Metadata Report for BODC Series Reference Number 2026483

• Metadata Summary

• Problem Reports

• Data Access Policy

• Narrative Documents

• Project Information

• Data Activity or Cruise Information

• Fixed Station Information

• BODC Quality Flags

• SeaDataNet Quality Flags

Metadata Summary

Problem Reports

No Problem Report Found in the Database

Data Access Policy

Open Data

These data have no specific confidentiality restrictions for users. However, users must acknowledge data sources as it is not ethical to publish data without proper attribution. Any publication or other output resulting from usage of the data should include an acknowledgment.

If the Information Provider does not provide a specific attribution statement, or if you are using Information from several Information Providers and multiple attributions are not practical in your product or application, you may consider using the following:

"Contains public sector information licensed under the Open Government Licence v1.0."

Narrative Documents

RD Instruments- Ocean Surveyor 150kHz Vessel mounted ADCP.

¹ Ranges at 1 to 5 knots ship speed are typical and vary with situation.
² Single-ping standard deviation.
³ User's choice of depth cell size is not limited to the typical values specified.

Profile Parameters

• Velocity long-term accuracy (typical): ±1.0%, ±0.5cm/s
• Velocity range: -5 to 9m/s
• # of depth cells: 1 - 128
• Max ping rate: 1.5

Bottom Track

Maximum altitude (precision <2cm/s): 600m

Echo Intensity Profile

Dynamic range: 80dB
Precision: ±1.5dB

Transducer & Hardware

Beam angle: 30°
Configuration: 4-beam phased array
Communications: RS-232 or RS-422 hex-ASCII or binary output at 1200 - 115,200 baud
Output power: 1000W

Standard Sensors

Temperature (mounted on transducer)

• Range: -5° to 45°C
• Precision: ±0.1°C
• Resolution: 0.03°

Environmental

Operating temperature: -5° to 40°C (-5° to 45°C)*
Storage temperature: -30° to 50°C (-30° to 60°C)*

*later instruments have greater range.

Web Page

Further details can be found in the manufacturer's website or in the specification sheet.

CLASS cruise JC191 BODC Vessel Mounted ADCP data processing

The data arrived at BODC in two mstar (NetCDF subset) format files containing data collected from the 75kHz and 150kHz ship mounted ADCPs during cruise JC191. The data were reformatted to BODC's internal NetCDF format. The following table shows the mapping of variables within the mstar files to appropriate BODC parameter codes:

The reformatted data were visualised using the in-house EDSERPLO software. Suspect data were marked by adding an appropriate quality control flag, and missing data were set to an appropriate value and flagged. Deeper bins (>781 m) for the 75 kHz dataset and (>369 m) for the 150 kHz dataset contain no current speed estimates.

CLASS cruise JC191 Originator's Vessel Mounted ADCP data processing

The following was taken from the JC191 cruise report. Data were collected using a Teledyne RDI Ocean Surveyor 75 kHz vessel mounted ADCP and a Teledyne RDI Ocean Surveyor 150 kHz vessel mounted ADCP. The instruments were set to sample throughout the cruise, from the coast of Florida, USA to Tenerife, Canary Islands. For more detailed information please refer to Sanchez-Franks (2020).

Data were acquired using the UHDAS software package.

ADCP setup

Both instruments were run in bottom tracking mode until 2020/01/23 15:17 UTC, and then switched to water tracking mode. They were set to ping in self triggered mode.

Real time data acquisition and monitoring

Data acquisition and processing were handled by UHDAS (University of Hawaii Data Acquisition System). This software handles both acquisition and CODAS (common ocean data access sytem) first pass processing. Data was collected continuously and a new file was written every 100,000 cycles. On 2020/01/21 at 12:38 UTC data collection was stopped and restarted whilst the two adcps were switched to the correct computer inputs.

First pass processing

UHDAS automates the removal of ship velocity, heading correction with GPS derived heading, calibration to estimate heading misalignment using "bottom track" or "water track" data.

Post-processing

Manual inspection and removal of bad data using the dataviewer.py application. Data were flagged as bad if below the bottom, below a threshold or manually.

Output files

Once the UHDAS processing had been completed, the final velocities were collated into mstar files (a NetCDF subset). The files contained time, latitude, longitude, depth, absolute eastward current speed, absolute northward current speed, eastward ship speed, northward ship speed, days, scalar current speed, and scalar ship speed.

References

Sanchez-Franks, A.2020. RRS James Cook Cruise JC191, 19 January - 1 March 2020. Hydrographic sections from the Florida Straits to the Canaries Current across 24°N in the Atlantic Ocean. Southampton, UK: National Oceanography Centre, Southampton, 262pp., National Oceanography Centre Cruise Report, No. 70.

Project Information

Marine LTSS: CLASS (Climate Linked Atlantic Sector Science)

Introduction

CLASS is a five year (2018 to 2023) programme, funded by the Natural Environment Research Council (NERC) and extended until March 2024.

