Dataset: CTD data from Bongo plankton net tows
Deployment: BBB2102

CTD up-cast data

View Data: For data, See Dataset Metadata Page: https://www.bco-dmo.org/dataset/871003

Principal Investigator:

Brice X. Semmens (University of California-San Diego, UCSD-SIO)

Co-Principal Investigator:

Michael R. Landry (University of California-San Diego, UCSD-SIO)

Contact:

Rasmus Swalethorp (University of California-San Diego, UCSD-SIO)

BCO-DMO Data Manager:

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

Project:

RAPID: Understanding the unprecedented anchovy response to warm-water conditions in the California Current (RAPID Anchovy Response)

Version:

Expand/Collapse All

Description

Methods & Sampling

Dataset acquisition description

This study is carried out within the temperate to subtropical Southern California Bight and surrounding coastal areas between 32° and 35° N, and 117° and 120° W. Specific locations sampled fall within the CalCOFI and CCE-LTER programs quarterly survey grid from lines 76.7 to 93.4 and stations 26 to 55.

Sampling stations were sampled ~2-7 days after the California Cooperative Oceanic Fisheries Investigations (CalCOFI) & California Current Ecosystem Long-term Ecological Research Program (CCE-LTER) Fall 2020 and Winter 2021 surveys had sampled the same stations. The CalCOFI & CCE-LTER Spring 2021 survey was delayed by ~2 weeks relative to this project.

Each cruise no is composed of one or more day trips using one of two research vessels (RV Bob & Betty Beyster or RV Shearwater). The two-three letters indicate the research vessel, the four digits indicates YYMM.

CTD was attached to a wire and positioned just above a 71cm diameter dual Bongo plankton net system to record depth and physical variables during horizontal net tows at a ship speed of 1.5-2.5 knots down to 13-62 m depth. The CTD was not allowed to acclimate before deployment and the positioning of the CTD caused substantial interference from water mixing and air bubble release from the nets during the down-cast. Therefore, only the up-cast is reported. Following initial data processing (see Data Processing) up-cast Depth ~ Temperature, Salinity, Density profiles were inspected and went through two series of point checking where outlier values were manually removed.

The SonTek CastAway-CTD model CC1403002 was used. Temperature and conductivity sensor calibration date 4/3/2015. Pressure sensor calibration date 3/13/2015.

Data Processing Description

Dataset Processing Description

CastAway-CTD software version 1.3 (firmware version v026_r2818) was used for data acquisition and processing using default correction algorithms and binned over 0.3 decibar changes. For more information on data processing please see manual at: https://www.sontek.com/castaway-ctd (not open source).

The CTD data report contains some gaps in the temperature, salinity and density data. These gaps result from the removal of outliers.

BCO-DMO Processing Notes:
* Added ISO_DateTime_UTC and ISO_DateTime_PDT columns (ISO formatted DateTimes) by merging the provided date and times of the specific time zones.

More information about this dataset deployment

Funding

Award Number	Funding Source
OCE-2053719	NSF Division of Ocean Sciences

Instruments

Bongo Net

Supplied Name:

Supplied Description:

Instrument Type

Generic Name: Bongo Net

Community Identifier: http://vocab.nerc.ac.uk/collection/L22/current/NETT0009/

Generic Description:

A Bongo Net consists of paired plankton nets, typically with a 60 cm diameter mouth opening and varying mesh sizes, 10 to 1000 micron. The Bongo Frame was designed by the National Marine Fisheries Service for use in the MARMAP program. It consists of two cylindrical collars connected with a yoke so that replicate samples are collected at the same time. Variations in models are designed for either vertical hauls (OI-2500 = NMFS Pairovet-Style, MARMAP Bongo, CalVET) or both oblique and vertical hauls (Aquatic Research). The OI-1200 has an opening and closing mechanism that allows discrete "known-depth" sampling. This model is large enough to filter water at the rate of 47.5 m3/minute when towing at a speed of two knots. More information: Ocean Instruments, Aquatic Research, Sea-Gear

SonTek CastAway-CTD

Supplied Name: SonTek CastAway-CTD model CC1403002

Supplied Description:

Instrument Type

Generic Name: SonTek CastAway-CTD

Acronym: CastAway-CTD

Generic Description:

The Sontek CastAway-CTD (manufactured by Xylem) is a handheld castable instrument that provides instantaneous profiles of temperature, salinity, and sound speed. Each cast is referenced with both time and location using its built-in GPS receiver. The CastAway software displays profiles of the casts in addition to mapping the locations of the data collection points. The CastAway-CTD has a 5 Hz response and sampling rate, accurate to 0.1 (PSS-78), 0.05° Celsius.

Conductivity range is 0 to 100,000 µS/cm.
Temperature range is -5° to 45° Celsius.
Pressure range is 0 to 100 decibars.

Further specs and information can be found on the manufacturer's website: https://www.xylem.com/en-us/brands/wtw/wtw-products/castaway-ctd/

Parameters

Supplied Name	Supplied description	Supplied Units	Standard Name
Cruise	Cruise identifier	unitless	cruiseid
Date_UTC	Sampling date in UTC	unitless	date
Time_UTC	Sampling time in UTC	unitless	time
Date_PDT	Sampling date in PDT (local)	unitless	date
Time_PDT	Sampling time in PDT (local)	unitless	time
Line	CalCOFI line	unitless	station
St	CalCOFI station	unitless	station
Lat	Latitude	decimal degrees	lat
Long	Longitude	decimal degrees	lon
Pres	Water pressure	decibar	press
Depth	Water depth	meters	depth
Temp	Water temperature	degrees Celsius	temp
Sal	Water salinity	practical salinity scale	sal
Dens	Water density	kilograms per cubic meter	density
ISO_DateTime_UTC	Sampling date and time (UTC) in ISO 8601 format yyyy-mm-ddTHH:MM:SSZ	unitless	ISO_DateTime_UTC
ISO_DateTime_PDT	Sampling date and time (PDT, Pacific Daylight Time) in ISO 8601 format yyyy-mm-ddTHH:MM:SS	unitless	ISO_DateTime_Local

Database

Contribute Data

Dataset: CTD data from Bongo plankton net tows
Deployment: BBB2102

Dataset acquisition description

Dataset Processing Description

Database

Contribute Data

Dataset: CTD data from Bongo plankton net towsDeployment: BBB2102

Dataset acquisition description

Dataset Processing Description

Dataset: CTD data from Bongo plankton net tows
Deployment: BBB2102