Water-column environmental variables and accompanying discrete CTD measurements collected offshore the U.S. Mid- and South Atlantic (ver. 2.0, July 2022)

Frequently anticipated questions:

• What does this data set describe?
  1. How might this data set be cited?
  2. What geographic area does the data set cover?
  3. What does it look like?
  4. Does the data set describe conditions during a particular time period?
  5. What is the general form of this data set?
  6. How does the data set represent geographic features?
  7. How does the data set describe geographic features?
• Who produced the data set?
  1. Who are the originators of the data set?
  2. Who also contributed to the data set?
  3. To whom should users address questions about the data?
• Why was the data set created?
• How was the data set created?
  1. From what previous works were the data drawn?
  2. How were the data generated, processed, and modified?
  3. What similar or related data should the user be aware of?
• How reliable are the data; what problems remain in the data set?
  1. How well have the observations been checked?
  2. How accurate are the geographic locations?
  3. How accurate are the heights or depths?
  4. Where are the gaps in the data? What is missing?
  5. How consistent are the relationships among the data, including topology?
• How can someone get a copy of the data set?
  1. Are there legal restrictions on access or use of the data?
  2. Who distributes the data?
  3. What's the catalog number I need to order this data set?
  4. What legal disclaimers am I supposed to read?
  5. How can I download or order the data?
• Who wrote the metadata?

What does this data set describe?

1. How might this data set be cited?
   Prouty, Nancy G., and Baker, Miranda C., 2021, Water-column environmental variables and accompanying discrete CTD measurements collected offshore the U.S. Mid- and South Atlantic (ver. 2.0, July 2022): data release DOI: 10.5066/P9K2GOAL, U.S. Geological Survey, Pacific Coastal and Marine Science Center, Santa Cruz, California.

   Online Links:

   • https://doi.org/10.5066/P9K2GOAL
   • https://www.sciencebase.gov/catalog/item/6281d019d34e3bef0c9a3b12

2. What geographic area does the data set cover?

   West_Bounding_Coordinate: -83.9978
   East_Bounding_Coordinate: -74.5177
   North_Bounding_Coordinate: 37.2404
   South_Bounding_Coordinate: 29.2495
   

3. What does it look like?
4. Does the data set describe conditions during a particular time period?

   Beginning_Date: 01-Sep-2017

   Ending_Date: 18-Apr-2019

   Currentness_Reference:

   Ground condition at time data were collected.

5. What is the general form of this data set?

   Geospatial_Data_Presentation_Form: comma-delimited text
   

6. How does the data set represent geographic features?
   1. How are geographic features stored in the data set?
      This is a Point data set. It contains the following vector data types (SDTS terminology):
      • Point (207)
   2. What coordinate system is used to represent geographic features?
      Horizontal positions are specified in geographic coordinates, that is, latitude and longitude. Latitudes are given to the nearest 0.0001. Longitudes are given to the nearest 0.0001. Latitude and longitude values are specified in Decimal degrees. The horizontal datum used is D_WGS_1984.
      The ellipsoid used is D_WGS_1984.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257224.
      
7. How does the data set describe geographic features?

   A comma-delimited text file with the first line being a header line.

   Comma separated values containing data points from CTD water column profiles with cruise, ship, site, station, cast, Niskin bottle, sample ID, date of collection, bottle depth (m), latitude, longitude, temperature, conductivity, pressure, oxygen, turbidity, fluorescence, altimeter, salinity, and ctd depth, and output from seawater geochemistry lab analysis from seawater sampling from individual Niskin bottles. (Source: Producer defined.)

   Cruise

   Name of cruise on which samples and measurements were collected. The name of the cruise may contain a ship abbreviation and year (BCMM-2018=Brooks McCall and [year]; PC-1704=R/V Pisces and [20XX year, month]; Ron Brown=RB1903 and [20XX year, month], AT41=R/V Atlantis and sequential cruise number), and ENG615 ADEON=R/V Endeavor, cruise EN615 for the Atlantic Deepwater Ecosystem Observatory Network [ADEON]). (Source: Producer defined) List of cruise names

   Ship

   Name of ship on which samples and measurements were collected. (Source: Producer defined) List of ship names

   Site

   Name of site for which samples and measurements were collected. (Source: Producer defined) List of site names

   CTD Station

   Name of CTD stations based on ship name (BCMM=Brooks McCall; PC=R/V Pisces; AT=R/V Atlantis) and/or CTD sequence (e.g., CTD12) where samples and measurements were collected. (Source: Producer defined) List of CTD stations.

