Journal of Ocean University of China

, Volume 12, Issue 2, pp 230–236 | Cite as

The impact of meso-scale eddies on the Subtropical Mode Water in the western North Pacific



Based on the temperature and salinity from the Argo profiling floats and altimeter-derived geostrophic velocity anomaly (GVA) data in the western North Pacific during 2002–2011, the North Pacific Subtropical Mode Water (NPSTMW) distribution is investigated and cyclonic and anti-cyclonic eddies (CEs and AEs) are constructed to study the influence of their vertical structures on maintaining NPSTMW. Combining eddies identified by the GVA data and Argo profiling float data, it is found that the average NPSTMW thickness of AEs is about 60 dbar, which is thicker than that of CEs. The NPSTMW thicker than 150 dbar in AEs accounts for 18%, whereas that in CEs accounts for only 1%. About 3377 (3517) profiles, which located within one diameter of the nearest CEs (AEs) are used to construct the CE (AE). The composite AE traps low-PV water in the center and with a convex shape in the vertical section. The ‘trapped depth’ of the composite CE (AE) is 300 m (550 m) where the rotational velocity exceeds the transitional velocity. The present study suggests that the anticyclonic eddies are not only likely to form larger amounts of NPSTMW, but also trap more NPSTMW than cyclonic eddies.

