Advances in Atmospheric Sciences

, Volume 36, Issue 4, pp 397–416 | Cite as

Errors in Current Velocity in the Low-latitude North Pacific: Results from the Regional Ocean Modeling System

  • Xixi Wen
  • Wansuo DuanEmail author
Original Paper


Using the Regional Ocean Modeling System, this study investigates the simulation uncertainties in the current velocity in the low-latitude North Pacific where the Kuroshio originates [i.e., the beginning of the Kuroshio (BK)]. The results show that the simulation uncertainties largely reflect the contributions of wind stress forcing errors, especially zonal wind stress errors, rather than initial or boundary errors. Using the idea of a nonlinear forcing singular vector, two types of zonal wind stress errors (but sharing one EOF mode) are identified from error samples derived from reanalysis data as having the potential to yield large simulation uncertainties. The type-1 error possesses a pattern with positive anomalies covering the two zonal bands of 0°–15°N and 25°–40°N in the Pacific Ocean, with negative anomalies appearing between these two bands; while the type-2 error is almost opposite to the type-1 error. The simulation uncertainties induced by the type-1 and −2 errors consist of both large-scale circulation errors controlled by a mechanism similar to the Sverdrup relation and mesoscale eddy-like errors generated by baroclinic instability. The type-1 and −2 errors suggest two areas: one is located between the western boundary and the meridional 130°E along 15°–20°N, and the other is located between 140°–150°E and along 15°–20°N. The reduction of errors over these two areas can greatly improve the simulation accuracy of the current velocity at BK. These two areas represent sensitive areas for targeted observations associated with the simulation of the current velocity at BK.

Key words

Kuroshio nonlinear forcing singular vector targeted observation 

摘 要

该研究使用著名的区域海洋模式ROMS(Regional Ocean Modeling System), 对源区黑潮流速的模拟不确定性进行了解剖式研究. 结果表明, 在驱动模式运行的初始条件, 边界条件, 以及风应力外强迫中, 风应力强迫误差, 特别是纬向风应力误差常常导致源区黑潮流速具有更大的模拟误差. 为了揭示对源区黑潮模拟不确定性具有最大影响的纬向风应力误差, 本研究基于历史分析资料, 利用集合的办法, 识别了对源区黑潮具有最大影响的非线性强迫奇异向量(nonlinear forcing singular vector; NFSV)型-纬向风应力误差. 该误差可分为两种类型, 即type-1和type-2误差. type-1误差位于0º–15ºN, 25º–40ºN两个纬度带内, 且表现为横跨太平洋海盆的正风应力误差, 而在这两个纬度带之间的区域, type-1误差则表现为横跨太平洋海盆的负风应力误差; type-2误差与type-1型结构相同, 但符号几乎相反. type-1和type-2误差对源区黑潮流速模拟的影响, 一方面通过改变大尺度海洋环流影响源区黑潮的模拟; 另一方面则诱发海洋中尺度涡, 并促使其西移而影响源区黑潮. 根据type-1和type-2误差, 并通过敏感性实验, 确定了能够有效改善源区黑潮模拟效果的目标观测敏感区, 即位于15º–20ºN之间, 呈东西分布, 且包含两个区域: 一个区域位于西边界与130ºE之间; 另一个则位于135º–150ºE之间.


源区黑潮 模拟不确定性 非线性强迫奇异向量 目标观测 


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.



This work was jointly sponsored by the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDA11010303) and the National Natural Science Foundation of China (Grant No. 41525017). ROMS is open source and can be downloaded from The present study adopted data from GODAS, CORE.v2, SODA 2.1.6, and ERA-Interim. They can be obtained from,,, and, respectively.


