Oceanography The Official Magazine of
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Volume 28 Issue 01

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Volume 28, No. 1
Pages 96 - 105

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Sea Surface Salinity Observations with Lagrangian Drifters in the Tropical North Atlantic During SPURS: Circulation, Fluxes, and Comparisons with Remotely Sensed Salinity from Aquarius

By Luca R. Centurioni , Verena Hormann, Yi Chao , Gilles Reverdin , Jordi Font, and Dong-Kyu Lee 
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Article Abstract

The Global Drifter Program deployed a total of 144 Lagrangian drifters drogued at 15 m depth, including 88 equipped with salinity sensors, in support of the first Salinity Processes in the Upper-ocean Regional Study (SPURS-1) in the subtropical North Atlantic Ocean with the goal of measuring salt fluxes associated with surface currents. The quality-controlled data set consists of 996,583 salinity observations collected between August 2012 and April 2014. A comparison of the drifter salinities with Aquarius satellite sea surface salinity (SSS) data shows that the lifespan of the salinity sensor fitted to the drifters is of the order of one year. The salinity and velocity data from the drifters were used to validate salt transport divergence computed with satellite products, with satellite salinity taken from the standard Aquarius v3.0 data set. The results indicate good agreement between the two independent methods, and also demonstrate that the effect of the eddy field combined with SSS variability at the surface dominates the signal. SSS variability within spatial bins as compared to Aquarius-beam footprints measured by drifters can be in excess of 0.1 psu. This result suggests that careful evaluation of the representation error is required when single-point in situ measurements, such as those collected by Argo floats, are used to validate spatially averaged Aquarius salinity data.

Citation

Centurioni, L.R., V. Hormann, Y. Chao, G. Reverdin, J. Font, and D.-K. Lee. 2015. Sea surface salinity observations with Lagrangian drifters in the tropical North Atlantic during SPURS: Circulation, fluxes, and comparisons with remotely sensed salinity from Aquarius. Oceanography 28(1):96–105, https://doi.org/10.5670/oceanog.2015.08.

