165 | 21/08/2012 | Primary sensor |
Secondary Conductivity sensor | SBE 4C | 4C-3272 | 04/09/2012 | Secondary sensor |
Primary Temperature sensor | SBE 3P | 3P-4381 | 04/09/2012 | Primary sensor |
Secondary Temperature sensor | SBE 3P | 3P-4593 | 01/08/2012 | Secondary sensor |
Dissolved oxygen | SBE 43 | 43-1624 | 03/03/2012 | - |
Fluorometer | Chelsea MKIII Aquatracka fluorometer | 88-2615-126 | 04/05/2012 | - |
Transmissometer | Chelsea MKII 25cm path Alphatracka transmissometer | 161047 | 18/03/2008 | - |
Photosynthetically Active Radiation | CTG 2pi PAR irradiance sensor, DWIRR | PAR 03 | 14/06/2011 | All titanium casts shallower than 500 metres |
Altimeter | Tritech PA200 altimeter | 6196.118171 | 15/11/2006 | - |
Turbidity meter | WET Labs BBRTD light scatter sensor | BBRTD-169 | 14/04/2010 | - |
Sea-Bird Electronics SBE 911 and SBE 917 series CTD profilers
The SBE 911 and SBE 917 series of conductivity-temperature-depth (CTD) units are used to collect hydrographic profiles, including temperature, conductivity and pressure as standard. Each profiler consists of an underwater unit and deck unit or SEARAM. Auxiliary sensors, such as fluorometers, dissolved oxygen sensors and transmissometers, and carousel water samplers are commonly added to the underwater unit.
Underwater unit
The CTD underwater unit (SBE 9 or SBE 9 plus) comprises a protective cage (usually with a carousel water sampler), including a main pressure housing containing power supplies, acquisition electronics, telemetry circuitry, and a suite of modular sensors. The original SBE 9 incorporated Sea-Bird's standard modular SBE 3 temperature sensor and SBE 4 conductivity sensor, and a Paroscientific Digiquartz pressure sensor. The conductivity cell was connected to a pump-fed plastic tubing circuit that could include auxiliary sensors. Each SBE 9 unit was custom built to individual specification. The SBE 9 was replaced in 1997 by an off-the-shelf version, termed the SBE 9 plus, that incorporated the SBE 3 plus (or SBE 3P) temperature sensor, SBE 4C conductivity sensor and a Paroscientific Digiquartz pressure sensor. Sensors could be connected to a pump-fed plastic tubing circuit or stand-alone.
Temperature, conductivity and pressure sensors
The conductivity, temperature, and pressure sensors supplied with Sea-Bird CTD systems have outputs in the form of variable frequencies, which are measured using high-speed parallel counters. The resulting count totals are converted to numeric representations of the original frequencies, which bear a direct relationship to temperature, conductivity or pressure. Sampling frequencies for these sensors are typically set at 24 Hz.
The temperature sensing element is a glass-coated thermistor bead, pressure-protected inside a stainless steel tube, while the conductivity sensing element is a cylindrical, flow-through, borosilicate glass cell with three internal platinum electrodes. Thermistor resistance or conductivity cell resistance, respectively, is the controlling element in an optimized Wien Bridge oscillator circuit, which produces a frequency output that can be converted to a temperature or conductivity reading. These sensors are available with depth ratings of 6800 m (aluminium housing) or 10500 m (titanium housing). The Paroscientific Digiquartz pressure sensor comprises a quartz crystal resonator that responds to pressure-induced stress, and temperature is measured for thermal compensation of the calculated pressure.
Additional sensors
Optional sensors for dissolved oxygen, pH, light transmission, fluorescence and others do not require the very high levels of resolution needed in the primary CTD channels, nor do these sensors generally offer variable frequency outputs. Accordingly, signals from the auxiliary sensors are acquired using a conventional voltage-input multiplexed A/D converter (optional). Some Sea-Bird CTDs use a strain gauge pressure sensor (Senso-Metrics) in which case their pressure output data is in the same form as that from the auxiliary sensors as described above.