  1. Balmaseda, M. A., A. Vidard, and D. L. T. Anderson, 2008: The ECMWF ocean analysis system: ORA-S3. Mon. Wea. Rev., 136, 3018–3034, Scholar
  2. Behringer, D. W., Y. Xue, 2004: Evaluation of the global ocean data assimilation system at NCEP: The Pacific Ocean. Eighth Symposium on Integrated Observing and Assimilation Systems for Atmosphere, Oceans, and Land Surface, AMS 84th Annual Meeting, Washington State Convention and Trade Center, Seattle, Washington, 11–15.Google Scholar
  3. Carton, J. A., and B. S. Giese, 2008: A reanalysis of ocean climate using simple ocean data assimilation (SODA). Mon. Wea. Rev., 136, 2999–3017, Scholar
  4. Centurioni, L. R., P. P. Niiler, and D.-K. Lee, 2004: Observations of inflow of philippine sea surface water into the South China Sea through the Luzon Strait. J. Phys. Oceanogr., 34, 113–121,<0113:OOIOPS>2.0.CO;2.CrossRefGoogle Scholar
  5. Chelton, D. B., and M. G. Schlax, 1996: Global observations of oceanic rossby waves. Science, 272, 234–238, Scholar
  6. Dee, D. P., and Coauthors, 2011: The ERA-Interim reanalysis: Configuration and performance of the data assimilation system. Quart. J. Roy. Meteor. Soc., 137, 553–597, Scholar
  7. Du, C., and Coauthors, 2013: Impact of the Kuroshio intrusion on the nutrient inventory in the upper northern South China Sea: Insights from an isopycnal mixing model. Biogeosciences, 10, 6419–6432, Scholar
  8. Duan, W. S., and C. Wei, 2013: The ‘spring predictability barrier’ for ENSO predictions and its possible mechanism: Results from a fully coupled model. International Journal of Climatology, 33, 1280–1292, Scholar
  9. Duan, W. S., and P. Zhao, 2015: Revealing the most disturbing tendency error of Zebiak–Cane model associated with El Niño predictions by nonlinear forcing singular vector approach. Climate Dyn., 44, 2351–2367, Scholar
  10. Duan, W. S., and F. F. Zhou, 2013: Non-linear forcing singular vector of a two-dimensional quasi-geostrophic model. Tellus A, 65, 18452, Scholar
  11. Duan, W. S., and J. Y. Hu, 2016: The initial errors that induce a significant “spring predictability barrier” for El Niño events and their implications for target observation: Results from an earth system model. Climate Dyn., 46, 3599–3615, Scholar
  12. Duan, W. S., X. C. Liu, K. Y. Zhu, and M. Mu, 2009: Exploring the initial errors that cause a significant “spring predictability barrier” for El Niño events. J. Geophys. Res., 114, C04022, Scholar
  13. Fang, G. H., W. Fang, Y. Fang, and K. Wang, 1998: A survey of studies on the South China Sea upper ocean circulation. Acta Oceanogr. Taiwanica, 37, 1–16.Google Scholar
  14. Fujii, Y., H. Tsujino, N. Usui, H. Nakano, and M. Kamachi, 2008: Application of singular vector analysis to the Kuroshio large meander. J. Geophys. Res., 113, C07026, Scholar
  15. Gordon, A. L., P. Flament, C. Villanoy, and L. Centurioni, 2014: The nascent Kuroshio of Lamon Bay. J. Geophys. Res., 119, 4251–4263, Scholar
  16. Gu, D.-F., and S. G. H. Philander, 1997: Interdecadal climate fluctuations that depend on exchanges between the tropics and extratropics. Science, 275, 805–807, Scholar
  17. Haidvogel, D. B., H. G. Arango, K. Hedstrom, A. Beckmann, P. Malanotte-Rizzoli, and A. F. Shchepetkin, 2000: Model evaluation experiments in the North Atlantic Basin: Simulations in nonlinear terrain-following coordinates. Dyn. Atmos. Oceans, 32, 239–281, Scholar
  18. Haidvogel, D. B., and Coauthors, 2008: Ocean forecasting in terrain-following coordinates: Formulation and skill assessment of the Regional Ocean Modeling System. J. Comput. Phys., 227, 3595–3624, Scholar
  19. Hautala, S. L., D. H. Roemmich, and W. J. Schmilz, Jr., 1994: Is the North Pacific in Sverdrup balance along 24°N? J. Geophys. Res., 99, 16 041–16 052, Scholar
  20. Hu, D. X., and M. C. Cui, 1991: The Western Boundary Current of the pacific and its role in the climate. Chinese Journal of Oceanology and Limnology, 9, 1–14, Scholar
  21. Hu, D. X., and Coauthors, 2013: Direct measurements of the luzon undercurrent. J. Phys. Oceanogr., 43, 1417–1425, Scholar
  22. Hu, D. X., and Coauthors, 2015: Pacific western boundary currents and their roles in climate. Nature, 522, 299–308, Scholar
  23. Jan, S., and Coauthors, 2015: Large variability of the Kuroshio at 23.75°N east of Taiwan. J. Geophys. Res., 120, 1825–1840, Scholar
  24. Jiang, H., H. Wang, J. Zhu, and B. K. Tan, 2006: Relationship between real meridional volume transport and Sverdrup transport in the North Subtropical Pacific. Chinese Science Bulletin, 51, 1757–1760, Scholar
  25. Kanamitsu, M., W. Ebisuzaki, J. Woollen, S. K. Yang, J. J. Hnilo, M. Fiorino, and G. L. Potter, 2002: NCEP-DOE AMIP-II reanalysis (R-2). Bull. Amer. Meteor. Soc., 83, 1631–1644, Scholar
  26. Kaneko, A. M., and Coauthors, 1998: ADCP observation of the western equatorial pacific by a commercial ship. Umi, 7(6), 357–368, Scholar
  27. Kashino, Y., N. España, F. Syamsudin, K. J. Richards, T. Jensen, P. Dutrieux, and A. Ishida, 2009: Observations of the north equatorial current, mindanao current, and kuroshio current system during the 2006/07 El Niño and 2007/08 La Niña. Journal of Oceanography, 65, 325–333, Scholar
  28. Kim, Y. Y., T. D. Qu, T. Jensen, T. Miyama, H. Mitsudera, H. W. Kang, and A. Ishida, 2004: Seasonal and interannual variations of the north equatorial current bifurcation in a highresolution OGCM. J. Geophys. Res., 109, C03040, Scholar
  29. Large, W. G., and S. G. Yeager, 2009: The global climatology of an interannually varying air - sea flux data set. Climate Dyn., 33, 341–364, Scholar
  30. Latif, M., and T. P. Barnett, 1994: Causes of decadal climate variability over the North Pacific and North America. Science, 266, 634–637, Scholar
  31. Li, J. J., X. Jiang, G. Li, Z. Y. Jing, L. B. Zhou, Z. X. Ke, and Y. H. Tan, 2017: Distribution of picoplankton in the northeastern South China Sea with special reference to the effects of the Kuroshio intrusion and the associated mesoscale eddies. Science of the Total Environment, 589, 1–10, Scholar
  32. Lien, R.-C., B. Ma, Y. H. Cheng, C. R. Ho, B. Qiu, C. M. Lee, and M. H. Chang, 2014: Modulation of Kuroshio transport by mesoscale eddies at the Luzon Strait entrance. J. Geophys. Res., 119, 2129–2142, Scholar
  33. Lien, R.-C., and Coauthors, 2015: The Kuroshio and Luzon undercurrent east of Luzon Island. Oceanography, 28, 54–63, Scholar
  34. Lu, J., and Q. Liu, 2013: Gap-leaping kuroshio and blocking westward-propagating rossby wave and eddy in the luzon strait. J. Geophys. Res., 118(3), 1170–1181, Scholar
  35. Macdonald, A. M., and C. Wunsch, 1996: An estimate of global ocean circulation and heat fluxes. Nature, 382, 436–439, Scholar
  36. Majumdar, S. J., 2016: A review of targeted observations. Bull. Amer. Meteor. Soc., 97, 2287–2303, Scholar
  37. McCreary, J. P. Jr., and P. Lu, 1994: Interaction between the subtropical and equatorial ocean circulations: The subtropical cell. J. Phys. Oceanogr., 24, 466–497,<0466:IBTSAE>2.0.CO;2.CrossRefGoogle Scholar
  38. Mu, M., 2013: Methods, current status, and prospect of targeted observation. Science China Earth Sciences, 56, 1997–2005, Scholar
  39. Nakano, T., I., Kaneko, M., Endoh, and M., Kamachi, 2005: Interannual and decadal variabilities of npiw salinity minimum core observed along jma’s hydrographic repeat sections. Journal of Oceanography, 61(4), 681–697, Scholar
  40. Nan, F., H. J. Xue, F. Chai, L. Shi, M. C. Shi, and P. F. Guo, 2011: Identification of different types of Kuroshio intrusion into the South China Sea. Ocean Dynamics, 61, 1291–1304, Scholar
  41. Nan, F., F. Yu, H. J. Xue, L. L. Zeng, D. X. Wang, S. L. Yang, and K. C. Nguyen, 2016: Freshening of the upper ocean in the South China Sea since the early 1990s. Deep Sea Research Part I: Oceanographic Research Papers, 118, 20–29, Scholar
  42. Nitani, H., 1972: Beginning of the Kuroshio. Kuroshio: Physical Aspects of the Japan Current, H. Stommel and K. Yashida., Eds., University of Washington Press, 129–163.Google Scholar
  43. Prakash, K. R., and V. Pant, 2017: Upper oceanic response to tropical cyclone Phailin in the Bay of Bengal using a coupled atmosphere-ocean model. Ocean Dynamics, 67, 51–64, Scholar
  44. Qiu, B., 1999: Seasonal eddy field modulation of the North Pacific subtropical countercurrent: TOPEX/Poseidon observations and theory. J. Phys. Oceanogr., 29, 2471–2486,<2471:SEFMOT>2.0.CO;2.CrossRefGoogle Scholar
  45. Qiu, B., and R. Lukas, 1996: Seasonal and interannual variability of the North Equatorial Current, the Mindanao Current, and the Kuroshio along the Pacific western boundary. J. Geophys. Res., 101, 12 315–12 330, Scholar
  46. Qiu, B., and S. M. Chen, 2010: Interannual variability of the North Pacific subtropical countercurrent and its associated mesoscale eddy field. J. Phys. Oceanogr., 40, 213–225, Scholar
  47. Qiu, B., T. Nakano, S. M. Chen, and P. Klein, 2017: Submesoscale transition from geostrophic flows to internal waves in the northwestern Pacific upper ocean. Nature Communications, 8, 14055, Scholar
  48. Qu, T. D., H. Mitsudera, and T. Yamagata, 1998: On the western boundary currents in the Philippine Sea. J. Geophys. Res., 103, 7537–7548, Scholar
  49. Qu, T. D., Y. Y. Kim, M. Yaremchuk, T. Tozuka, A. Ishida, and T. Yamagata, 2004: Can Luzon Strait transport play a role in conveying the impact of ENSO to the South China Sea?. J. Climate, 17, 3644–3657,<3644:CLSTPA>2.0.CO;2.CrossRefGoogle Scholar
  50. Rudnick, D. L., and Coauthors, 2011: Seasonal and mesoscale variability of the Kuroshio near its origin. Oceanography, 24, 52–63, Scholar
  51. Shchepetkin, A. F., and J. C. McWilliams, 2003: A method for computing horizontal pressure-gradient force in an oceanic model with a nonaligned vertical coordinate. J. Geophys. Res., 108, 3090, Scholar
  52. Shchepetkin, A. F., and J. C. McWilliams, 2005: The regional oceanic modeling system (ROMS): A split-explicit, freesurface, topography-following-coordinate oceanic model. Ocean Modelling, 9, 347–404, Scholar
  53. Sheremet, V. A., and J. Kuehl, 2007: Gap-leaping western boundary current in a circular tank model. J. Phys. Oceanogr., 37, 1488–1495, Scholar
