Abstract:

During the LAgrangian Submesoscale ExpeRiment (LASER), more than 1000 biodegradable drifters were launched in the Gulf of Mexico, in order to study surface flows in winter conditions. The floater, extending 5 cm below the surface, contained the satellite tracking system. The drogue, extending 60 cm below the surface, hung beneath the floater on a flexible tether. On some floats, the drogue separated from the floater during storms. An algorithm was developed to detect drogue loss based on two properties that distinguish drogued from undrogued drifters. First, undrogued drifters often flip over, pointing their satellite antenna downward and thus intermittently reducing the frequency of GPS fixes. Second, undrogued drifters respond more strongly to wind forcing than drogued drifters. 40% of the drifters were found to have lost their drogues in the first 7 weeks between January 20, 2016 and March 29, 2016. Drogue loss times were estimated with a precision of less than a half-hour for 60% of the drifters and less than 3 hrs for 85%. The data set contains the drogue status and drogue-loss estimates of all drifters released during LASER, including the precision and uncertainty levels, as well as the drogue loss estimates from GPS transmission anomalies only. Raw drifter data can be found in GRIIDC dataset R4.x265.000:0027.

Suggested Citation:

A. C. Haza, E. D'Asaro, H. Chang, S. Chen, M. Curcic, C. Guigand, H. S. Huntley, G. Jacobs, G. Novelli, T. M. Ozgokmen, A. C. Poje, E. Ryan, A. Shcherbina. 2017. Drogue status of the Lagrangian Submesoscale Experiment (LASER) surface drifters. Distributed by: GRIIDC, Harte Research Institute, Texas A&M University–Corpus Christi. doi:10.7266/N7QN656H

Publications:

Haza, A. C., D’Asaro, E., Chang, H., Chen, S., Curcic, M., Guigand, C., … Shcherbina, A. (2018). Drogue-Loss Detection for Surface Drifters during the Lagrangian Submesoscale Experiment (LASER). Journal of Atmospheric and Oceanic Technology, 35(4), 705–725. doi:10.1175/jtech-d-17-0143.1

Lodise, J., Özgökmen, T., Griffa, A., & Berta, M. (2019). Vertical structure of ocean surface currents under high winds from massive arrays of drifters. Ocean Science, 15(6), 1627–1651. doi:10.5194/os-15-1627-2019

Jacobs, G. A., D’Addezio, J. M., Bartels, B., & Spence, P. L. (2019). Constrained scales in ocean forecasting. Advances in Space Research. doi:10.1016/j.asr.2019.09.018

Lodise, J., Özgökmen, T., Gonçalves, R. C., Iskandarani, M., Lund, B., Horstmann, J., … Guigand, C. (2020). Investigating the Formation of Submesoscale Structures along Mesoscale Fronts and Estimating Kinematic Quantities Using Lagrangian Drifters. Fluids, 5(3), 159. doi:10.3390/fluids5030159

Haza, A. C., Paldor, N., Özgökmen, T. M., Curcic, M., Chen, S. S., & Jacobs, G. (2019). Wind‐Based Estimations of Ocean Surface Currents From Massive Clusters of Drifters in the Gulf of Mexico. Journal of Geophysical Research: Oceans, 124(8), 5844–5869. doi:10.1029/2018jc014813

Purpose:

The CARTHE drogued drifter follows the averaged Lagrangian velocity of the upper 60 cm. Without a drogue, it follows the upper 5 cm flow only. Laboratory tests indicate that the slip velocity is 0.5% and 2% of the 10m wind speed for the drogued and undrogued drifters, respectively. Accurate estimation of drifter dispersion thus clearly requires that the drogue status of each drifter be known throughout the experiment.

Data Parameters and Units:

Drifter ID, drogue-loss date precision level (1 = within 30 mins, 2 = within 3 hours, 3 = >3 hours, 0 = no drogue-loss detected), drogue-loss date (in Year Day of 2016), drogued drifter uncertainty date (Year Day of 2016, zero if not drogued), drogued drifter uncertainty level (1=likely drogued, 2=likely undrogued, 3=unknown, 0 = undrogued status), GPS transmission anomaly date (days since 2016-01-01)

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