   CTD number

   Number of CTD cast (Source: Producer defined.)

   Range of values
   Minimum:	1
   Maximum:	13
   Units:	unitless
   Resolution:	1

   Niskin bottle number

   Number of Niskin bottle number (Source: Producer defined.)

   Range of values
   Minimum:	1
   Maximum:	24
   Units:	unitless
   Resolution:	1

   Sample ID

   Sample ID based on ship abbreviation (BCMM=Brooks McCall; PC=R/V Pisces; AT=R/V Atlantis) and CTD number of cast where samples were collected, niskin bottle number (e.g., N3) or water sample number (e.g., W049); or site abbreviation (BLE=Blake Escarpment; JAX=Jacksonville; CHMB=Charleston Bump; SAV=Savannah; WIL=Wilmington; VAC=Virginia Inter-Canyon), and sequential sample number. (Source: Producer defined.) List of sampled IDs names

   Date of collection

   Date [MM/DD/YY] (Source: Producer defined.)

   Range of values
   Minimum:	9/1/17
   Maximum:	4/18/19

   Latitude

   Latitude of sample location (Source: Producer defined.)

   Range of values
   Minimum:	29.2495
   Maximum:	37.2404
   Units:	decimal degrees
   Resolution:	0.0001

   Longitude

   Longitude of sample location (Source: Producer defined.)

   Range of values
   Minimum:	-83.9978
   Maximum:	-74.5177
   Units:	decimal degrees
   Resolution:	0.0001

   Depth

   Water depth of deep-sea coral collection (Source: producer defined)

   Range of values
   Minimum:	0
   Maximum:	2267
   Units:	meters
   Resolution:	1

   Temperature

   Temperature [ITS-90, deg C]. Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	-1.3468
   Maximum:	30.0084
   Units:	degrees Celsius
   Resolution:	0.0001

   Conductivity

   Conductivity (mS/cm). Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	32.83334
   Maximum:	60.24224
   Units:	millisiemens per centimeter
   Resolution:	0.00001

   Pressure

   Pressure (decibars). Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	5.034
   Maximum:	1390.201
   Units:	decibars
   Resolution:	0.001

   Sbeox0

   Oxygen, SBE 43 (mg/l). Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	3.7014
   Maximum:	21.7075
   Units:	milligrams per liter
   Resolution:	0.0001

   Turbidity

   Turbidity, WET Labs ECO [NTU]. Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	0.0041
   Maximum:	29.5419
   Units:	Nephelometricy Turbidity Units
   Resolution:	0.0001

   Fluorescence

   Fluorescence, WET Labs ECO-AFL/FL [mg/m^3]. Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	0.0006
   Maximum:	10.3949
   Units:	miligrams per cubic meter
   Resolution:	0.0001

   AltM

   Altimeter [m] (Source: producer defined. Values of -9999 indicate the parameter was not measured.)

   Range of values
   Minimum:	0.04
   Maximum:	1480.89
   Units:	meters
   Resolution:	0.01

   Salinity

   Salinity, Practical [PSU]. Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	31.7899
   Maximum:	36.9497
   Units:	practical salinity units (PSU)
   Resolution:	0.0001

   DepSM

   Depth [salt water, m]. Values of -9999 indicate the parameter was not measured. (Source: producer defined)

   Range of values
   Minimum:	2.014
   Maximum:	2193.720
   Units:	meters
   Resolution:	0.001

   Phosphate

   Dissolved inorganic phosphate concentration. Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in inorganic chemistry)

   Range of values
   Minimum:	0.00
   Maximum:	3.11
   Units:	micromole per liter of seawater
   Resolution:	0.01

   Silicate

   Dissolved inorganic silicate concentration. (Source: standard reporting value in inorganic chemistry)

   Range of values
   Minimum:	0.12
   Maximum:	19.05
   Units:	micromole per liter of seawater
   Resolution:	0.01

   Nitrate+Nitrite

   Dissolved inorganic nitrate and nitrite concentration. (Source: standard reporting value in inorganic chemistry)

   Range of values
   Minimum:	0.00
   Maximum:	29.97
   Units:	micromole per liter of seawater
   Resolution:	0.01

   ammonium

   Dissolved inorganic ammonium concentration. Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in inorganic chemistry.)