Deck unit or SEARAM
Each underwater unit is connected to a power supply and data logging system: the SBE 11 (or SBE 11 plus) deck unit allows real-time interfacing between the deck and the underwater unit via a conductive wire, while the submersible SBE 17 (or SBE 17 plus) SEARAM plugs directly into the underwater unit and data are downloaded on recovery of the CTD. The combination of SBE 9 and SBE 17 or SBE 11 are termed SBE 917 or SBE 911, respectively, while the combinations of SBE 9 plus and SBE 17 plus or SBE 11 plus are termed SBE 917 plus or SBE 911 plus.
Specifications
Specifications for the SBE 9 plus underwater unit are listed below:
Parameter | Range | Initial accuracy | Resolution at 24 Hz | Response time |
---|---|---|---|---|
Temperature | -5 to 35°C | 0.001°C | 0.0002°C | 0.065 sec |
Conductivity | 0 to 7 S m-1 | 0.0003 S m-1 | 0.00004 S m-1 | 0.065 sec (pumped) |
Pressure | 0 to full scale (1400, 2000, 4200, 6800 or 10500 m) | 0.015% of full scale | 0.001% of full scale | 0.015 sec |
Further details can be found in the manufacturer's specification sheet.
Chelsea Technologies Group Aquatracka MKIII fluorometer
The Chelsea Technologies Group Aquatracka MKIII is a logarithmic response fluorometer. Filters are available to enable the instrument to measure chlorophyll, rhodamine, fluorescein and turbidity.
It uses a pulsed (5.5 Hz) xenon light source discharging along two signal paths to eliminate variations in the flashlamp intensity. The reference path measures the intensity of the light source whilst the signal path measures the intensity of the light emitted from the specimen under test. The reference signal and the emitted light signals are then applied to a ratiometric circuit. In this circuit, the ratio of returned signal to reference signal is computed and scaled logarithmically to achieve a wide dynamic range. The logarithmic conversion accuracy is maintained at better than one percent of the reading over the full output range of the instrument.
Two variants of the instrument are available, both manufactured in titanium, capable of operating in depths from shallow water down to 2000 m and 6000 m respectively. The optical characteristics of the instrument in its different detection modes are visible below:
Excitation | Chlorophyll a | Rhodamine | Fluorescein | Turbidity |
---|---|---|---|---|
Wavelength (nm) | 430 | 500 | 485 | 440* |
Bandwidth (nm) | 105 | 70 | 22 | 80* |
Emission | Chlorophyll a | Rhodamine | Fluorescein | Turbidity |
Wavelength (nm) | 685 | 590 | 530 | 440* |
Bandwidth (nm) | 30 | 45 | 30 | 80* |
* The wavelengths for the turbidity filters are customer selectable but must be in the range 400 to 700 nm. The same wavelength is used in the excitation path and the emission path.
The instrument measures chlorophyll a, rhodamine and fluorescein with a concentration range of 0.01 µg l-1 to 100 µg l-1. The concentration range for turbidity is 0.01 to 100 FTU (other wavelengths are available on request).
The instrument accuracy is ± 0.02 µg l-1 (or ± 3% of the reading, whichever is greater) for chlorophyll a, rhodamine and fluorescein. The accuracy for turbidity, over a 0 - 10 FTU range, is ± 0.02 FTU (or ± 3% of the reading, whichever is greater).
Further details are available from the Aquatracka MKIII specification sheet.
Biospherical Instruments Log Quantum Cosine Irradiance Sensor QCP-2300 & QCP-2350
The QCP-2300 is a submersible cosine-collector radiometer designed to measure irradiance over Photosynthetically Active Radiation (PAR) wavelengths. It features a constant (better than ±10%) quantum response from 400 to 700 nm with the response being sharply attenuated above 700 nm and below 400 nm.