References
    Baturin, N.G., and P.P. Niiler. 1997. Effects of instability waves in the mixed layer of the equatorial Pacific. Journal of Geophysical Research 102(C13):27,771–27,793, https://doi.org/10.1029/97JC02455.
  1. Centurioni, L.R., P.N. Niiler, and D.K. Lee. 2009. Near-surface circulation in the South China Sea during the winter monsoon. Geophysical Research Letters 36, L06605, https://doi.org/10.1029/2008gl037076.
  2. Centurioni, L.R., J.C. Ohlmann, and P.P. Niiler. 2008. Permanent meanders in the California Current System. Journal of Physical Oceanography 38:1,690–1,710, https://doi.org/10.1175/2008JPO3746.1.
  3. Chelton, D.B., M.G. Schlax, R.M. Samelson, and R.A. de Szoeke. 2007. Global observations of large oceanic eddies. Geophysical Research Letters 34, L15606, https://doi.org/10.1029/2007GL030812.
  4. Dessier, A., and J.R. Donguy. 1994. The sea surface salinity in the tropical Atlantic between 10°S and 30°N: Seasonal and interannual variations (1977–1989). Deep Sea Research Part I 41:81–100, https://doi.org/10.1016/0967-0637(94)90027-2.
  5. Ducet, N., P.Y. Le Traon, and G. Reverdin. 2000. Global high-resolution mapping of ocean circulation from TOPEX/Poseidon and ERS-1 and -2. Journal of Geophysical Research 105(C8):19,477–19,498, https://doi.org/10.1029/2000JC900063.
  6. Durack, P.J., and S.E. Wijffels. 2010. Fifty-year trends in global ocean salinities and their relationship to broad-scale warming. Journal of Climate 23:4,342–4,362, https://doi.org/10.1175/2010JCLI3377.1.
  7. Durack, P.J., S.E. Wijffels, and R.J. Matear. 2012. Ocean salinities reveal strong global water cycle intensification during 1950 to 2000. Science 336:455–458, https://doi.org/10.1126/science.1212222.
  8. Font, J., A. Camps, A. Borges, M. Martin-Neira, J. Boutin, N. Reul, Y. H. Kerr, A. Hahne, and S. Mecklenburg. 2010. SMOS: The challenging sea surface salinity measurement from space. Proceedings of the Institute of Electrical and Electronics Engineers 99:649–665, https://doi.org/10.1109/JPROC.2009.2033096.
  9. Gill, A. 1982. Atmosphere-Ocean Dynamics. Elsevier, 662 pp.
  10. Gordon, A.L., and C.F. Giulivi. 2014. Ocean eddy freshwater flux convergence into the North Atlantic subtropics. Journal of Geophysical Research 119:3,327–3,335, https://doi.org/10.1002/2013JC009596.
  11. Hansen, D.V., and P.M. Poulain. 1996. Quality control and interpolations of WOCE-TOGA drifter data. Journal of Atmospheric and Oceanic Technology 13:900–909, https://doi.org/10.1175/1520-0426(1996)013<0900:QCAIOW>2.0.CO;2.
  12. Hormann, V., L.R. Centurioni, and G. Reverdin. 2014. Evaluation of drifter salinities in the subtropical North Atlantic. Journal of Atmospheric and Oceanic Technology 32:185–192, https://doi.org/10.1175/JTECH-D-14-00179.1.
  13. Lagerloef, G., F.R. Colomb, D. Le Vine, F. Wentz, S. Yueh, C. Ruf, J. Lilly, J. Gunn, Y. Chao, A. deCharon, and others. 2008. The Aquarius/Sac-D mission: Designed to meet the salinity remote-sensing challenge. Oceanography 21(1):68–81, https://doi.org/10.5670/oceanog.2008.68.
  14. Lopez, R., J.P. Malarde, F. Royer, and P. Gaspar. 2014. Improving Argos Doppler location using multiple-model Kalman filtering. IEEE Transactions on Geoscience and Remote Sensing 52:4,744–4,755, https://doi.org/10.1109/TGRS.2013.2284293.
  15. Maximenko, N., R. Lumpkin, and L. Centurioni. 2013. Ocean surface circulation. Pp. 283–284 in Ocean Circulation and Climate: A 21st Century Perspective. G. Siedler, S. Griffies, J. Gould, and J. Church, eds, International Geophysics, vol. 103, Academic Press, https://doi.org/10.1016/B978-0-12-391851-2.00012-X.
  16. Maximenko, N., P. Niiler, L. Centurioni, M.-H. Rio, O. Melnichenko, D. Chambers, V. Zlotnicki, and B. Galperin. 2009. Mean dynamic topography of the ocean derived from satellite and drifting buoy data using three different techniques. Journal of Atmospheric and Oceanic Technology 26:1,910–1,919, https://doi.org/10.1175/2009JTECHO672.1.
  17. Moisan, J.R., and P.P. Niiler. 1998. The seasonal heat budget of the North Pacific: Net heat flux and heat storage rates (1950–1990). Journal of Physical Oceanography 28:401–421, https://doi.org/10.1175/1520-0485(1998)028<0401:TSHBOT>2.0.CO;2.
  18. Niiler, P.P. 2001. The world ocean surface circulation. Pp. 193–204 in Ocean Circulation and Climate: A 21st Century Perspective. G. Siedler, J. Church, and J. Gould, eds, Academic Press.
  19. Niiler, P.P., A. Sybrandy, K. Bi, P.M. Poulain, and D. Bitterman. 1995. Measurements of the water-following capability of holey-sock and TRISTAR drifters. Deep-Sea Research Part 1 42:1,951–1,964, https://doi.org/10.1016/0967-0637(95)00076-3.
  20. Pazan, S.E., and P.P. Niiler. 2001. Recovery of near-surface velocity from undrogued drifters. Journal of Atmospheric and Oceanic Technology 18(3):476–489, https://doi.org/10.1175/1520-0426(2001)018<0476:RONSVF>2.0.CO;2.
  21. Reverdin, G., J. Boutin, A. Lourenco, P. Blouch, J. Rolland, P.P. Niiler, W. Scuba, and A.F. Rios. 2007a. Surface salinity measurements: COSMOS 2005 experiment in the Bay of Biscay. Journal of Atmospheric and Oceanic Technology 24:1,643–1,654, https://doi.org/10.1175/JTECH2079.1.
  22. Reverdin, G., E. Kestenare, C. Frankignoul, and T. Delcroix. 2007b. Surface salinity in the Atlantic Ocean (30°S–50°N). Progress In Oceanography 73:311–340, https://doi.org/10.1016/j.pocean.2006.11.004.
  23. Reverdin, G., S. Morisset, J. Boutin, N. Martin, M. Sena-Martins, F. Gaillard, P. Bouch, J. Rolland, J. Font, J. Salvador, and others. 2014. Validation of salinity data from surface drifters. Journal of Atmospheric and Oceanic Technology 31:967–983, https://doi.org/10.1175/JTECH-D-13-00158.1.
  24. Reverdin, G., S. Morisset, L. Marié, D. Bourras, G. Sutherland, B. Ward, J. Salvador, J. Font, Y. Cuypers, L. Centurioni, and others. 2015. Surface salinity in the North Atlantic subtropical gyre during the STRASSE/SPURS summer 2012 cruise. Oceanography 28(1):114–123, https://doi.org/10.5670/oceanog.2015.09.
  25. Schmitt, R.W. 2008. Salinity and the global water cycle. Oceanography 21(1):12–19, https://doi.org/10.5670/oceanog.2008.63.
  26. Schott, F.A., J.P. McCreary, and G.C. Johnson. 2004. Shallow overturning circulations of the tropical-subtropical oceans. Pp. 261–304 in Earth’s Climate. C. Wang, S.P. Xie, and J.A. Carton, eds, American Geophysical Union, Washington, DC.
  27. Snowden, D.P., and R.L. Molinari. 2003. Subtropical cells in the Atlantic Ocean: An observational summary. Pp. 287–312 in Interhemispheric Water Exchange in the Atlantic Ocean. Elsevier Oceanography Series, vol. 68, G.J. Goni and P. Malanotte-Rizzoli, eds, Elsevier, https://doi.org/10.1016/S0422-9894(03)80151-4.
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