Dataset: Low-pH springs: water samples

Name: Measured and calculated geochemistry values and uncertainty for water samples taken from the water column of Celestun Lagoon, Yucatan, Mexico in May of 2015
Published: 2024-10-25
Keywords: boron isotopes, groundwater, benthic foraminifera, coastal pH, oceans

Cite This Dataset

DOI:10.26008/1912/bco-dmo.941377.1

Spatial Extent: N:20.95318 E:-90.32955 S:20.77012 W:-90.41782

Celestún Biosphere Reserve, Yucatan, Mexico. 20.88 N 90.36 E depth 0.5 m.

Temporal Extent: 2015-05-25 - 2015-05-26

Project:

Calcification in low saturation seawater: What can we learn from organisms in the proximity of low pH; undersaturated submarine springs (CalcificationLowSatSeawater)

Program:

Science, Engineering and Education for Sustainability NSF-Wide Investment (SEES): Ocean Acidification (formerly CRI-OA) (SEES-OA)

Principal Investigator:

Adina Paytan (University of California-Santa Cruz, UCSC)

Co-Principal Investigator:

Jorge A. Herrera-Silveira (Unidad Mérida del Centro de Investigación y de Estudios Avanzados, CINVESTAV)

Chen-Feng You (National Cheng Kung University)

Scientist:

Hou-Chun Arrien Liu (National Cheng Kung University)

Joseph H. Street (University of California-Santa Cruz, UCSC)

Tzu-Hao David Wang (National Cheng Kung University)

Student:

Kyle H. Hardage (University of California-Santa Cruz, UCSC)

Contact:

Adina Paytan (University of California-Santa Cruz, UCSC)

Data Manager:

Kyle H. Hardage (University of California-Santa Cruz, UCSC)

BCO-DMO Data Manager:

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

Version:

Version Date:

2024-10-25

Restricted:

Validated:

Yes

Current State:

Final no updates expected

Measured and calculated geochemistry values and uncertainty for water samples taken from the water column of Celestun Lagoon, Yucatan, Mexico in May of 2015

Abstract:

Measured and calculated geochemistry values and uncertainty for water samples taken from the water column of Celestun Lagoon, Yucatan, Mexico in May of 2015. This dataset was collected in coordination with the following study (See "Related Datasets" section): Isotopes (δ11B, 87Sr/86Sr, δ18O, δ13C), elemental concentrations (B, Mg, Ca), and carbon content were collected from the foraminifera Ammonia parkinsoniana and sediments in Celestun Lagoon, Yucatan, Mexico in June 2009 and May 2015. Sediment cores were taken with push corers and piston corers. Sampling site were distributed unevenly along a transect along the lagoon. These data were collected to investigate the influence of low-pH groundwater-seawater mixing on the boron isotope pH proxy.

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Archival Copy

Version Date	Archive	Persistent Identifier (PID)	Date PID Issued
2024-10-25	Marine Biological Laboratory/Woods Hole Oceanographic Institution Library (MBLWHOI DLA)	10.26008/1912/bco-dmo.941377.1	2024-12-18

Methods & Sampling

Location: Celestún Biosphere Reserve, Yucatan, Mexico. 20.88 N 90.36 E depth 0.5 m.
Collection: Data collected from dinghy. No vessel name. June 2009 and May 2015.

Water samples from 2015 were filtered (0.45 um) and analyzed for salinity, pH, and elemental concentrations. Analytical methods involved MC-ICPMS for boron and strontium isotopes, with careful sample preparation, including microsublimation for δ11B, Sr-spec resin for 87Sr/86Sr, and isotope ratio mass spectrometry for δ18O and δ13C. Elemental concentrations (B, Mg, Ca) were analyzed using ICPMS. Reproducibility was verified using established standards.

Additional methods citations:

Boron isotope method: Wang et al. (2020).
Strontium isotope method: Liu et al. (2012).
pH and borate equations: Foster et al. (2016).