   Range of values
   Minimum:	0.00
   Maximum:	1.23
   Units:	micromole per liter of seawater
   Resolution:	0.01

   Nitrate delta-N-15

   delta-N-15 is a measure of the ratio of stable isotopes Nitrogen-15:Nitrogen-14 in nitrate, reported in parts per thousand (per mil). Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	1.86
   Maximum:	12.87
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Nitrate delta-O-18

   delta-O-18 is a measure of the ratio of stable isotopes Oxygen-18:Oxygen-16 in nitrate, reported in parts per thousand (per mil). Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	1.51
   Maximum:	2.52
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Water delta-O-18

   delta-O-18 is a measure of the ratio of stable isotopes Oxygen-18:Oxygen-16 in water, reported in parts per thousand (per mil). Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	-0.75
   Maximum:	1.16
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   water delta-D

   delta-D is a measure of the ratio of stable isotopes Hydrogen (deuterium)-2:Hydrogen-1 in water, reported in parts per thousand (per mil). Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	-6.86
   Maximum:	8.39
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Fraction Modern

   Fraction modern is a measurement of the deviation of the delta-Carbon-14/delta-Carbon-12 ratio of a sample from modern carbon (Stuiver and Polach, 1977). Values of -9999 indicate the parameter was not measured. (Source: defined in Stuiver and Polach (1977))

   Range of values
   Minimum:	0.9647
   Maximum:	1.0718
   Units:	unitless
   Resolution:	0.0001

   Fraction Modern (error)

   Fraction modern (error) is a measurement of the deviation of the delta-Carbon-14/delta-Carbon-12 ratio of a sample from modern carbon (Stuiver and Polach, 1977). Values of -9999 indicate the parameter was not measured. (Source: defined in Stuiver and Polach (1977))

   Range of values
   Minimum:	0.0019
   Maximum:	0.0031
   Units:	unitless
   Resolution:	0.0001

   Conventional Radiocarbon Age

   Conventional Radiocarbon Age calculated using the radiocarbon decay equation (Stuiver and Polach, 1977). >Modern indicates a FM>1 with sample age after 1950 (Stuiver and Polach, 1977). Values of -9999 indicate the parameter was not measured. (Source: defined in Stuiver and Polach (1977))

   Range of values
   Minimum:	35
   Maximum:	290
   Units:	years
   Resolution:	5

   Conventional Radiocarbon Age (error)

   Standard error for Conventional Radiocarbon Age. Values of -9999 indicate the parameter was not measured. (Source: Producer defined.)

   Range of values
   Minimum:	15
   Maximum:	20
   Units:	years
   Resolution:	1

   delta-C-13

   delta-C-13 is a measure of the ratio of stable isotopes Carbon-13:Carbon-12, reported in parts per thousand (per mil). Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in isotope chemistry)

   Range of values
   Minimum:	0.40
   Maximum:	0.99
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Delta-C-14

   The relative difference between the absolute international standard (base year 1950) and sample activity corrected for age and delta-Carbon-13. Values of -9999 indicate the parameter was not measured. (Source: defined in Stuiver and Polach (1977))

   Range of values
   Minimum:	-43.20
   Maximum:	63.01
   Units:	parts per thousand (per mil)
   Resolution:	0.01

   Dissolved Inorganic Carbon

   The sum of inorganic carbon species in a solution (carbon dioxide, carbonic acid, bicarbonate anion, and carbonate. Values of -9999 indicate the parameter was not measured. (Source: standard reporting value in inorganic chemistry)

   Range of values
   Minimum:	1.70
   Maximum:	2.15
   Units:	millimole per kilogram
   Resolution:	0.01

   Entity_and_Attribute_Overview:

   The first line of the comma-delimited text file is a header line.

