Empirical Models of the Loop Current Eddy Detachment/Separation Time in the Gulf of Mexico
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 140, Issue 3
Abstract
Eddies pinching off the Loop Current can have a significant impact on offshore exploration and production activities in the Gulf of Mexico. Advance knowledge of an eddy shedding event would be of considerable value to the offshore industry and coastal and ocean engineering community that serves the offshore industry. However, imperfect understanding of the dynamics of the Loop Current eddy pinch-off has made reliable forecasting of such events elusive. Two empirical, phenomenological models are presented of the Loop Current eddy detachment/separation times based on the retreat latitude of the Loop Current and its rate of intrusion prior to eddy shedding, and the volume flow rate of the outflow in the Yucatan Channel. The models do a fairly good job of hindcasting past separation and detachment events for which observational data are available. The models also showed some skill when applied to forecasting the detachment of eddy Franklin in early June 2010, which occurred not long after the Deepwater Horizon rig explosion. However, because of the inherent limitations of the observational database available and used (e.g., its less than ideal temporal coverage and interpretational errors) and the very complexity of the eddy shedding process, the author cautions that the methodology is by no means conclusively proven. However, it is one worth continuing to explore as more and more increasingly accurate data and steadily improving understanding of the underlying physics become available in the coming decades.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The author thanks Nick Hoffman and Bob Leben of CCAR for providing updated LC statistics and data in Table 2, which helped conclude this study. He also thanks all the reviewers for their excellent suggestions, which have improved this paper significantly. He thanks Reviewer No. 5, in particular, for bringing to the author’s attention the paper by Vukovich (2012), which included important findings on recent changes in LCE shedding.
References
Bunge, L., Ochoa, J., Badan, A., Candela, J., and Sheinbaum, J. (2002). “Deep flows in the Yucatan Channel and their relation to changes in the Loop Current extension.” J. Geophys. Res., 107(C12), 26-1–26-7.
Capurro, L. R. A., and Reid J. L., Jr., eds. (1972). Contributions on the physical oceanography of the Gulf of Mexico, Gulf Publishing, Houston.
Elliot, B. A. (1982). “Anticyclonic rings in the Gulf of Mexico.” J. Phys. Oceanogr., 12(11), 1291–1309.
Forristal, G., Leben, R., and Hall, C. (2010). “A statistical hindcast and forecast model for the Loop Current.” Proc., Offshore Technology Conf., Society of Petroleum Engineers, Dallas.
Hurlburt, H. E., and Thompson, J. D. (1980). “A numerical study of Loop Current intrusions and eddy shedding.” J. Phys. Oceanogr., 10(10), 1611–1651.
Kantha, L., Choi, J.-K., Schaudt, K. J., and Cooper, C. K. (2005). “A regional data assimilative model for operational use in the Gulf of Mexico.” Circulation in the Gulf of Mexico: Observations and models, W. Sturges and A. Lugo-Fernandez, eds., American Geophysical Union, Washington, DC, 165–180.
Kantha, L. H., et al. (1999). “Hindcasts and real-time nowcast/forecasts of currents in the Gulf of Mexico.” Proc., Offshore Technology Conf., Society of Petroleum Engineers, Dallas.
Leben, R. R. (2005). “Altimeter-derived Loop Current metrics.” Circulation in the Gulf of Mexico: Observations and models, W. Sturges and A. Lugo-Fernandez, eds., American Geophysical Union, Washington, DC, 181–202.
Leben, R. R., and Born, G. H. (1993). “Tracking Loop Current eddies with satellite altimetry.” Adv. Space Res., 13(11), 325–333.
Lugo-Fernandez, A., and Badan, A. (2007). “On the vorticity cycle of the Loop Current.” J. Mar. Res., 65(4), 471–489.
Lugo-Fernandez, A., and Leben, R. (2010). “On the linear relationship between the Loop Current retreat latitude and eddy separation.” J. Phys. Oceanogr., 40(12), 2778–2784.
Maul, G. A. (1977). “The annual cycle of the Loop Current, Part 1: Observations during a one-year time series.” J. Mar. Res., 35(1), 49–74.
Maul, G. A., Mayer, D. A., and Baig, S. R. (1985). “Comparison between a continuous three-year current meter observation at the sill of the Yucatan Strait, satellite measurements of the Gulf Loop Current area, and regional sea level.” J. Geophys. Res., 90(C5), 9089–9096.
Oey, L.-Y., et al. (2005a). “An exercise in forecasting Loop Current and eddy frontal positions in the Gulf of Mexico.” Geophys. Res. Lett., 32(12), L12611.
Oey, L.-Y., Ezer, T., and Lee, H.-C. (2005b). “Loop Current rings and related circulation in the Gulf of Mexico: A review of numerical models and future challenges.” Circulation in the Gulf of Mexico: Observations and models, W. Sturges and A. Lugo-Fernandez, eds., American Geophysical Union, Washington, DC, 31–56.
Schaudt, K. J., et al. (2001). “A look at currents in the Gulf of Mexico in 1999–2000.” Proc., Offshore Technology Conf., Society of Petroleum Engineers, Dallas.
Schmitz, W. J., Jr., Biggs, D. C., Lugo-Fernandez, A., Oey, L.-Y., and Sturges, W. (2005). “A synopsis of the circulation in the Gulf of Mexico and on its continental margins.” Circulation in the Gulf of Mexico: Observations and models, W. Sturges and A. Lugo-Fernandez, eds., American Geophysical Union, Washington, DC, 11–30.
Sheinbaum, J., Candela, J., Badan, A., and Ochoa, J. (2002). “Flow structure and transport in Yucatan Channel.” Geophys. Res. Lett., 29(3), 10-1–10-4.
Sturges, W. (1994). “The frequency of ring separations from the loop current.” J. Phys. Oceanogr., 24(7), 1647–1651.
Sturges, W., Hoffman, N., and Leben, R. (2010). “A trigger mechanism for Loop Current ring separations.” J. Phys. Oceanogr., 40(5), 900–913.
Sturges, W., and Leben, R. (2000). “Frequency of ring separations from the Loop Current in the Gulf of Mexico: A revised estimate.” J. Phys. Oceanogr., 30(7), 1814–1819.
Sturges, W., and Lugo-Fernandez, A., eds. (2005). Circulation in the Gulf of Mexico: Observations and models, American Geophysical Union, Washington, DC.
U.S. Energy Information Administration. (2013). “Gulf of Mexico fact sheet.” 〈http://www.eia.gov/special/gulf_of_mexico/〉 (Jun. 26, 2013).
Vukovich, F. M. (1988). “Loop Current boundary variations.” J. Geophys. Res., 93(C12), 15585–15591.
Vukovich, F. M. (1995). “An updated evaluation of the Loop Current’s eddy shedding frequency.” J. Geophys. Res., 100(C5), 8655–8659.
Vukovich, F. M. (2007). “Climatology of ocean features in the Gulf of Mexico using satellite remote sensing data.” J. Phys. Oceanogr., 37(3), 689–707.
Vukovich, F. M. (2012). “Changes in the Loop Current’s eddy shedding in the period 2001-2010.” Int. J. Oceanogr., 2012(2012), 439042.
Information & Authors
Information
Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 140 • Issue 3 • May 2014
Copyright
© 2014 American Society of Civil Engineers.
History
Received: Sep 18, 2012
Accepted: Jun 26, 2013
Published online: Jun 28, 2013
Published in print: May 1, 2014
Discussion open until: Jul 12, 2014
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.