Scientific Rationale

The ocean plays a vital role in sustaining life on planet Earth, providing us with both living resources and climate regulation. The trajectory of anthropogenically driven climate change will be substantially controlled by the ocean due to its absorption of excess heat and carbon from the atmosphere, with consequent impacts on ocean resources that remain poorly understood. In an era of rapid planetary change, expanding global population and intense resource exploitation, it is vital that there are internationally coordinated ocean observing and prediction systems so policy makers can make sound evidence-based decisions about how to manage our interaction with the ocean. CLASS will underpin the UK contribution to these systems, documenting and understanding change in the marine environment, evaluating the impact of climate change and effectiveness of conservation measures and predicting the future evolution of marine environments. Over the five-year period CLASS will enhance the cost-effectiveness of observing systems by migrating them towards cutting edge autonomous technologies and developing new sensors. Finally, CLASS will create effective engagement activities ensuring academic partners have transparent access to NERC marine science capability through graduate training partnerships and access to shipborne, lab based and autonomous facilities, and modelling capabilities.

Data Activity or Cruise Information

Cruise

Complete Cruise Metadata Report is available here

Fixed Station Information

Fixed Station Information

24.5 degrees N Hydrographic Transatlantic section - A05

The hydrographic transatlantic section at 24.5 degrees North has been occupied 8 times, namely in 1957, 1981, 1992, 1998, 2004, 2010, 2015 and 2020. The section is an attempt to calculate the transports of water and its constituents (heat, salinity, nutrients, biological productivity) along this latitude, and to compare the data so that the degree of change in the North Atlantic transports can be revealed. The Hydrographic Programme of the international World Ocean Circulation Experiment (WOCE) designated this section as A05. Since WOCE, the section occupations contribute to the Global Ocean Ship-Based Hydrographic Investigations Program (GO-SHIP).

Map of stations

The station positions for most of the occupied sections are shown in the above figures. Sections occupied in 1957, 1981, 1992, 1998 and 2004 are shown in the upper figure. The section occupied in 2010 is shown in the lower figure.

The 1957 and 1992 sections each went zonally along 24.5 degrees N from the African coast to the Bahama Islands. Because of diplomatic clearance issues, the 1981, 1998, 2004, 2010 and 2015 sections angled southwestward from the African coast at about 28 degrees N to join the 24.5 degrees N section at about 23 degrees W. The 1998, 2004 and 2010 sections angled northwestward at about 73 degrees W to finish the section along 26.5 degrees N. The 2010 and 2020 sections deviated from the previous sections across the Mid-Atlantic Ridge (MAR) in order to sample the deepest channel and capture the passage of the deep water across the MAR.

Table 1: Occupations of the section

References

Baringer, M. O. N. and R. L. Molinari, 1999. Atlantic Ocean baroclinic heat flux at 24 to 26°N. Geophysical Research Letters, 26, 353-356.

Bryden, H. L., H. R. Longworth, and S. Cunningham, 2005b. Slowing of the Atlantic meridional overturning circulation at 25°N. Nature, 438, 655-657.

Fuglister, F. C., 1960. Atlantic Ocean Atlas of Temperature and Salinity Profiles and Data from the International Geophysical Year of 1957-1958. Vol. 1, Woods Hole Oceanographic Institution Atlas Series, WHOI, Woods Hole, Massachusetts.

King, B. A. et al., 2012. RRS Discovery Cruise 346, 05 Jan-19 Feb 2010. The 2010 transatlantic hydrography section at 24.5N. Southampton, UK, National Oceanography Centre Southampton, 177pp. (National Oceanography Centre Cruise Report, No. 16).

King, B. A. et al., 2016. RRS Discovery Cruise DY040 (RAGNARoCC), 06 Dec 2015 - 22 Jan 2016. The 2015 transatlantic hydrography section at 24.5N. Southampton, UK, National Oceanography Centre Southampton, 159pp. (National Oceanography Centre Cruise Report).

Parilla, G., A.Lavin, H. Bryden, M. Garcia, and R. Millard, 1994. Rising temperatures in the subtropical North Atlantic Ocean over the past 35 years. Nature, 369, 48-51.

Roemmich, D. and C. Wunsch, 1985. Two transatlantic sections: meridional circulation and heat flux in the subtropical North Atlantic Ocean. Deep Sea Research, 32, 619-664.

Sanchez-Franks, A., 2020. RRS James Cook Cruise JC191, 19 January - 1 March 2020. Hydrographic sections from the Florida Straits to the Canaries Current across 24N in the Atlantic Ocean. Southampton, UK, National Oceanography Centre Southampton, 262pp. (National Oceanography Centre Cruise Report, No. 70).

Related Fixed Station activities are detailed in Appendix 1

BODC Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

SeaDataNet Quality Control Flags

The following single character qualifying flags may be associated with one or more individual parameters with a data cycle:

Appendix 1: 24.5 degrees N Hydrographic Transatlantic section - A05

Related series for this Fixed Station are presented in the table below. Further information can be found by following the appropriate links.

If you are interested in these series, please be aware we offer a multiple file download service. Should your credentials be insufficient for automatic download, the service also offers a referral to our Enquiries Officer who may be able to negotiate access.