   Entity_and_Attribute_Detail_Citation: U.S. Geological Survey
   

Who produced the data set?

1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)
   • Nancy G. Prouty
   • Miranda C. Baker
2. Who also contributed to the data set?
   Ken Marchus (University of California, Santa Barbara), John Schiff and Chris Maupin (Texas A&M), Natasha Vokhshoori (University of California, Santa Cruz)
3. To whom should users address questions about the data?
   U.S. Geological Survey, Pacific Coastal and Marine Science Center

   Attn: PCMSC Science Data Coordinator

   2885 Mission Street

   Santa Cruz, CA
   

   831-427-4747 (voice)

   pcmsc_data@usgs.gov

Why was the data set created?

How was the data set created?

1. From what previous works were the data drawn?

   nutrients (source 1 of 4)

   University of California at Santa Barbara, Marine Science Institute, 2019, Seawater nutrient analyses.

   Online Links:

   • http://msi.ucsb.edu/services/analytical-lab/seawater-nutrients-fia

   Type_of_Source_Media: seawater lab samples
   Source_Contribution:

   Flow injection analysis for dissolved nutrient (nitrate+nitrite, ammonium, phosphate, and silicate) concentrations.

   Nitrate delta-N-15 and delta-0-18 (source 2 of 4)

   University of California, Davis Stable Isotope Facility, 2020, nitrate stable nitrogen isotope analysis.

   Type_of_Source_Media: seawater lab samples
   Source_Contribution:

   The denitrifier method of Sigman and others (2001) was used, and isotope values were measured using a Thermo Finnigan MAT 252 coupled with a GasBench II interface. Isotope values are presented in per mil with respect to AIR for delta-N-15 and VSMO for delta-O-18.

   radiocarbon (source 3 of 4)

   National Ocean Sciences Accelerator Mass Spectrometry (NOSAMS) facility, 2019, Seawater radiocarbon analysis.

   Online Links:

   • https://www.whoi.edu/nosams/Submitting_Guidelines

   Type_of_Source_Media: seawater lab samples
   Source_Contribution:

   An accelerator mass spectrometer (AMS) was used to measure inorganic radiocarbon

   Oxygen (delta-O-18) and Hydrogen (delta-D) analysis of water (source 4 of 4)

   Texas A&M University at College Station Stable Isotope Geosciences Facility, 2020, Seawater isotope analysis.

   Online Links:

   • https://stableisotope.tamu.edu/about/index.html

   Type_of_Source_Media: seawater lab samples
   Source_Contribution:

   A Picarro Isotopic Water Analyzer was used to measure stable isotopes of oxygen and hydrogen in water.

2. How were the data generated, processed, and modified?

   Date: 2020 (process 1 of 4)

   Water samples were collected using a Niskin bottle rosette apparatus at different depths throughout the water column. Simultaneous conductivity, salinity, and depth (CTD) data were collected with a SeaBird SBE-9 CTD profiler at each Niskin bottle sample depth. The CTD data were collected with a SeaBird SBE-9 CTD Profile. Data collected when instruments were out of the water were removed during post-processing. Data from depths at which Niskin bottles were tripped was copied from individual cruise datafiles into a collated datafile. Conductivity measurements from ENG615 cruise were converted from siemens per meter to millisiemens per centimeter. Oxygen concentrations from ENG615 were converted from millimolar per liter to milligram per liter using the molar mass of oxygen gas. Oxygen concentrations from the AT41 and RB1903 cruises were converted from micromolar per kilogram to milligram per liter using the molar mass of oxygen gas and the density of seawater measured by the CTD. PC1704 pressure values were converted from pressure square inch to decibars.

   Date: 2020 (process 2 of 4)

   Seawater samples were analyzed by several different labs (see Sources) for different variables. Data from all seawater lab analyses were combined into a single document. Empty cells are designated by -9999 indicating no analysis was performed. Data sources used in this process:

   • nutrients
   • radiocarbon
   • Nitrate delta-N-15 and delta-0-18
   • Oxygen (delta-O-18) and Hydrogen (delta-D)

   Data sources produced in this process:

   • lab data

   Date: 2020 (process 3 of 4)

   CTD data and water column variables were combined based on depths into a single document (DEEPSEARCH_CTD_BTLDATA_v2.0.csv). Data sources used in this process:

   • lab data
   • CTD data

   Date: Jun-2022 (process 4 of 4)

   Correction was made to version 1.0 data to correct the attribute column header from “Ammonia” to “Ammonium.” No data values were changed. Versioning details are documented in the accompanying VersionHistory_P9K2GOAL.txt file.

