Data Access Options
Project
Hawaii Spray Glider Observations
Date Range
2009-04-09 to 2009-08-20
Sensors
This file contains data from the following specific instruments: Sea-Bird SBE 41CP CTD, Seapoint chlorophyll fluorometer.
Summary
Spray glider data from mission 09402601, part of the Hawaii spray glider observations project. This is the complete science-quality dataset for the full mission, spanning from 2009-04-09 to 2009-08-20.
The overarching goal of this project was sustained sampling of upper ocean hydrography to resolve the seasonal-to-interannual modulation of meso- and fine-scale thermohaline structure. To achieve this goal, Spray underwater gliders made repeated occupations of a 1300-km meridional section northward from Hawaii to 34.5N along 158W. The data set includes 1014 glider-days, covering 22566 km over ground, 22720 km through water, with 4641 dives.
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. Additionally, 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.
An underwater glider runs on batteries and can stay out to sea for months at a time. Spray gliders collect observations on the ascent of a dive. Sensor observations are not collected on the descent and one vertical profile of observations is collected on the ascent of each dive.
Contributors
Daniel Rudnick (PrincipalInvestigator), Instrument Development Group (processor), Jennifer Sevadjian (resourceProvider)
References
Rudnick, D. L. (2016). Ocean research enabled by underwater gliders. Annual review of marine science, 8, 519-541, doi:10.1146/annurev-marine-122414-033913; Rudnick, D. L., Davis, R. E., & Sherman, J. T. (2016). Spray Underwater Glider Operations. Journal of Atmospheric and Oceanic Technology, 33(6), 1113-1122, doi:10.1175/JTECH-D-15-0252.1; Rudnick, D. L., Davis, R. E., Eriksen, C. C., Fratantoni, D. M., & Perry, M. J. (2004). Underwater gliders for ocean research. Marine Technology Society Journal, 38(2), 73-84, doi:10.4031/002533204787522703; Sherman, J., Davis, R. E., Owens, W. B., & Valdes, J. (2001). The autonomous underwater glider 'Spray'. IEEE Journal of oceanic Engineering, 26(4), 437-446, doi:10.1109/48.972076;Rudnick, D. L. and S. T. Cole, 2011: On sampling the ocean using underwater gliders. Journal of Geophysical Research, 116, C08010, doi: 10.1029/2010JC006849; Cole, S. T. and D. L. Rudnick, 2012: The spatial distribution and annual cycle of upper ocean thermohaline structure. Journal of Geophysical Research, 117, C02027, doi: 10.1029/2011JC007033.
Acknowledgement
Funded by the National Science Foundation, grant number OCE0452574.