  54. Song, Y. H., and D. Haidvogel, 1994: A semi-implicit ocean circulation model using a generalized topography-following coordinate system. J. Comput. Phys., 115, 228–244, Scholar
  55. Stommel, H., 1948: The westward intensification of wind-driven ocean currents. Eos, Trans. Amer. Geophys. Union, 29, 202–206, Scholar
  56. Tao, L. J., R.-H. Zhang, and C. Gao, 2017: Initial error-induced optimal perturbations in ENSO predictions, as derived from an intermediate coupled model. Adv. Atmos. Sci., 34(6), 791–803, Scholar
  57. Trenberth, K. E., and J. M. Caron, 2001: Estimates of meridional atmosphere and ocean heat transports. J. Climate, 14, 3433–3443,<3433:EOMAAO>2.0.CO;2.CrossRefGoogle Scholar
  58. Wang, F., N. Zang, Y. L. Li, and D. X. Hu, 2015: On the subsurface countercurrents in the Philippine Sea. J. Geophys. Res., 120, 131–144, Scholar
  59. Wang, Q., and M. Mu, 2015: A new application of conditional nonlinear optimal perturbation approach to boundary condition uncertainty. J. Geophys. Res., 120(12), 7979–7996, Scholar
  60. Wang, Q., M. Mu, and H. A. Dijkstra, 2013: The similarity between optimal precursor and optimally growing initial error in prediction of Kuroshio large meander and its application to targeted observation. J. Geophys. Res., 118, 869–884, Scholar
  61. Wang, Q. Y., and D. X. Hu, 2012: Origin of the Luzon undercurrent. Bulletin of Marine Science, 88, 51–60, Scholar
  62. Wunsch, C., 2005: The total meridional heat flux and its oceanic and atmospheric partition. J. Climate, 18, 4374–4380, Scholar
  63. Xiao, F., L. L. Zeng, Q. Y. Liu, W. Zhou, and D. X. Wang, 2018: Extreme subsurface warm events in the South China Sea during 1998/99 and 2006/07: Observations and mechanisms. Climate Dyn., 50, 115–128, Scholar
  64. Yu, Y., Mu, M., W. Duan, and T. Gong, 2012: Contribution of the location and spatial pattern of initial error to uncertainties in El Niño predictions. J. Geophys. Res., 117, Scholar
  65. Zhai, F. G., D. X. Hu, Q. Y. Wang, and F. J. Wang, 2014: Longterm trend of Pacific South Equatorial Current bifurcation over 1950–2010. Geophys. Res. Lett., 41, 3172–3180, Scholar
  66. Zhang, K., Q. Wang, M. Mu, and P. Liang, 2016: Effects of optimal initial errors on predicting the seasonal reduction of the upstream Kuroshio transport. Deep Sea Research Part I: Oceanographic Research Papers, 116, 220–235, Scholar
  67. Zhang, K., M. Mu, and Q. Wang, 2017: Identifying the sensitive area in adaptive observation for predicting the upstream Kuroshio transport variation in a 3-D ocean model. Science China Earth Sciences, 60, 866–875, Scholar
  68. Zhao, Y. P., and G. A. McBean, 1986: Annual and interannual variability of the North Pacific ocean-to-atmosphere total heat transfer. Atmos.-Ocean, 24, 265–282, Scholar
  69. Zou, G. A., Q. Wang, and M. Mu, 2016: Identifying sensitive areas of adaptive observations for prediction of the Kuroshio large meander using a shallow-water model. Chinese Journal of Oceanology and Limnology, 34, 1122–1133, Scholar

Copyright information

© Chinese National Committee for International Association of Meteorology and Atmospheric Sciences, Institute of Atmospheric Physics, Science Press and Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.The State Key Laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical Fluid Dynamics, Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina
  2. 2.University of Chinese Academy of SciencesBeijingChina

Personalised recommendations