The sensor is a blue-enhanced high stability silicon photovoltaic detector with dielectric and absorbing glass filter assembly. The output is a DC voltage typically between 0 and 5 VDC that is proportional to the log of the incident irradiance.
The QCP-2300 is specifically designed for integration with 12-bit CTD systems and dataloggers requiring a limited-range of signal input.
Specifications
Wavelength | 400 to 700 nm |
PAR Spectral Response | better than ± 10% over 400-700 nm |
Cosine Directional Response | ± 5% 0 to 65°; ± 10% 0 to 85° |
Noise level | < 1 mV |
Temperature Range | -2 to 35 °C |
Depth Range (standard) | 1000 m |
Further details can be found in the manufacturer's manual.
.Paroscientific Absolute Pressure Transducers Series 3000 and 4000
Paroscientific Series 3000 and 4000 pressure transducers use a Digiquartz pressure sensor to provide high accuracy and precision data. The sensor comprises a quartz crystal resonator that responds to pressure-induced stress, and temperature is measured for thermal compensation of the calculated pressure.
The 3000 series of transducers includes one model, the 31K-101, whereas the 4000 series includes several models, listed in the table below. All transducers exhibit repeatability of better than ±0.01% full pressure scale, hysteresis of better than ±0.02% full scale and acceleration sensitivity of ±0.008% full scale /g (three axis average). Pressure resolution is better than 0.0001% and accuracy is typically 0.01% over a broad range of temperatures.
Differences between the models lie in their pressure and operating temperature ranges, as detailed below:
Model | Max. pressure (psia) | Max. pressure (MPa) | Temperature range (°C) |
---|---|---|---|
31K-101 | 1000 | 6.9 | -54 to 107 |
42K-101 | 2000 | 13.8 | 0 to 125 |
43K-101 | 3000 | 20.7 | 0 to 125 |
46K-101 | 6000 | 41.4 | 0 to 125 |
410K-101 | 10000 | 68.9 | 0 to 125 |
415K-101 | 15000 | 103 | 0 to 50 |
420K-101 | 20000 | 138 | 0 to 50 |
430K-101 | 30000 | 207 | 0 to 50 |
440K-101 | 40000 | 276 | 0 to 50 |
Further details can be found in the manufacturer's specification sheet.
WETLabs C-Star transmissometer
This instrument is designed to measure beam transmittance by submersion or with an optional flow tube for pumped applications. It can be used in profiles, moorings or as part of an underway system.
Two models are available, a 25 cm pathlength, which can be built in aluminum or co-polymer, and a 10 cm pathlength with a plastic housing. Both have an analog output, but a digital model is also available.
This instrument has been updated to provide a high resolution RS232 data output, while maintaining the same design and characteristics.
Specifications
Pathlength | 10 or 25 cm |
Wavelength | 370, 470, 530 or 660 nm |
Bandwidth | ~ 20 nm for wavelengths of 470, 530 and 660 nm ~ 10 to 12 nm for a wavelength of 370 nm |
Temperature error | 0.02 % full scale °C-1 |
Temperature range | 0 to 30°C |
Rated depth | 600 m (plastic housing) 6000 m (aluminum housing) |
Further details are available in the manufacturer's specification sheet or user guide.
UK Ocean Acidification (UKOA) cruise JR20130109 CTD processing
Sampling strategy
A total of 78 successful CTD casts were made during the cruise using both a titanium and stainless steel frame. Three data files for each cast were supplied to BODC, one for the downcast, upcast and one from the combined down and upcast. One exception was cast 42 of the titanium rosette, where no upcast was recorded. Rosette bottles were fired throughout the water column on the upcast of most profiles. Data were measured by a PC running Seasave V 7.21d, Sea-Bird's data acquisition software. The raw data files were supplied to BODC after the cruise.