Related dataset descriptions (See section "Related Datasets" for data citations):

The water sample data in this dataset were collected concurrently with the May 2015 sampling event in BCO-DMO dataset https://www.bco-dmo.org/dataset/941327 which contains isotope data, elemental concentrations, and carbon content collected from the foraminifera Ammonia parkinsoniana and sediments in Celestun Lagoon, Yucatan, Mexico in June 2009 and May 2015.

This study and Paytan (2021, BCO-DMO dataset https://www.bco-dmo.org/dataset/564766) both derive groundwater from the same regional aquifer in Yucatan, Mexico, and both studies review the effects of low-pH springs on saturation and calcification of organisms. They are different sample material.

The sediment cores and assemblages in Hardage et al. (2021, doi:10.25921/qkc1-yw35) at NOAA provide the sample material for the geochemistry reported in this study (foraminifera, bulk sediment, physical observations). The Hardage et al. (2021) dataset also contains additional lithology and geochemistry that can be paired with these new data for interested parties.

Instrument and equipment list:

LDPE bottles: water samples were collected in acid-washed LDPE bottles for trace metals.
rubber septum glass vials: water samples were collected in ashed glass bottles for nutrients.
0.5 mL micro-centrifuge tubes: used to store crushed foraminifera for cleaning.
Yellow Springs Instrument Model 63 handheld sonde and pH probe.
Neptune multi-collector inductively coupled plasma mass spectrometer (MC-ICPMS).
Lachat QuikChem 8000.
UIC Carbon Coulometer Analyzer (CM150).
Orion 950 Titrator.
Thermo Scientific Element XR ICPMS.
ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer.

Data Processing Description

Element data were corrected for blank, drift, mass bias, and calcium matrix effects.

Boron isotopes were corrected using the standard-sample-standard bracket technique to correct drift and bias across each individual sample.

pKB* and δ11B borate were calculated using Branson (2024) CBSYST with implementation of Hain et al. (2015) speciation of Ca and Mg.

The MarChemSpec (Clegg & Turner, 2023) model uses measured inputs of salinity, temperature, DIC, TA, [B], [Mg], [Ca], [NO₃^-], [PO₄^-], and [SiO₄^4-]. Other major ion concentrations were estimated by applying LOESS smoothing regression (R Software version 4.3.1) to salinity versus [Cl^-], [SO₄^2-], and [Sr²⁺] data from a lagoon transect in Young et al., (2008) to account for minor non-linear variations at lower salinity. [Na] and [K] concentrations were estimated from the LOESS-derived [Cl^-] using [X] = [Cl]_estimated/[Cl]_Millero * [X]_Millero, where [Cl]_Millero = 536 mM and X is typical seawater [Na] = 456 mM or [K] = 10.2 mM (Millero et al., 2008). These estimates apply for mixed lagoon waters only. For endmember waters (well water, seawater, large spring), values from were taken directly from Young et al. (2008) and assumed to reflect expected concentrations in the identical sampling locations in this study. Charge imbalances from MarChemSpec calculations were corrected by adjusting [Na], chosen because it was not measured and because its seawater concentration dominates charge balance adjustments relative to [K]. [Na] absolute adjustment ranged from about -22 to +19 mM (< 10 % of [Na]). MarChemSpec calculated pH on the total scale using Pitzer constants.

Software:

MarChemSpec software (https://marchemspec.org/wp/software/) has been archived at Zenodo (Clegg & Turner, 2023, doi: 10.5281/ZENODO.8373046).

CBSYST software (https://github.com/oscarbranson/cbsyst) Version 0.4.9 has been archived at Zenodo (Branson et al., 2024, doi: 10.5281/ZENODO.14185784).

See the "Parameters" section for more details applicable to each data column in this dataset including how MarChemSpec and CBSYST software was used.

Note about aggregated data (means, standard deviations):
The averages are from the instruments themselves, not from true replicates. They typically take 4 to 10 readings and average the result, depending on the instrument. Since these are mass spectrometers counting individual ions, this averaging is necessary to reduce noise. For parameters calculated using CBSYST, mean and standard deviation are derived from 10,000 Monte Carlo realizations.

