Abstract:

Several hundred Consortium for Advanced Research on Transport of Hydrocarbon in the Environment (CARTHE) surface drifters were released during the Submesoscale Processes and Lagrangian Analysis on the Shelf (SPLASH) experiment in the Louisiana Bight from 2017-04-19 to 2017-09-18. The drifters were drogued at 0.5 m depth and reported their positions in real-time using SPOT GPS units nominally every 5 minutes for up to about 5 months. Some of the drifters were equipped with temperature and/or salinity sensors. This dataset contains the raw data, except for duplicate entries, out-of-range positions, and data before launch have been eliminated. This dataset was created by the CARTHE. This research was made possible by a grant from the Gulf of Mexico Research Initiative. A companion dataset with cleaned and interpolated trajectories is available under GRIIDC Unique Dataset Identifiers (UDI) R4.x265.000:0074 (DOI: 10.7266/n7-0pkg-hd54).

Suggested Citation:

Daniel Carlson, Cedric Guigand, Brian Haus, Angelique Haza, Helga Huntley, Nathan Laxague, Jamie MacMahan, Philippe Miron, Jeroen Molemaker, Guillaume Novelli, Tamay Özgökmen, Ed Ryan, Andrey Shcherbina, Aviv Solodov, Alex Soloviev, Arnoldo Valle-Levinson. 2019. Submesoscale Processes and Lagrangian Analysis on the Shelf (SPLASH) surface drifter’s raw data in the Louisiana Bight from 2017-04-19 to 2017-09-18. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/n7-wgt0-kw56

Publications:

Lund, B., Haus, B. K., Graber, H. C., Horstmann, J., Carrasco, R., Novelli, G., … Özgökmen, T. M. (2020). Marine X‐Band Radar Currents and Bathymetry: An Argument for a Wave Number‐Dependent Retrieval Method. Journal of Geophysical Research: Oceans, 125(2). doi:10.1029/2019jc015618

Solodoch, A., Molemaker, J. M., Srinivasan, K., Berta, M., Marie, L., & Jagannathan, A. (2020). Observations of Shoaling Density Current Regime Changes in Internal Wave Interactions. Journal of Physical Oceanography, 50(6), 1733–1751. doi:10.1175/jpo-d-19-0176.1

Purpose:

The drifters were released to study submesoscale dispersion on the shelf.

Data Parameters and Units:

SPLASH_drifters_raw.dat: ID (drifter id), Date/time (yyyy-mm-dd HH:MM, UTC), Longitude and latitude (decimal degrees). Splash_spot_drifter_launch_info.prn: The launch coordinates and times were recorded with a hand-held GPS device at the time of launch and some of the coordinates may be missing. Drifter id, drifter type (drogued= standard drifters, undrogued = standard drifters but without drogue, temperature = standard drifters with temperature (HOBO) sensor, salinity= standard drifters with temperature + salinity (HOBO) sensors), launch date/time (yyyy-mm-dd HH:MM:SS, UTC), vessel (WS for Walton Smith; the others are small boats ARGUS, Alex, Arnoldo, CB for Calibou Boca, SAND_CRAB, TATIANA, UCLA, and WHISKEY_PASS), launch group (see ReadMe file), launch node (see ReadMe file), Longitude and latitude (decimal degrees), end date and time of the entire record deemed credible (yyyy-mm-dd HH:MM:SS). HOBO instruments: Date/time (mm/dd/yyyy hh:mm), temperature (C), conductivity (micro S/cm) and sensor information. Note that there are multiple time zones among HOBO files. Please refer to the file header to confirm. There is also a ‘KDS’ folder, which contains contemporaneous data from the UCLA Zodiac’surface sampler. Each KDS filename contains the sampling date and time. For a description of their content, see the ‘KDS_Files_Notes.txt’ file in this folder. Calibration files have been included in the dataset.

Methods:

The CARTHE-style drifters (drogued at 0.5 m), tracked in real-time using SPOT GPS units, were released in multiple groups, including several survey lines and multiple gridded arrays with various spacing, in the Louisiana Bight of the northern Gulf of Mexico in April-May 2017. Some of the drifters had temperature and salinity sensors attached. Many drifters (including those with sensors) were released and recaptured for repeated releases. Minimal quality control was performed on the data, removing duplicate entries, out of range positions, and data before the launch time.

Instruments:

CARTHE drifters were developed for the LASER experiment in 2016 and are commercially available from Pacific Gyre. They are low-coast, almost entirely biodegradable, and reliable.

Individual Files: