Science Quality

Science Quality Full-Resolution Data from Spray Glider Mission 23506901 (sp069-20230507T1437)

Project

SWOT Adopt-A-Crossover - MAB-SWOT


Site

Cape Hatteras


Date Range

2023-05-07 to 2023-06-14


Sensors

This file contains data from the following specific instruments: Sea-Bird SBE 41CP CTD, Seapoint chlorophyll fluorometer.


Summary

Spray glider data from mission 23506901, part of the SWOT Adopt-A-Crossover - MAB-SWOT project. This is the complete science-quality dataset for the full mission, spanning from 2023-05-07 to 2023-06-14.

During the first several months of the Surface Water and Ocean Topography (SWOT) satellite mission, the satellite was in an orbit that passed over select locations twice per day (one ascending and one descending pass). One of these 'cross-overs' was located offshore of Cape Hatteras, NC where the Gulf Stream detaches from the continetal margin. In support of the calibration and validation of the SWOT measurements of sea surface topography, Spray gliders sampled within this cross-over as part of the SWOT Adopt-A-Crossover - MAB-SWOT campaign (https://www.swot-adac.org/campaigns/mab-swot/) in 2023. Gliders primarily attempted to hold station at the center of a triangular array of CPIEs just north of the Gulf Stream. Additional plots of these data are available at https://gliders.whoi.edu.

This is a delayed-mode science-quality data product providing the highest-resolution and highest quality data for this mission. After a glider mission is complete and the glider is recovered, the full-resolution data are downloaded and quality controlled resulting in this data product. This product is typically available three to six months after a glider mission is complete.

The delayed-mode science quality full-resolution data product should be used in place of near-real-time data once this higher-quality data product is available. This is a rigorously quality controlled dataset, the results of quality control tests are included as flags. Where appropriate, in addition to the original data with quality flags, corrected variables are also provided. These are noted in the variable metadata.Users of the data must apply the quality control flag variables referenced as ancillary variables on the data variables, these flags provide necessary information for using the data.

About these measurements: A Spray glider moves slowly through the water and collects information about the water it is traveling through. It collects a series of vertical profiles from the ocean seafloor (up to 1000m deep) to the ocean surface. In typical operations to 1000 m depth, a Spray glider travels 15 miles and makes 4 profiles per day. When on the ocean surface, about every three to six hours, it sends the information it collected underwater back via satellite, and then dives back down to continue collecting data.

The Spray ocean glider carries a pumped Sea-Bird CTD to measure pressure, temperature, and salinity, a Seapoint fluorometer, and a Sea-Bird dissolved oxygen sensor. A Nortek acoustic Doppler current profiler (ADCP) measures depth dependent water velocity. The ocean glider position is measured at the surface at the beginning and end of each dive by GPS, allowing for a dead reckoning estimation of depth averaged water velocity.

Spray gliders collect observations on the ascent of a dive. Sensor observations are not collected on the descent. One vertical profile is collected on the ascent of each dive.


Contributors

Robert Todd (PrincipalInvestigator), Instrument Development Group (processor), Jennifer Sevadjian (resourceProvider)


Acknowledgement

This project has been funded by the National Aeronautics and Space Administration (NASA). Data distribution support is provided by the Instrument Development Group at Scripps Institution of Oceanography.