BCO-DMO Processing

* Data table from submitted file "Hardage_boron_water_parameter_values.csv" (file supplied by email on 2024-12-06) was imported into the BCO-DMO data system for this dataset. Values "-999" imported as missing data values.
** In the BCO-DMO data system missing data identifiers are displayed according to the format of data you access. For example, in csv files it will be blank (null) values. In Matlab .mat files it will be NaN values. When viewing data online at BCO-DMO, the missing value will be shown as blank (null) values.

* Datetime with timezone (UTC) added as column from local dates and times provided in GMT-6 (Central Standard Time in Yucatan, Mexico).

* Table row order sorted by DateTime.

Data Files

File
941377_v1_water-samples.csv (Comma Separated Values (.csv), 6.71 KB) MD5:c35891b6af6afdb0bbaf4aa0754a91bb Primary data file for dataset ID 941377, version 1

More Information about this dataset

Funding Sources

Funding Source	Award Number
NSF Division of Ocean Sciences	OCE-1040952

Deployments

None available yet

Instruments

Automatic titrator

Supplied Name: Orion 950 Titrator

Supplied Description:

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.

Bottle

Supplied Name:

Supplied Description:

LDPE bottles: water samples were collected in acid-washed LDPE bottles for trace metals.
Rubber septum glass vials: water samples were collected in ashed glass bottles for nutrients.

Instrument Type

Generic Name: Bottle

Generic Description:

A container, typically made of glass or plastic and with a narrow neck, used for storing drinks or other liquids.

CM150 Total Carbon Analyzer

Supplied Name: UIC Carbon Coulometer Analyzer (CM150, UIC, Inc.)

Supplied Description:

Instrument housed at UCSC Marine Analytical Lab. CM150 (UIC, Inc.) Carbon Analysis (TC/TIC/TOC) By Combustion, Acidification And Coulometric Detection.

Instrument Type

Generic Name: CM150 Total Carbon Analyzer

Acronym: CM150

Generic Description:

The CM150 Total Carbon Analyzer, made by UIC, Inc., is a complete analytical system capable of measuring total carbon, total organic carbon and total inorganic carbon in solid and/or liquid samples. (From https://www.uicinc.com/cm150-carbon-analysis/).

Elemental Analyzer

Supplied Name: Carlo Erba elemental analyzer IRMS

Supplied Description:

Instrument Type

Generic Name: Elemental Analyzer

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB01/

Generic Description:

Instruments that quantify carbon, nitrogen and sometimes other elements by combusting the sample at very high temperature and assaying the resulting gaseous oxides. Usually used for samples including organic material.

Inductively Coupled Plasma Mass Spectrometer

Supplied Name: Thermo Scientific Element XR ICPMS

Supplied Description:

Instrument Type

Generic Name: Inductively Coupled Plasma Mass Spectrometer

Acronym: ICP Mass Spec

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB15/

Generic Description:

An ICP Mass Spec is an instrument that passes nebulized samples into an inductively-coupled gas plasma (8-10000 K) where they are atomized and ionized. Ions of specific mass-to-charge ratios are quantified in a quadrupole mass spectrometer.

Isotope-ratio Mass Spectrometer

Supplied Name: ThermoFinnigan Delta Plus XP isotope ratio mass spectrometer.

Supplied Description:

Instrument Type

Generic Name: Isotope-ratio Mass Spectrometer

Acronym: IR Mass Spec; IRMS

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/

Generic Description:

The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer).

Isotope-ratio Mass Spectrometer

Supplied Name:

Supplied Description:

Instrument Type

Generic Name: Isotope-ratio Mass Spectrometer

Acronym: IR Mass Spec; IRMS

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/

Generic Description:

The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer).