Originator's processing
The initial Sea-Bird processing of the CTD profiles was carried out by the data originators at NOCL.
Sea-Bird processing
The raw data files have the appendices: .hex, .HDR, .bl and .CON. The .CON files for each cast contain the calibration coefficients for the instrument. The .HDR files contain the header information for each data file. The .hex files are the data files for each cast and are in hex format. The .bl files contain CTD scans that were collected while the water bottles were being closed.
A few issues were identified with the data during Sea-Bird processing. Soaks were missing from casts 09s, 10s, 28s, 47s and 76s of the stainless steel rosette and casts 05t, 06t, 07t, 08t, 48t, 50t, 57t and 77t of the titanium rosette. In some cases, due to the missing soaks, a large amount of surface data had to be removed. Also, in cast 72t, there was a spike in the pressure channel at about 4058 seconds that was not removed during WILDEDIT processing. This led to null data in most of the other channels, all of which were flagged as null.
Data were processed following established BODC procedures and the following SeaBird routines were carried out: DATCNV, BOTTLESUM, WILDEDIT, FILTER, ALIGNCTD, CELLTM, LOOPEDIT, DERIVE and BINAVERAGE. In the first instance, each raw CTD file was converted to ASCII format using the latest available version of the SeaBird Processing software, SBE Data Conversion (DATCNV). Further details of the BODC routines applied follow.
- DATCNV was run on all raw files. For the conversion of oxygen concentration, a window size of 2 was used, and tau and hysteresis corrections were applied.
- WILDEDIT was run to remove spikes in the pressure and depth channels of each cast. Flags were applied where values differed from the mean by more than two standard deviations on the first pass, or more than 20 standard deviations on the second pass, using 100 scans per block. The conductivity channel contained large spikes in many of the casts in both the primary and secondary channels. These spikes were removed by hand and replaced with the mean of the adjacent conductivity values. When a large number of data had to be removed, the conductivity values were flagged rather than replaced with a mean value.
- ALIGNCTD was run on the temperature and conductivity channels from both CTD's to ensure data were obtained from the same body of water, for any later derivations. Three randomly selected casts from each CTD were used to identify whether any sudden changes in one channel were aligned to any other channel. This process was also carried out on the secondary temperature and conductivity channels. No correction was required for either the primary or secondary temperature channel of the stainless steel CTD or of the titanium CTD, as the changes in conductivity were well aligned with those in temperature. To ensure the oxygen concentration corresponded to the correct pressure, the alignment of the oxygen channel was checked for both CTDs. For the stainless steel CTD, the differences between the up and downcast were least when the oxygen channel was adjusted by 4.0 seconds. Using SBE Align, a correction of four seconds was applied to the oxygen channel of each stainless steel CTD cast. For casts 19 and 40 of the titanium CTD, the difference between the up and downcast was least when the oxygen channel was adjusted by 3.8 seconds. Using SBE Align, a correction of 3.8 seconds was applied to the oxygen channel of each titanium CTD cast.
- CELLTM was used to remove conductivity cell thermal mass effects from the primary and secondary conductivity channels. The values used for the thermal anomaly amplitude and thermal anomaly constant were 0.03 and 7 respectively.
- DERIVE was used to obtain depth, nitrogen saturation, oxygen concentration, primary and secondary practical salinity, primary and secondary density and the primary and secondary sigma t values. For the derivation of oxygen, a window size of 2 was used and tau and hysteresis corrections were applied.
- BINAVERAGE was used to separate the data into 1 m bins. For each cast, the surface bin minimum value used was 1 m. The exceptions were casts: 3t (14m used for the downcast), 16s (4m used for the downcast), 46s (5m used for both the down- and the upcast), 51s (5m used for the downcast) and 52s (6m used for the downcast). These minimum surface bin values were used instead due to unreliable data for the derived variables being observed below 1m.
- STRIP was used to remove the surplus oxygen, depth and nitrogen saturation channels.
