Dataset: GT10-11 - DIC_TA
Deployment: KN199-04

Inorganic Carbon data from GT10 and GT11 North Atlantic cruises

Principal Investigator:

Nicholas Bates (Bermuda Institute of Ocean Sciences, BIOS)

BCO-DMO Data Manager:

Danie Kinkade (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

U.S. GEOTRACES North Atlantic Transect (GA03) (U.S. GEOTRACES NAT)

Current State:

Preliminary and in progress

Version:

2012-12-31

Deployment Synonyms:

GA03, GT10, USGT-NAT-2010, KN199-4, GNAT, U.S. GEOTRACES NAZT Leg 1, knorr199-4/5, Section Cruise (GA03), 316N20101015

Version Date:

2012-12-31

Data URL:

https://www.bco-dmo.org/dataset-deployment/455681/data

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Description

Dissolved inorganic carbon (DIC) and total alkalinity (TA) data from the 2010 and 2011 GEOTRACES North Atlantic Cruises.

Methods & Sampling

Dataset acquisition description

Sampling and Analytical Methodology:
DIC and TA samples: Sampling from the Niskin followed standard CLIVAR-CO2, GEOTRACES and GO-ship protocols. Samples were collected in ~500 ml Pyrex bottles that were poisoned with 100 μl Hg2Cl, sealed and stored in the dark before analysis back in the laboratory at BIOS. DIC was determined using a high precision (0.05%CV) coulometer based instrument (VINDTA 3C)(Bates et al., 2012). TA was determined by a high- precision (<0.05%CV) potentiometric technique using a VINDTA 2S (Marianda, Germany). Replicate samples were also analyzed at BIOS. Both DIC and TA instruments were routinely calibrated using seawater Certified Reference Material (CRM) from A.G. Dickson, Scripps Institute of Oceanography, and the accuracy of samples compared to CRM’s was less than 0.1% (2 μmoles kg-1).

Data Processing Description

Dataset Processing Description

Data Processing:
DIC and TA data have been corrected to CRM values. Quality flags here include:

2: good data
5: questionable data
6: bad data (denoted in data column by -999)
9: no data

BCO-DMO Processing Notes:

Original file submission on 2012.12.21. Corrected file submitted on 2013.01.30.

Edits:
-Parameter names were modified to conform with BCO-DMO conventions.
-Completed metadata parameters for missing fields of duplicate bottles from station 20 bottles 4, 6, 8.
-Removed reference to cruise KN199-05 and cruise parts A and B for cruise KN204-01 in header comments.

Note: bad data values of -999, submitted by the PI, were retained in the data.

Additional GEOTRACES Processing: After the data were submitted to the International Data Management Office, BODC, the office noticed that important identifying information was missing in many datasets. With the agreement of BODC and the US GEOTRACES lead PIs, BCO-DMO added standard US GEOTRACES information, such as the US GEOTRACES event number, to each submitted dataset lacking this information. To accomplish this, BCO-DMO compiled a 'master' dataset composed of the following parameters: station_GEOTRC, cast_GEOTRC (bottle and pump data only), event_GEOTRC, sample_GEOTRC, sample_bottle_GEOTRC (bottle data only), bottle_GEOTRC (bottle data only), depth_GEOTRC_CTD (bottle data only), depth_GEOTRC_CTD_rounded (bottle data only), BTL_ISO_DateTime_UTC (bottle data only), and GeoFish_id (GeoFish data only). This added information will facilitate subsequent analysis and inter comparison of the datasets.

Bottle parameters in the master file were taken from the GT-C_Bottle_GT10, GT-C_Bottle_GT11, ODF_Bottle_GT10, and ODF_Bottle_GT11 datasets. Non-bottle parameters, including those from GeoFish tows, Aerosol sampling, and McLane Pumps, were taken from the Event_Log_GT10 and Event_Log_GT11 datasets. McLane pump cast numbers missing in event logs were taken from the Particulate Th-234 dataset submitted by Ken Buesseler.

A standardized BCO-DMO method (called “join”) was then used to merge the missing parameters to each US GEOTRACES dataset, most often by matching on sample_GEOTRC or on some unique combination of other parameters.

If the master parameters were included in the original data file and the values did not differ from the master file, the original data columns were retained and the name of the parameters were changed from the PI-submitted names to the standardized master names. If there were differences between the PI-supplied parameter values and those in the master file, both columns were retained. If the original data submission included all of the master parameters, no additional columns were added, but parameter names were modified to match the naming conventions of the master file.

See the dataset parameters documentation for a description of which parameters were supplied by the PI and which were added via the join method.

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-1132566	NSF Division of Ocean Sciences

Instruments

Automatic titrator

Supplied Description:

TA was determined by a high- precision (<0.05%CV) potentiometric technique using a VINDTA 2S (Marianda, Germany).

From MIRIANDA Co.:

The VINDTA (Versatile INstrument for the Determination of Titration Alkalinity) is a system for titration of a sample with acid and analysis of the titration curve to calculate alkalinity. The system was developed to meet the requirements in precision (better 0.1%) for open ocean CO₂ research. A full titration takes less than 20 minutes and requires about 250 ml sample volume (~ 150 ml minimum).

Instrument Type

Generic Name: Automatic titrator

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB12/

Generic Description:

Instruments that incrementally add quantified aliquots of a reagent to a sample until the end-point of a chemical reaction is reached.