Key words

thickness of NPSTMW meso-scale eddies swirl velocity trapped depth 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Akima, H., 1970. A new method of interpolation and smooth curve fitting based on local procedures. Journal of the Association for Computing Machinery, 17: 589–603.CrossRefGoogle Scholar
  2. Bingham, F. M., 1992. Formation and spreading of subtropical mode water in the North Pacific. Journal Geophysical Research, 97: 11177–11189.CrossRefGoogle Scholar
  3. Böhme, L., and Send, U., 2005. Objective analyses of hydrographic data for referencing profiling float salinities in highly variable environments. Deep Sea Research Part II, 52: 651–664.CrossRefGoogle Scholar
  4. Chaigneau, A., Le Texier, M., Eldin, G., Grados, C., and Pizarro, C., 2011. Vertical structure of mesoscale eddies in the eastern South Pacific Ocean: A composite analysis from altimetry and Argo profiling floats. Journal Geophysical Research, 116, C11025, DOI: 10.1029/2011JC007134.CrossRefGoogle Scholar
  5. Chelton, D. B., Schlax, M. G., and Samelson, R. M., 2011. Global observations of nonlinear mesoscale eddies. Progress in Oceanography, 91: 167–216.CrossRefGoogle Scholar
  6. Chelton, D. B., Schlax, M. G., Samelson, R. M., and de Szoeke, R. A., 2007. Global observations of large oceanic eddies. Geophysical Research Letters, 34, L15606, DOI: 10.1029/ 2007GL030812.CrossRefGoogle Scholar
  7. Cressman, G. P., 1959. An operational objective analysis system. Monthly Weather Review, 87: 367–374.CrossRefGoogle Scholar
  8. Flierl, G. R., 1981. Particle motions in large-amplitude wave fields. Geophysical Journal of the Royal Astronomical Society, 18: 39–74.Google Scholar
  9. Ishii, M., and Kimoto, M., 2009. Reevaluation of historical ocean heat content variations with time-varying XBT and MBT depth bias corrections. Journal of Oceanography, 65(3): 287–299.CrossRefGoogle Scholar
  10. Ishii, M., Shouji, A., Sugimoto, S., and Matsumoto, T., 2005. Objective analyses of SST and marine meteorological variables for the 20th century using COADS and the Kobe Collection. International Journal of Climatology, 25(7): 865–879.CrossRefGoogle Scholar
  11. Kouketsu, S., Tomita, H., Oka, E., Hosoda, S., Kobayashi, T., and Sato, K., 2012. The role of meso-scale eddies in mixed layer deepening and mode water formation in the western North Pacific. Journal of Oceanography, 68: 63–77.CrossRefGoogle Scholar
  12. Le Traon, P. Y., and Dibarboure, G., 1999. Mesoscale mapping capabilities from multiple altimeter missions. Journal of Atmospheric & Oceanic Technology, 16: 1208–1223.CrossRefGoogle Scholar
  13. Masuzawa, J., 1969. Subtropical mode water. Deep Sea Research, 16: 463–472.Google Scholar
  14. Nencioli, F., Dong, C., Dickey, T., Washburn, L., and McWilliams, J., 2010. A vector geometry based eddy detection algorithm and its application to high-resolution numerical model products and High-Frequency radar surface velocities in the Southern California Bight. Journal of Atmospheric & Oceanic Technology, 27(3): 564–579.CrossRefGoogle Scholar
  15. Nishikawa, S., Tsujino, H., Sakamoto, K., and Nakano, H., 2010. Effects of mesoscale eddies on subduction and distribution of subtropical mode water in an eddy-resolving OGCM of the western North Pacific. Journal of Physical Oceanography, 40: 1748–1765.CrossRefGoogle Scholar
  16. Oka, E., Suga, T., Sukigara, C., Toyama, K., Shimada, K., and Yoshida, J., 2011. ‘Eddy-resolving’ observation of the North Pacific subtropical mode water. Journal of Physical Oceanography, 41: 666–681.CrossRefGoogle Scholar
  17. Owens, W. B., and Wong, A. P. S., 2009. An improved calibration method for the drift of the conductivity sensor on autonomous CTD profiling floats by θ-S climatology. Deep Sea Research Part I, 56: 450–457.CrossRefGoogle Scholar
  18. Pascual, A., Faugère, Y., Larnicol, G., and Le Traon, P. Y., 2006. Improved description of the ocean mesoscale variability by combining four satellite altimeters. Geophysical Resserch Letters, 33, L02611, DOI: 10.1029/2005GL024633.CrossRefGoogle Scholar
  19. Qiu, B., and Chen, S., 2006. Decadal variability in the formation of the North Pacific subtropical mode water: Oceanic versus atmospheric control. Journal of Physical Oceanography, 36: 1365–1380.CrossRefGoogle Scholar
  20. Qiu, B, Hacker, P., Chen, S., Donohue, K. A., Watts, D. R., Mitsudera, H., Hogg, N. G., and Jayne, S. R., 2006. Observations of the subtropical mode water evolution from the Kuroshio Extension System Study. Journal of Physical Oceanography, 36: 457–473.CrossRefGoogle Scholar
  21. Qu, T., Xie, S. P., Mitsudera, H., and Ishida, A., 2002. Subduction of the North Pacific mode waters in a global high-resolution GCM. Journal of Physical Oceanography, 32: 746–763.CrossRefGoogle Scholar
  22. Rainville, L., Jayne, S. R., McClean, J. L., and Maltrud, M. E., 2007. Formation of subtropical mode water in a high-resolution ocean simulation of the Kuroshio Extension region. Ocean Modelling, 17: 338–356.CrossRefGoogle Scholar
  23. Suga, T., and Hanawa, K., 1995. The subtropical mode water circulation in the North Pacific. Journal of Physical Oceanography, 25: 958–970.CrossRefGoogle Scholar
  24. Suga, T., Hanawa, K., and Toba, Y., 1989. Subtropical mode water in the 137°E section. Journal of Physical Oceanography, 19: 1605–1618.CrossRefGoogle Scholar
  25. Suga, T., Motoki, K., Aoki, Y., and Macdonald, A. M., 2004. The North Pacific climatology of winter mixed layer and mode waters. Journal of Physical Oceanography, 34: 3–22.CrossRefGoogle Scholar
  26. Uehara, H., Suga, T., Hanawa, K., and Shikama, N., 2003. A role of eddies in formation and transport of North Pacific Subtropical Mode Water. Geophysical Resserch Letters, 30(13), 1705, DOI: 10.1029/2003GL017542.CrossRefGoogle Scholar
  27. van Aken, H., van Veldhoven, A. K., Veth, C., de Ruijter, W. P. M., van Leeuwen, P. J., Drijfhout, S. S., Whittle, C. P., and Rouault, M., 2003. Observations of a young Agulhas ring, Astrid, during MARE in March 2000. Deep Sea Research Part II, 50: 167–195.CrossRefGoogle Scholar
  28. Weller, R. A., and Plueddemann, A. J., 1996. Observations of the vertical structure of the oceanic boundary layer. Journal Geophysical Research, 101(C4): 8789–8806.CrossRefGoogle Scholar
  29. Wong, A. P. S., Johnson, G. C., and Owens, W. B., 2003. Delayed-mode calibration of autonomous CTD profiling float salinity data by climatology. Journal of Atmospheric & Oceanic Technology, 20: 308–318.CrossRefGoogle Scholar
  30. Xie, S. P., Xu, L. X., Liu, Q., and Kobashi, F., 2011. Dynamical role of modewater ventilation in decadal variability in the central subtropical gyre of the North Pacific. Journal of Climate, 24: 1212–1225.CrossRefGoogle Scholar

Copyright information

© Science Press, Ocean University of China and Springer-Verlag Berlin Heidelberg 2013

Authors and Affiliations

  1. 1.Physical Oceanography LaboratoryOcean University of ChinaQingdaoP. R. China

Personalised recommendations