Field calibrations
Calibration of the oxygen sensor
Oxygen data were calibrated against discrete sample data. There was no significant drift in the stainless steel CTD oxygen sensor, only an offset. Ignoring the upper and lower 10% of the error, a mean offset of 0.293 was calculated and used to correct the oxygen channel on the stainless steel CTD. Due to ambiguity in the station and bottle numbers recorded for the titanium CTD, it was not possible to calibrate the oxygen channel for the titanium casts.
Salinity calibration
There was a consistent drift in the salinity channel of the stainless steel CTD so a correction was applied to both the primary and secondary salinity channels. To calculate the drift and offset in the data, a first order polynomial regression was used. To prevent any anomalous values affecting the corrections, the regression was only used once the lower and upper 10% of the error had been disregarded since the increase in the error was reasonably constant between these points. Where day is the number of days since the first cast, the corrected primary salinity was calculated as follows.
- Corrected Salinity = Salinity + 1.44 * 10-4 * Day + 0.0118
The corrected secondary salinity was calculated as follows.
- Corrected salinity = salinity + 1.894 * 10-4 * Day + 0.00939.
There was also a consistent drift in the salinity channel of the titanium CTD so a correction was applied to both the primary and secondary salinity channels. A first order polynomial regression was used again, ignoring the upper and lower 10% of errors. The corrected primary salinity was calculated as follows.
- Corrected Salinity = Salinity + 4.090 * 10-5 * Day + 0.00160
The corrected secondary salinity was calculated as follows.
- Corrected Salinity = Salinity - 2.768 * 10-5 * Day + 8.713 * 10-4.
BODC Reformatting
The data were converted from Sea-Bird ASCII format into BODC internal format using BODC transfer function 357. The following tables show how the variables within the Sea-Bird files were mapped to appropriate BODC parameter codes. Oxygen saturation, sigma-theta and potential temperature were derived and added to the profiles during the transfer.
For the stainless steel casts
Originator's Parameter Name | Units | Description | BODC Parameter Code | Units | Comments |
---|---|---|---|---|---|
prDM: Pressure, Digiquartz | dbar | Pressure (spatial co-ordinate) exerted by the water body by profiling pressure sensor and corrected to read zero at sea level | PRESPR01 | Decibars | - |
t090C: Temperature [ITS-90] | °C | Temperature of the water body by CTD or STD | TEMPST01 | Degrees Celsius | Dropped after transfer |
t190C: Temperature, 2 [ITS-90] | °C | Temperature of the water body by CTD or STD | TEMPST02 | Degrees Celsius | - |
c0S/m: Conductivity | S/m | Electrical conductivity of the water body by CTD | CNDCST01 | Siemens per metre | Dropped after transfer |
c1S/m: Conductivity, 2 | S/m | Electrical conductivity of the water body by CTD | CNDCST02 | Siemens per metre | Dropped after transfer |
sbeox0V: Oxygen raw, SBE 43 (v0: Voltage 0) | volts | Instrument output (voltage) by in-situ oxygen microelectrode | OXYVLTN1 | volts | Dropped after transfer |
flC: Fluorescence, Chelsea Aqua 3 Chl Con | ug/l | Concentration of chlorophyll-a {chl-a} per unit volume of the water body [particulate phase] by in-situ chlorophyll fluorometer and manufacturer's calibration applied | CPHLPM01 | Milligrams per cubic metre | - |
par: PAR/Irradiance, Biospherical/Licor | µE/m2/s | Downwelling vector irradiance as photons (PAR wavelengths) in the water body by cosine-collector radiometer | IRRDUV01 | MicroEinsteins per square metre per second | - |