Isotope-ratio Mass Spectrometer

Supplied Name: ThermoScientific MAT-253 dual-inlet isotope ratio mass spectrometer

Supplied Description:

Instrument Type

Generic Name: Isotope-ratio Mass Spectrometer

Acronym: IR Mass Spec; IRMS

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/LAB16/

Generic Description:

The Isotope-ratio Mass Spectrometer is a particular type of mass spectrometer used to measure the relative abundance of isotopes in a given sample (e.g. VG Prism II Isotope Ratio Mass-Spectrometer).

Lachat QuikChem 8000 flow injection analyzer and Ion Chromatography (IC) system

Supplied Name: Lachat QuikChem 8000

Supplied Description:

Instrument Type

Generic Name: Lachat QuikChem 8000 flow injection analyzer and Ion Chromatography (IC) system

Generic Description:

The Lachat QuikChem 8000 can operate flow injection analysis and ion chromatography simultaneously and independently on the same instrument platform. Instrument includes sampler, dilutor, sampling pump, electronics unit, and data station. Analysis takes 20-60 seconds, with a sample throughput of 60-120 samples per hour. Measurements are in the range of parts per trillion to parts per hundred.

Multi Collector Inductively Coupled Plasma Mass Spectrometer

Supplied Name:

Supplied Description:

Neptune multi-collector inductively coupled plasma mass spectrometer (MC-ICPMS).

Instrument Type

Generic Name: Multi Collector Inductively Coupled Plasma Mass Spectrometer

Acronym: MC-ICPMS

Generic Description:

A Multi Collector Inductively Coupled Plasma Mass Spectrometry (MC-ICPMS) is a type of mass spectrometry where the sample is ionized in a plasma (a partially ionized gas, such as Argon, containing free electrons) that has been generated by electromagnetic induction. A series of collectors is used to detect several ion beams simultaneously.

A MC-ICPMS is a hybrid mass spectrometer that combines the advantages of an inductively coupled plasma source and the precise measurements of a magnetic sector multicollector mass spectrometer. The primary advantage of the MC-ICPMS is its ability to analyze a broader range of elements, including those with high ionization potential that are difficult to analyze by Thermal Ionization Mass Spectrometry (TIMS). The ICP source also allows flexibility in how samples are introduced to the mass spectrometer and allows the analysis of samples introduced either as an aspirated solution or as an aerosol produced by laser ablation.

Multi Parameter Portable Meter

Supplied Name: Yellow Springs Instrument Model 63 handheld sonde and pH probe

Supplied Description:

YSI Model 63 Handheld pH, Conductivity, Salinity and Temperature System.

Instrument Type

Generic Name: Multi Parameter Portable Meter

Generic Description:

An analytical instrument that can measure multiple parameters, such as pH, EC, TDS, DO and temperature with one device and is portable or hand-held.

Piston Corer

Supplied Name:

Supplied Description:

Piston, Bolivia, Livingstone corers: coring devices used to collect sediments.

Instrument Type

Generic Name: Piston Corer

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/51/

Generic Description:

The piston corer is a type of bottom sediment sampling device. A long, heavy tube is plunged into the seafloor to extract samples of mud sediment. A piston corer uses a "free fall" of the coring rig to achieve a greater initial force on impact than gravity coring. A sliding piston inside the core barrel reduces inside wall friction with the sediment and helps to evacuate displaced water from the top of the corer. A piston corer is capable of extracting core samples up to 90 feet in length.