MARIANDA VINDTA 3C total inorganic carbon and titration alkalinity analyser

Supplied Description:

DIC was determined using a high precision (0.05%CV) coulometer based instrument (VINDTA 3C)(Bates et al., 2012)

Instrument Type

Generic Name: MARIANDA VINDTA 3C total inorganic carbon and titration alkalinity analyser

Acronym: inorganic carbon and alkalinity analyser

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/TOOL0481/

Generic Description:

The Versatile INstrument for the Determination of Total inorganic carbon and titration Alkalinity (VINDTA) 3C is a laboratory alkalinity titration system combined with an extraction unit for coulometric titration, which simultaneously determines the alkalinity and dissolved inorganic carbon content of a sample. The sample transport is performed with peristaltic pumps and acid is added to the sample using a membrane pump. No pressurizing system is required and only one gas supply (nitrogen or dry and CO2-free air) is necessary. The system uses a Metrohm Titrino 719S, an ORION-Ross pH electrode and a Metrohm reference electrode. The burette, the pipette and the analysis cell have a water jacket around them. Precision is typically +/- 1 umol/kg for TA and/or DIC in open ocean water.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
event_GEOTRC	Unique identifying number for US GEOTRACES sampling events; ranges from 2001 to 2225 for KN199-04 events and from 3001 to 3282 for KN204-01 events. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'GEOTRC_EVENTNO', this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	event
station_GEOTRC	GEOTRACES station number; ranges from 1 through 12 for KN199-04 and 1 through 24 for KN204-01. Stations 7 and 9 were skipped on KN204-01. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'STNNBR', this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	station
cast_GEOTRC	Cast identifier numbered consecutively within a station. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'CASTNO'; this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	cast
lat	Latitude component of geographic position where samples were collected.	decimal degrees	lat
lon	Longitude component of geographic position where samples were collected.	decimal degrees	lon
date_utc	Date in UTC. in the format yyyymmdd	unitless	date_utc
depth_bottom	Bottom depth in meters, reported as BTMDEPTH.	meters	depth_bottom
temp	Water temperature at sample depth, reported as CTDTMP.	degrees Celsius	temp
sal	CTD Salinity reported as CTDSAL.	dimensionless	sal
DIC	Dissolved inorganic Carbon.	micromoles/kg	DIC
DIC_qflag	Quality flag associated with DIC determination. See metadata for flag definitions.	dimensionless	q_flag
comments_DIC	Comments associated with DIC determination; originally reported as 'Comments', where NC = No Comment.	dimensionless	comment
TALK	Total Alkalinity of water sample; originally reported as TA.	micromoles per Kilogram	TALK
TALK_qflag	Quality flag associated with total alkalinity determination. See metadata for flag definitions.	dimensionless	q_flag
comments_TALK	Comments associated with total TALK determination; originally reported as 'Comments', where NC = No Comment.	dimensionless	comment
bottle_qflag	Quality flag associated with each bottle, reported as BTLNBR_FLAT_W.	dimensionless	q_flag
sal_bottle	Bottle salinity measurement, reported as SALNTY.	dimensionless	sal_bottle
sal_qflag	Quality flag associated with the CTD salinity measurement.	dimensionless	q_flag
sal_bottle_qflag	Quality flag associated with bottle salinity measurement.	dimensionless	q_flag
expocode	Expedition code is a unique cruise identifier code, required for every cruise dealt with by the CLIVAR and Carbon Hydrographic Data Office (CCHDO), of the format NODCshipcodeYearMonthDay.	dimensionless	no_bcodmo_term
sect_id	A unique alphanumeric code identifying cruise.	dimensionless	cruise_id
press	Water pressure at measurement, reported as CTDPRS.	decibars	press
time_utc	Time recorded in UTC.	hhmm	time_utc
sample_GEOTRC	Unique identifying number for US GEOTRACES samples; ranges from 5033 to 6078 for KN199-04 and from 6112 to 8148 for KN204-01. PI-supplied values were identical to those in the intermediate US GEOTRACES master file Originally submitted as 'GEOTRC_SAMPNO'; this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	sample
sample_bottle_GEOTRC	Unique identification numbers given to samples taken from bottles; rangies from 1 to 24; often used synonymously with bottle number. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'sample'; this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	sample
bottle_GEOTRC	Alphanumeric characters identifying bottle type (e.g. NIS representing Niskin and GF representing GOFLO) and position on a CTD rosette. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'BTLNBR'; this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	dimensionless	bottle
depth_GEOTRC_CTD	Observation/sample depth in meters; calculated from CTD pressure. PI-supplied values were identical to those in the intermediate US GEOTRACES master file. Originally submitted as 'CTDDEPTH'; this parameter name has been changed to conform to BCO-DMO's GEOTRACES naming conventions.	meters	depth
BTL_ISO_DateTime_UTC	Date and time (UTC) variable recorded at the bottle sampling time in ISO compliant format. Values were added from the intermediate US GEOTRACES master file (see Processing Description). This standard is based on ISO 8601:2004(E) and takes on the following form: 2009-08-30T14:05:00[.xx]Z (UTC time)	YYYY-MM-DDTHH:MM:SS[.xx][+/-TZ]	ISO_DateTime_UTC

Database

Contribute Data

Dataset: GT10-11 - DIC_TA
Deployment: KN199-04

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: GT10-11 - DIC_TADeployment: KN199-04

Dataset acquisition description

Dataset Processing Description

Dataset: GT10-11 - DIC_TA
Deployment: KN199-04