Dataset: Carbon Flux Explorer CCE_LTER P1706 - Imagery
Deployment: RR1710

View Data: For data, See Dataset Metadata Page: https://www.bco-dmo.org/dataset/825076

Principal Investigator:

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

Contact:

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

BCO-DMO Data Manager:

Karen Soenen (Woods Hole Oceanographic Institution, WHOI BCO-DMO)

Project:

California Current Ecosystem Long Term Ecological Research site (CCE LTER)

Carbon Flux Explorer Development (C-SNOW Development)

Carbon Sedimentation In the Ocean Watercolumn (C-SNOW): Calibration (C-SNOW)

Version:

Deployment Synonyms:

LTER CCE-P1706, CCE-P1706, CCE LTER P1706, P1706

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Description

Original transmitted-light imagery and processed attenuance images of sinking particles observed by autonomous Carbon Flux Explorers deployed 100-500m in the California Current Regime, during the CCE-LTER process study (P1706) between June 2 and July 1, 2017.

These data are submitted with this manuscript: Bourne et al., 2020

Methods & Sampling

Dataset acquisition description

The expedition followed a newly formed filament of upwelled water in a region bounded by 33.5N, 123.5W and 35.2N, 120.8W.

Sample attenuance calculation. Transmitted light color images were normalized by an in-situ composite image of the clean sample stage following Bishop et al., 2016 yielding a map of fractional transmission corrected for inhomogeneities of the light source. Attenuance (ATN) values were then calculated by taking the -log10 of the normalized image. Results were saved as bmp formatted images in attenuance units where counts in each 8- bit (red, green, blue) color plane are scaled so that 100 counts = 1 attenuance unit.

The Carbon Flux Explorer is built on a standard ARGO style float, called the Sounding Oceanographic Lagrangian Explorer (SOLO and SOLO-II). The float is the buoyancy engine for the CFE and also manages all satellite communication of data from the CFE. The top of the float has an integrated Seabird CTD system. Temperature, pressure, and salinity data are read in bursts at 10 minute intervals as the CFE is monitoring flux at depth. These data are merged with the imagery meta data.

Data Processing Description

Dataset Processing Description

The software package ImageJ 1.52 (IJ, National Institutes of Health) was used for particle size analysis. Fortran codes were written for secondary data processing.

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-1538686	NSF Division of Ocean Sciences

Instruments

Carbon Flux Explorer

Supplied Description:

The CFE and the operation of its particle flux sensing Optical Sedimentation Recorder (OSR) have been discussed in detail in Bishop et al. (2016). CFE has a design mission capability of 8 months of hourly operations (16 months @ 2 hours …) and has been demonstrated by deployments of 40 days; CFE design depth is 1500m and it has been proven to 1000 m. The system has demonstrated operations in high sea states.

Briefly, once deployed, the CFE dives below the surface make particle flux observations at target depths as it drifts with currents. The OSR wakes once the CFE has reached the target depth. On first wake-up of a given CFE dive, the sample stage is flushed with water and images of the particle-free stage are obtained. Particles settle through a 1-cm opening hexagonal celled light baffle into a high-aspect ratio funnel assembly before landing on a 2.54 cm diameter glass sample stage. At 25-minute intervals, particles are imaged at 13 µm pixel resolution in three lighting modes: dark field, transmitted and transmitted-cross polarized.

Instrument Type

Generic Name: Carbon Flux Explorer

Acronym: CFE

Generic Description:

The Carbon Flux Explorer (CFE) is designed to perform sustained high-frequency observations of POC and PIC sedimentation within the upper kilometer (or twilight zone) of the ocean for seasons to years and to operate in an observational context not dependent on ships. The CFE melds the concept of current-following, sample-collecting neutrally buoyant sediment traps with photographic imaging of the particles as they are deposited in a sediment trap.

The CFE and the operation of its particle flux sensing Optical Sedimentation Recorder (OSR) have been discussed in detail in Bishop et al. (2016). CFE has a design mission capability of 8 months of hourly operations (16 months @ 2 hours) and has been demonstrated by deployments of 40 days; CFE design depth is 1500m and it has been proven to 1000 m. The system has demonstrated operations in high sea states.

Diagram: https://datadocs.bco-dmo.org/docs/302/C-SNOW/data_docs/CFE_CFE-Cal.png

Bishop, J. K. B., Fong, M. B., and Wood, T. J.: Robotic observations of high wintertime carbon export in California coastal waters, Biogeosciences, 13, 3109–3129, https://doi.org/10.5194/bg-13-3109-2016, 2016.

Bourne, H. L., Bishop, J. K. B., Wood, T. J., Loew, T. J., and Liu, Y.: Carbon Flux Explorer optical assessment of C, N and P fluxes, Biogeosciences, 16, 1249–1264, https://doi.org/10.5194/bg-16-1249-2019, 2019

CTD Sea-Bird 41

Supplied Name: SBE 41 CTD

Supplied Description:

The CTD used with the SOLO floats is the Seabird SBE 41 CTD.