Parameters

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

Supplied Name	Supplied description	Supplied Units	Standard Name
site	Site code for water sample.	unitless	site
lat	Site latitude in WGS84; north is positive.	decimal degrees	lat
long	Site longitude in WGS84; east is negative.	decimal degrees	lon
distance	Distance along the central lagoon axis from the northern fringe mangrove to the southern lagoon opening to the ocean.	kilometers (km)	length
region	Biogeographic region of the lagoon identified by Hardage et al. (2022). J. Paleolim. 10.8 km is the dividing point.	unitless	site_descrip
date	Date of sample collection in ISO 8601 yyyy-mm-dd format. Time Zone GMT-6 (Central Standard Time in Yucatan, Mexico) Format: %Y-%m-%d	unitless	date_local
time	Time of sample collection in ISO 8601 format HH:MM.	unitless	time_local
ISO_DateTime_UTC	DateTime with time zone of sample collection in ISO 8601 format (UTC). Format: %Y-%m-%dT%H:%MZ	unitless	no_bcodmo_term
tide	Tide position based on the nearest tide gauge in Progreso, Yucatan, Mexico.	unitless	tide
sample	Water sample type. Valid values are Lagoon Water, Seawater, Spring Water, Well Water.	unitless	sample_descrip
temperature	Water column temperature measured in situ.	degrees Celsius	temp
salinity	Water column salinity measured with a salinometer against KCl.	practical salinity units (PSU)	sal
pH	Water column pH, measured in situ using standards on the National Bureau of Standards scale and converted to total scale using pH = value - 0.14.	total scale	pH
DIC	Water column dissolved inorganic carbon.	micromoles per kilogram (umol/kg)	DIC
DIC_2sd	Water column dissolved inorganic carbon 2 standard deviations of replicate measurements.	micromoles per kilogram (umol/kg)	DIC
TA	Water column total alkalinity. Uncertainty determined as 45 based on the Dickson Standard Batch 121.	micromoles per kilogram (umol/kg)	TALK
NO3	Water column dissolved nitrate as N.	micromoles per kilogram (umol/kg)	NO3
NO3_2sd	Water column dissolved nitrate as N 2 standard deviations of replicate measurements.	micromoles per kilogram (umol/kg)	NO3
PO4	Water column dissolved phosphate. Uncertainty determined as +- 0.02 based on lab standards.	micromoles per kilogram (umol/kg)	PO4
SiO4	Water column dissolved silica.	micromoles per kilogram (umol/kg)	SiO4
SiO4_2sd	Water column dissolved silica 2 standard deviations of replicate measurements.	micromoles per kilogram (umol/kg)	SiO4
Ca_conc	Water column dissolved calcium concentration. Uncertainty determined as +- 0.2 from 2SD of lab standard gravimetric solutions.	millimolar (mM)	Ca
Mg_conc	Water column dissolved magnesium concentration. Uncertainty determined as +- 0.12 from 2SD of lab standard gravimetric solutions.	millimolar (mM)	Mg
B_conc	Water column dissolved boron concentration. Uncertainty determined as +- 31.6 from 2SD of lab standard gravimetric solutions.	micromolar (uM)	B
Sr8786	Water column radiogenic strontium ratio 87Sr/86Sr.	unitless	ratio
Sr8786_2sd	Water column radiogenic strontium ratio 87Sr/86Sr 2 standard deviations of replicate measurements.	unitless	ratio
d18O	Water column oxygen-18.	per mil (0/00)	d18O
d18O_2sd	Water column oxygen-18, 2 standard deviations based on replicate standards.	per mil (0/00)	d18O
d11B	Water column bulk boron-11.	per mil (0/00)	d11B
d11B_2sd	Water column bulk boron-11 2 standard deviations of replicate standards.	per mil (0/00)	d11B
pCO2_mean	Water column partial pressure of carbon dioxide calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	microatmospheres (uatm)	pCO2
pCO2_2sd	Water column partial pressure of carbon dioxide uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST Version 0.4.9 (Branson et al., 2024).	microatmospheres (uatm)	pCO2
CO2_mean	Water column dissolved carbon dioxide concentration calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	micromoles per kilogram (umol/kg)	CO2
CO2_sd	Water column dissolved carbon dioxide concentration uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST Version 0.4.9 (Branson et al., 2024).	micromoles per kilogram (umol/kg)	CO2