CStarAt0: Beam Attenuation, WET Labs C-Star | 1/m | Attenuance (red light wavelength) per unit length of the water body by 25cm path length red light transmissometer | ATTNDR01 | per metre | - |
sbeox0ML/L: Oxygen, SBE 43, voltage 0 | ml/l | Concentration of oxygen {O2} per unit volume of the water body [dissolved phase] by Sea-Bird SBE 43 sensor and calibration against sample data | DOXYSC01 | Micromoles per litre | Converted from ml/l to micromoles/l during transfer |
sal00: Salinity, Practical [PSU] | PSU | Practical salinity of the water body by CTD and computation using UNESCO 1983 algorithm | PSALST01 | Dimensionless | Dropped after transfer |
sal11: Salinity, Practical, 2 [PSU] | PSU | Practical salinity of the water body by CTD and computation using UNESCO 1983 algorithm | PSALST02 | Dimensionless | - |
v0: Voltage 0 | volts | WETLabs C-Star transmissometer voltage | TVLTDR01 | V | Dropped after transfer |
v2: Voltage 2 | volts | Chelsea MKIII Aquatracka fluorometer voltage | FVLTAQ01 | V | Dropped after transfer |
v3: Voltage 3 | volts | PAR/Irradiance, Biospherical/Licor voltage | LVLTBD01 | V | Dropped after transfer |
v4: Voltage 4 | volts | Altimeter voltage | - | - | Channel not transferred |
v5: Voltage 5 | volts | Oxygen voltage | - | - | Channel not transferred |
v6: Voltage 6 | - | - | - | - | No sensor for voltage 6 |
v7: Voltage 7 | - | - | - | - | No sensor for voltage 7 |
Oxygen Saturation [%] - (Garcia and Gordon) | % | - | - | - | Channel not transferred. |
depSM: Depth [salt water] | m | - | - | - | Channel not transferred. |
n2satML/L: Nitrogen Saturation | ml/l | - | - | - | Channel not transferred. |
density00: Density [density, | Kg/m3 | - | - | - | Channel not transferred. |
sigma-t00: Density [sigma-t] | Kg/m3 | - | - | - | Channel not transferred. |
density11: Density, 2 [density] | Kg/m3 | - | - | - | Channel not transferred. |
sigma-t11: Density, 2 [sigma-t] | Kg/m3 | - | - | - | Channel not transferred. |
timeS: Time, Elapsed | seconds | - | - | - | Channel not transferred. |
svCM: Sound Velocity [Chen-Millero] | m/s | - | - | - | Channel not transferred. |
svCM1: Sound Velocity, 2 [Chen-Millero] | m/s | - | - | - | Channel not transferred. |
- | - | Oxygen saturation | OXYSSC01 | % | Generated by BODC using the Benson and Krause (1984) algorithm with parameters DOXYSC01, PSALST01 and TEMPST01. |
- | - | Sigma-theta | SIGTPR01 | kg/m3 | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. Dropped after transfer |
- | - | Potential temperature | POTMCV01 | °C | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. Dropped after transfer |
- | - | Sigma-theta, secondary | SIGTPR02 | kg m-3 | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
- | - | Potential temperature, secondary | POTMCV02 | °C | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
For the titanium casts
Originator's Parameter Name | Units | Description | BODC Parameter Code | Units | Comments |
---|---|---|---|---|---|
prDM: Pressure, Digiquartz | dbar | Pressure (spatial co-ordinate) exerted by the water body by profiling pressure sensor and corrected to read zero at sea level | PRESPR01 | Decibars | - |
t090C: Temperature [ITS-90] | °C | Temperature of the water body by CTD or STD | TEMPST01 | Degrees Celsius | Dropped after transfer |
t190C: Temperature, 2 [ITS-90] | °C | Temperature of the water body by CTD or STD | TEMPST02 | Degrees Celsius | - |
c0S/m: Conductivity | S/m | Electrical conductivity of the water body by CTD | CNDCST01 | Siemens per metre | Dropped after transfer |