3. What similar or related data should the user be aware of?
   Stuiver, M., and Polach, H.A., 1977, Discussion reporting of 14C data.

   Online Links:

   • https://doi.org/10.1017/S0033822200003672

   Other_Citation_Details:

   Stuiver, M., and Polach, H.A., 1977, Discussion reporting of 14C data: Radiocarbon, v. 19, pp. 355-363.

   Sigman, D.M., Casciotti, K.L., Andreani, M., Barford, C., Galanter, M., and Bohlke, J.K., 2001, A bacterial method for the nitrogen isotopic analysis of nitrate in seawater and freshwater.

   Online Links:

   • https://doi.org/10.1021/ac010088e

   Other_Citation_Details:

   Sigman, D.M., Casciotti, K.L., Andreani, M., Barford, C., Galanter, M., Bohlke, J.K., 2001, A bacterial method for the nitrogen isotopic analysis of nitrate in seawater and freshwater: Analytical Chemistry, v. 73, 4145-4153.

How reliable are the data; what problems remain in the data set?

1. How well have the observations been checked?
   All geochemistry data were calibrated against known standards. The CTD was calibrated according to the Sea-Bird user manual.
2. How accurate are the geographic locations?
   A formal accuracy assessment of the horizontal positional information in the data set has not been conducted. The horizontal accuracy was determined with the ships’ GPS navigation, with a stated accuracy of less than 5 m.
3. How accurate are the heights or depths?
   A formal accuracy assessment of the vertical positional information in the data set has not been conducted. Depth was determined using a SeaBird SBE-4 CTD digiquartz pressure sensor with a stated accuracy of 0.015 percent.
4. Where are the gaps in the data? What is missing?
   Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the metadata for each part of this data release carefully for additional details. Dataset is considered complete for the information presented, as described in the abstract. Users are advised to read the metadata for each part of this data release carefully for additional details.
5. How consistent are the relationships among the observations, including topology?
   No formal logical accuracy tests were conducted.

How can someone get a copy of the data set?

1. Who distributes the data set? (Distributor 1 of 1)
   
   U.S. Geological Survey - ScienceBase

   Denver Federal Center, Building 810, Mail Stop 302

   Denver, CO
   

   1-888-275-8747 (voice)

   sciencebase@usgs.gov
2. What's the catalog number I need to order this data set? These data are available in a .csv file (DEEPSEARCH_CTD_BTLDATA_v2.0.csv) which contains seawater chemical analysis and CTD data for all collected water samples.
3. What legal disclaimers am I supposed to read?
   Unless otherwise stated, all data, metadata and related materials are considered to satisfy the quality standards relative to the purpose for which the data were collected. Although these data and associated metadata have been reviewed for accuracy and completeness and approved for release by the U.S. Geological Survey (USGS), no warranty expressed or implied is made regarding the display or utility of the data on any other system or for general or scientific purposes, nor shall the act of distribution constitute any such warranty.
4. How can I download or order the data?
   • Availability in digital form:

     Data format:	.csv file in format comma-delimited text (version 14.7.7) Size: 0.058
     Network links:	https://www.sciencebase.gov/catalog/item/6281d019d34e3bef0c9a3b12 hhttps://doi.org/10.5066/P9K2GOAL

   • Cost to order the data: None.

5. What hardware or software do I need in order to use the data set?
   These data can be viewed with any text editor software.

Who wrote the metadata?

Dates:

Last modified: 13-Jul-2022

Metadata author:

U.S. Geological Survey, Pacific Coastal and Marine Science Center

Attn: PCMSC Science Data Coordinator

2885 Mission Street

Santa Cruz, CA

831-427-4747 (voice)

pcmsc_data@usgs.gov

Metadata standard:

Content Standard for Digital Geospatial Metadata (FGDC-STD-001-1998)