Dataset: GP17 ODF CTD optics data Beam Attenuation Coefficient, Oxygen, and Fluorencence

Name: Recalculated and filtered Transmissometer Beam Attenuation Coefficient values for the ODF CTD from the GEOTRACES GP17-OCE cruise aboard R/V Roger Revelle (RR2214) from December 2022 to January 2023
Published: 2025-01-28
Keywords: GEOTRACES, particulate inorganic carbon, in-water optical proxies, particulate organic carbon, oceans

View Data: Data not available yet

Cite This Dataset

Spatial Extent: N:-19.9998 E:-75.0972 S:-67.0002 W:-152.0002

Temporal Extent: 2022-12-04 - 2023-01-24

Project:

Autonomous Ocean Carbon Observer Development and Calibration (OCO Development)

Principal Investigator:

James K.B. Bishop (University of California-Berkeley, UC Berkeley)

Scientist:

Benjamin Twining (Bigelow Laboratory for Ocean Sciences)

BCO-DMO Data Manager:

Shannon Rauch (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Version:

Version Date:

2025-01-28

Restricted:

Validated:

Current State:

Data not available

Recalculated and filtered Transmissometer Beam Attenuation Coefficient values for the ODF CTD from the GEOTRACES GP17-OCE cruise aboard R/V Roger Revelle (RR2214) from December 2022 to January 2023

Abstract:

This dataset contains recalculated and filtered Transmissometer Beam Attenuation Coefficient values for the ODF CTD from the GEOTRACES GP17-OCE cruise aboard R/V Roger Revelle (RR2214) from December 2022 to January 2023. The primary data file provided here contains the average of all optical data profiles at each station for 0-500 meters (m) depth (depth intervals of 5-meters). Data for the full depth of the water column (6000 meters) are also included as supplemental files.

Expand/Collapse All

Methods & Sampling

Calculated Beam Attenuation coefficient from despiked 10-second averaged data sets. The resulting data are further averaged over 5-meter intervals.

Data Processing Description

The data from Transmissometer 1874 was recalculated using

# dt=temp-t391 ; calculated difference between water temperature and instrument temperature

# cst1874c=(cst1874-0.0024)/cst1874r ; cst1874r is a temperature response function derived from WETLabs thermal cycling tests. ; 0.0024 is the blocked beam voltage on the CTD

# cst1874cc=cst1874c+dt/1300 ; corrects for hysteresis in the thermoclone

# cst1874tr=cst1874cc/(cst1874_NETVrefUSE) ; transmission ratio ; cst1874_NETVrefUSE is the zero corrected reading the transmissometer would have in particle free seawater.

# cp1874=-4*ln(cst1874tr) ; calculation of beam attenuation coefficient

the data from Fluorometer Voltages was offset and multiplied to agree with Seapoint Fluorometer data on the GTC CTD. Relative units.

The following GEOTRACES parameter names have been registered in DOoR:

CTDBEAMCP_T_VALUE_SENSOR::kpdsqt

BCO-DMO Processing

- Imported original file "GP17_ODF_CTD_Cast_Profiles_0500.csv" into the BCO-DMO system.
- Converted station, cast, and year columns to integers.
- Calculated ISO date-time field (UTC) from the jdays column.
- Saved the final file as "949808_v1_gp17_odf_ctd_optics_data_cast_profiles_0500.csv".

More Information about this dataset

Funding Sources

Funding Source	Award Number
NSF Division of Ocean Sciences	OCE-2123942
NSF Division of Ocean Sciences	OCE-1736601
NSF Division of Ocean Sciences	OCE-1657781
NSF Division of Ocean Sciences	OCE-2023315

Deployments

Deployment	Synonyms	Start Date	Platform	Investigator
RR2214	GP17 GP17-OCE 33RR20221201	2022-12-01	R/V Roger Revelle	Benjamin Twining (Chief Scientist) Gregory A. Cutter (Co-Chief Scientist) Jessica N. Fitzsimmons (Co-Chief Scientist)	data info

Instruments

Transmissometer

Supplied Name:

Supplied Description:

Sensor CST1874

Instrument Type

Generic Name: Transmissometer

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/124/

Generic Description:

A transmissometer measures the beam attenuation coefficient of the lightsource over the instrument's path-length. This instrument designation is used when specific manufacturer, make and model are not known.

Parameters

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

Supplied Name	Supplied description	Supplied Units	Standard Name
station	station number	unitless	station
cast	cast sequence on station	unitless	cast
updn	flag [-1 = downcast; 1 = upcast]	unitless	cast_type
lat	decimal latitude (north positive)	decimal degrees	lat
lon	decimal longitude (east positive	decimal degrees	lon
year	year	unitless	year
jdays	ordinal days in 2018	unitless	julian_day
ISO_DateTime_UTC	Date and time (UTC) in ISO 8601 format Format: %Y-%m-%dT%H:%M:%SZ	unitless	ISO_DateTime_UTC
press	Pressure [Digiquartz]	decibars (db)	press
depth	Depth [salt water, m]	meters (m)	depth
temp	CTD temperature [ITS-90 deg C]	degrees Celsius	temp
theta	potential temperature [deg C]	degrees Celsius	potemp
sal	Salinity - Practical [PSU]	PSU	sal
sigth	potential density anomaly	unitless	sigma_0
cp1874	Particle Beam Attenuation Coefficient [PPM m-1] from SENSOR CST1874 Filtered	parts per million per meter (ppm m-1)	beam_cp
cp1874_sd	Particle Beam Attenuation Coefficient Standard Deviation [PPM m-1] from SENSOR CST1874 Filtered	parts per million per meter (ppm m-1)	beam_cp
flwl_corr	Fluorescence WET Labs ECO-AFL/FL	?	fluor
flwl_corr_sd	Fluorescence_sd WET Labs ECO-AFL/FL	?	fluor
o2	Oxygen, SBE 43 [umol/kg]	micromoles per kilogram (umol/kg)	O2
trackdist_km	kilometers track distance from station 1	kilometers (km)	len_track

Status message

Database

Contribute Data

Dataset: GP17 ODF CTD optics data Beam Attenuation Coefficient, Oxygen, and Fluorencence