c1S/m: Conductivity, 2 | S/m | Electrical conductivity of the water body by CTD | CNDCST02 | Siemens per metre | Dropped after transfer |
sbeox0V: Oxygen raw, SBE 43 (v0: Voltage 0) | volts | Instrument output (voltage) by in-situ oxygen microelectrode | OXYVLTN1 | volts | Dropped after transfer |
flC: Fluorescence, Chelsea Aqua 3 Chl Con | ug/l | Concentration of chlorophyll-a {chl-a} per unit volume of the water body [particulate phase] by in-situ chlorophyll fluorometer and manufacturer's calibration applied | CPHLPM01 | Milligrams per cubic metre | - |
par: PAR/Irradiance, Biospherical/Licor | W m-2 | Downwelling 2-pi scalar irradiance as energy (PAR wavelengths) in the water body by 2-pi scalar radiometer | DWIRPP01 | Watts per square metre | - |
sbeox0ML/L: Oxygen, SBE 43 | ml/l | Concentration of oxygen {O2} per unit volume of the water body [dissolved phase] by Sea-Bird SBE 43 sensor and no calibration against sample data | DOXYSU01 | Micromoles per litre | Converted from ml/l to micromoles/l during transfer |
sal00: Salinity, Practical [PSU] | PSU | Practical salinity of the water body by CTD and computation using UNESCO 1983 algorithm | PSALST01 | Dimensionless | Dropped after transfer |
sal11: Salinity, Practical, 2 [PSU] | PSU | Practical salinity of the water body by CTD and computation using UNESCO 1983 algorithm | PSALST02 | Dimensionless | - |
v0: Voltage 0 | volts | Oxygen voltage | - | - | Channel not transferred |
v1: Voltage 1 | volts | - | - | - | No sensor for voltage 1 |
v2: Voltage 2 | volts | CTG 2pi PAR irradiance sensor, DWIRR voltage | LVLTPU01 | V | Dropped after transfer |
v3: Voltage 3 | volts | - | - | - | No sensor for voltage 3 |
v4: Voltage 4 | volts | Chelsea MKII 25cm path Alphatracka transmissometer voltage | TVLTDR01 | V | Dropped after transfer |
v5: Voltage 5 | volts | Chelsea MKIII Aquatracka fluorometer voltage | FVLTAQ01 | V | Dropped after transfer |
v6: Voltage 6 | volts | Turbidity Meter, WET Labs, ECO-BB voltage | NVLTWR01 | V | Dropped after transfer |
v7: Voltage 7 | volts | Tritech PA200 Altimeter voltage | - | - | Channel not transferred |
depSM: Depth [salt water] | m | - | - | - | Channel not transferred. |
n2satML/L: Nitrogen Saturation | ml/l | - | - | - | Channel not transferred. |
density00: Density [density, | Kg/m3 | - | - | - | Channel not transferred. |
sigma-t00: Density [sigma-t] | Kg/m3 | - | - | - | Channel not transferred. |
density11: Density, 2 [density] | Kg/m3 | - | - | - | Channel not transferred. |
sigma-t11: Density, 2 [sigma-t] | Kg/m3 | - | - | - | Channel not transferred. |
timeS: Time, ElapseD | seconds | - | - | - | Channel not transferred. |
svCM1: Sound Velocity, 2 [Chen-Millero] | m/s | - | - | - | Channel not transferred. |
- | - | Oxygen saturation | OXYSSU01 | % | Generated by BODC using the Benson and Krause (1984) algorithm with parameters DOXYSU01, PSALST01 and TEMPST01. |
- | - | Sigma-theta | SIGTPR01 | kg m-3 | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
- | - | Potential temperature | POTMCV01 | °C | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
- | - | Sigma-theta, secondary | SIGTPR02 | kg m-3 | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
- | - | Potential temperature, secondary | POTMCV02 | °C | Generated by BODC using the Fofonoff and Millard (1982) algorithm from frame mounted sensors. |
Screening
Reformatted CTD data were visualised using the in-house graphical editor EDSERPLO. No data values were edited or deleted, and all spurious and null data were flagged with BODC quality control flags.