CO3_mean	Water column dissolved carbonate ion concentration calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	micromoles per kilogram (umol/kg)	carbonate
CO3_2sd	Water column dissolved carbonate ion concentration uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST.	micromoles per kilogram (umol/kg)	carbonate
HCO3_mean	Water column dissolved bicarbonate ion concentration calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	micromoles per kilogram (umol/kg)	bicarbonate
HCO3_2sd	Water column dissolved bicarbonate ion concentration uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST.	micromoles per kilogram (umol/kg)	bicarbonate
omegaC_mean	Water column calcite saturation state, calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 monte carlo simulations.	unitless	OM_ca
omegaC_2sd	Water column calcite saturation state uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST.	unitless	OM_ca
delta_carb	Water column degree of calcite saturation, calculated from CO3_mean - (CO3_mean / omegaC_mean).	micromoles per kilogram (umol/kg)	no_bcodmo_term
delta_carb_err	Water column delta_carb propagated error calculated as delta_carb_err = sqrt(CO3_sd^2 + (CO3_mean/omegaC_mean*omegaC_sd)^2)	micromoles per kilogram (umol/kg)	no_bcodmo_term
pKB_mean	Stoichiometric dissociation (equilibrium) constant for the borate-boric acid system. Calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	unitless	no_bcodmo_term
pKB_2sd	Stoichiometric dissociation (equilibrium) constant uncertainty for the borate-boric acid system, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST Version 0.4.9 (Branson et al., 2024).	unitless	no_bcodmo_term
BOH4_mean	Water column dissolved borate, calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	micromoles per kilogram (umol/kg)	no_bcodmo_term
BOH4_2sd	Water column dissolved borate uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST Version 0.4.9 (Branson et al., 2024).	micromoles per kilogram (umol/kg)	no_bcodmo_term
d11B_BOH4_mean	Water column boron-11 ratio of borate ion,calculated using CBSYST Version 0.4.9 (Branson et al., 2024). Mean of 10,000 Monte Carlo simulations.	per mil (0/00)	no_bcodmo_term
d11B_BOH4_2sd	Water column boron-11 ratio of borate ion uncertainty, calculated as 2 * standard deviation of 10,000 Monte Carlo simulations of CBSYST Version 0.4.9 (Branson et al., 2024).	per mil (0/00)	no_bcodmo_term
Cl_est	Water column dissolved chloride. Estimated from LOESS smoothing of Cl transect data in Tables 1 and 4 of Young et al. (2008). Marine Chemistry. https://doi.org/10.1016/j.marchem.2007.07.010	millimolar (mM)	chloride
SO4_est	Water column dissolved sulfate. Estimated from LOESS smooethin of SO4 transect data in Tables 1 and 4 of Young et al. (2008).Marine Chemistry. https://doi.org/10.1016/j.marchem.2007.07.010	millimolar (mM)	SO4
Sr_est	Water column dissolved strontium. Estimated from LOESS smoothing of Sr data in Tables 1 and 4 of Young et al. (2008).Marine Chemistry. https://doi.org/10.1016/j.marchem.2007.07.010	micromolar (uM)	Sr
K_est	Water column dissolved potassium. Estimated from Na/Cl ratio of seawater using Cl data herein and seawater [K] from Millero et al. (2008). Deep Sea Research Part 1. https://doi.org/10.1016/j.dsr.2007.10.001	millimolar (mM)	K
Na_est	Water column dissolved sodium. Estimated from Na/Cl ratio of seawater using Cl data herein and seawater [Na] from Millero et al. (2008). Deep Sea Research Part 1. https://doi.org/10.1016/j.dsr.2007.10.001	millimolar (mM)	Na
adjusted_Na	Water column dissolved sodium, determined by adjusting column (Na) to reduce column (charge_imbalance) value within MarChemSpec (Clegg & Turner, 2023).	millimolar (mM)	Na
charge_imbalance	Solution charge imbalance resulting from MarChemSpec (Clegg & Turner, 2023) calculation of pH using parameters in this file.	moles	no_bcodmo_term
pH_MarcChemSpec	Water column pH calculated from MarChemSpec (Clegg & Turner, 2023) using Pitzer constants.	total scale	pH