Salinity ± 0.0035 psu
Pressure Initial Accuracy: ± 2 dbar
Temperature Accuracy: ± 0.002 °C

Instrument Type

Generic Name: CTD Sea-Bird 41

Acronym: CTD SBE 41

Community Identifier: http://vocab.nerc.ac.uk/collection/L05/current/130/

Generic Description:

The Sea-Bird SBE 41 CTD module was originally developed in 1997 for integration with sub-surface oceanographic floats. It uses MicroCAT Temperature, Conductivity, and Pressure sensors.

Sounding Oceanographic Lagrangian Observer

Supplied Name: SOLO

Supplied Description:

Instrument Type

Generic Name: Sounding Oceanographic Lagrangian Observer

Acronym: SOLO

Generic Description:

A standard ARGO style float, called the Sounding Oceanographic Lagrangian Explorer (SOLO and SOLO-II).

SOLO floats are drifting instruments and have the ability to change their own buoyancy. After deployment it moves with the ocean currents and can, therefore, travel long distances on their own without the need of a ship or a person to handle them. They are programmed to come to the ocean surface at regular intervals to transmit their data and position to orbiting satellites. The float then sinks again, continuing the process.

To control the buoyancy of the float, a small amount of oil is contained within the float. When the float is submerged, all of the oil is kept entirely within the hull. When it is time to rise to the surface, the oil is pumped into an external rubber bladder that expands. Since the weight of the float does not change but its volume increases when the bladder expands, the float becomes more buoyant and floats to the surface. Similarly, when the float is on the surface and it is time to submerge, the oil is withdrawn from the bladder into the hull of the float and the buoyancy decreases.

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
cycle	CCE cycle number = our location number (range 1 to 4)	unitless	sample_descrip
cfeid	Carbon Flux Explorer Identity (CFE00X) where X is serial number (1 through 4)	unitless	inst_model
cfeno	Carbon Flux Explorer (CFE) serial number (1 through 4)	unitless	inst_model
dive	CFE dive number	unitless	sample_descrip
ISO_DateTime_UTC	Datetime of image acquisition in ISO format (yyyy-mm-ddThh:mm:ssZ) in UTC zone	yyyy-MM-dd'T'HH:mm:ss	date_utc
jday	Day: Jan 1 = 1, use to correlate with satellite imagery	unitless	days
ddays	decimal days since Jan 1 2017 at 0000 UTC, ddays = 0.5 on Jan 1 2017 at 1200UTC, ADCP data use same time	unitless	days
driftdays	CTD obs decimal days since Jan 1 2017 at 0000 UTC, ddays = 0.5 on Jan 1 2017 at 1200UTC, ADCP data use same time	unitless	days
lon	Decimal Longitude (negative for west)	decimal degrees	lon
lat	Decimal Latitude (negative for south)	decimal degrees	lat
press	SOLO CTD pressure	dbar	press
pressflag	SOLO Data (0 - profiling or unstable; 1 during flux measurement; 4 single value for dive; 5 SOLO at surface)	unitless	sample_descrip
temp	SOLO CTD insitu temperature	degrees Celcius	temperature
sal	SOLO CTD salinity	PSU	sal
cm_sec	SOLO Rate of depth change over 10 minute intervals	cm s-1	sample_descrip
diveimage_seq	dive image number	unitless	sample_descrip
cleanflag	1 = means taken seconds after a cleaning cycle; 0 = images after cleaning; -1 means failed clean; -2 image taken at start of dive before first stage cleaning	unitless	sample_descrip
class_ATN	UPPER CASE 'ATN' if useful OR lowercase 'bck' if non useful.	unitless	sample_descrip
class_BCK	UPPER CASE 'BCK' if useful OR lowercase 'bck' if non useful.	unitless	sample_descrip
illum	illumination mode (bck=transmitted light, led=darkfield illumnation, pol crosspolarized transmission, pl2=pol at longer exposure time)	unitless	sample_descrip
sensor	CFE enginnering information: SUMIX imager serial number	unitless	inst_model
exp_msec	Imager exposure time in milli seconds	s*10^-3	sample_descrip
b_gain	Imager gain settinng blue channnel	unitless	sample_descrip
g_gain	imager gain settinng green channnel	unitless	sample_descrip
r_gain	imager gain setting red channel	unitless	sample_descrip
therm	instrument temperature (C) NOT CALIBRATED	unitless	sample_descrip
iqual	flag (1 = image is useful for flux information ; 4 = image is not useful since the CFE was profiling or was stuck at the surface)	unitless	sample_descrip
flatflag_bck_images	flag (1 = image has been corrected for non uniformity of illumimation; 0 = no corection)	unitless	sample_descrip
flatflag_atn_images	flag (1 = image has been corrected for non uniformity of illumimation; 0 = no corection)	unitless	sample_descrip
filename_bck	Filename of BCK images	unitless	file_name
filename_atn_images	Filename of ATN image	unitless	file_name

Database

Contribute Data

Dataset: Carbon Flux Explorer CCE_LTER P1706 - Imagery
Deployment: RR1710

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: Carbon Flux Explorer CCE_LTER P1706 - ImageryDeployment: RR1710

Dataset acquisition description

Dataset Processing Description

Dataset: Carbon Flux Explorer CCE_LTER P1706 - Imagery
Deployment: RR1710