Titanium cast PAR
Comparison between the voltage values and PAR values provided in the files with the calibration certificates showed that the data were by a factor of 0.04234 for the PAR values derived from voltages. This is a recurring problem with the way coefficients are entered into the Sea-Bird .CON files onboard the ship. A correction factor of /0.04234 was applied to the DWIRPP01 channel.
Banking
Once quality control screening was complete, the CTD downcasts were banked.
References
Benson, B.B., and Krausse Jr, D., 1984. The concentration and isotopic fractionation of oxygen dissolved in freshwater and seawater in equilibrium with the atmosphere. The American Society of Limnology and Oceanography, 29 (3), p.620 - 637.
Fofonoff, N.P., and Millard, R.C., 1983. Algorithms for computations of fundamental properties of seawater. UNESCO Technical Papers in Marine Science, 44, p. 53.
UNESCO, 1981. Background papers and supporting data on the International Equation of State of Seawater 1980. UNESCO Technical Papers in Marine Science, 38, p. 192.
Project Information
UKOARP Theme B: Ocean acidification impacts on sea surface biology, biogeochemistry and climate
The overall aim of this theme is to obtain a quantitative understanding of the impact of ocean acidification (OA) on the surface ocean biology and ecosystem and on the role of the surface ocean within the overall Earth System.
The aims of the theme are:
- To ascertain the impact of OA on planktonic organisms (in terms of physiological impacts, morphology, population abundances and community composition).
- To quantify the impacts of OA on biogeochemical processes affecting the ocean carbon cycle (both directly and indirectly, such as via availability of bio-limiting nutrients).
- To quantify the impacts of OA on the air-sea flux of climate active gases (DMS and N2O in particular).
The main consortium activities will consist of in-situ measurements on three dedicated cruises, as well as on-deck bioassay experiments probing the response of the in-situ community to elevated CO2. Most of the planned work will be carried out on the three cruises to locations with strong gradients in seawater carbon chemistry and pH; the Arctic Ocean, around the British Isles and the Southern Ocean.
Weblink: http://www.oceanacidification.org.uk/research_programme/surface_ocean.aspx
Data Activity or Cruise Information
Cruise
Cruise Name | JR20130109 (JR274) |
Departure Date | 2013-01-09 |
Arrival Date | 2013-02-12 |
Principal Scientist(s) | Geraint Tarling (British Antarctic Survey) |
Ship | RRS James Clark Ross |
Complete Cruise Metadata Report is available here
Fixed Station Information
No Fixed Station Information held for the Series
BODC Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
---|---|
Blank | Unqualified |
< | Below detection limit |
> | In excess of quoted value |
A | Taxonomic flag for affinis (aff.) |
B | Beginning of CTD Down/Up Cast |
C | Taxonomic flag for confer (cf.) |
D | Thermometric depth |
E | End of CTD Down/Up Cast |
G | Non-taxonomic biological characteristic uncertainty |
H | Extrapolated value |
I | Taxonomic flag for single species (sp.) |
K | Improbable value - unknown quality control source |
L | Improbable value - originator's quality control |
M | Improbable value - BODC quality control |
N | Null value |
O | Improbable value - user quality control |
P | Trace/calm |
Q | Indeterminate |
R | Replacement value |
S | Estimated value |
T | Interpolated value |
U | Uncalibrated |
W | Control value |
X | Excessive difference |
SeaDataNet Quality Control Flags
The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:
Flag | Description |
---|---|
0 | no quality control |
1 | good value |
2 | probably good value |
3 | probably bad value |
4 | bad value |
5 | changed value |
6 | value below detection |
7 | value in excess |
8 | interpolated value |
9 | missing value |
A | value phenomenon uncertain |
B | nominal value |
Q | value below limit of quantification |