• Barnes, S. L., 1964: A technique for maximizing details in numerical weather map analysis. J. Appl. Meteor., 3, 396409, https://doi.org/10.1175/1520-0450(1964)003<0396:ATFMDI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Breitburg, D., and et al. , 2018: Declining oxygen in the global ocean and coastal waters. Science, 359, eaam7240, https://doi.org/10.1126/science.aam7240.

    • Crossref
    • Export Citation
  • Cai, W., and et al. , 2019: Pantropical climate interactions. Science, 363, eaav4236, https://doi.org/10.1126/science.aav4236.

    • Crossref
    • Export Citation
  • Capotondi, A., and M. A. Alexander, 2001: Rossby waves in the tropical North Pacific and their role in decadal thermocline variability. J. Phys. Oceanogr., 31, 34963515, https://doi.org/10.1175/1520-0485(2002)031<3496:RWITTN>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Capotondi, A., M. A. Alexander, and C. Deser, 2003: Why are there Rossby wave maxima in the Pacific at 10°S and 13°N? J. Phys. Oceanogr., 33, 15491563, https://doi.org/10.1175/2407.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Chelton, D. B., R. A. Deszoeke, M. G. Schlax, K. El Naggar, and N. Siwertz, 1998: Geographical variability of the first baroclinic Rossby radius of deformation. J. Phys. Oceanogr., 28, 433460, https://doi.org/10.1175/1520-0485(1998)028<0433:GVOTFB>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Cheng, L., and et al. , 2020: Improved estimates of changes in upper ocean salinity and the hydrological cycle. J. Climate, 33, 10 35710 381, https://doi.org/10.1175/JCLI-D-20-0366.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Dai, A., 2013: The influence of the inter-decadal Pacific oscillation on US precipitation during 1923–2010. Climate Dyn., 41, 633646, https://doi.org/10.1007/s00382-012-1446-5.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • de Boyer Montégut, C., J. Mignot, A. Lazar, and S. Cravatte, 2007: Control of salinity on the mixed layer depth in the world ocean: 1. General description. J. Geophys. Res., 112, C06011, https://doi.org/10.1029/2006JC003953.

    • Search Google Scholar
    • Export Citation
  • Dee, D. P., and et al. , 2011: The ERA-Interim reanalysis: Configuration and performance of the data assimilation system. Quart. J. Roy. Meteor. Soc., 137, 553597, https://doi.org/10.1002/qj.828.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • DeVries, T., M. Holzer, and F. Primeau, 2017: Recent increase in oceanic carbon uptake driven by weaker upper-ocean overturning. Nature, 542, 215218, https://doi.org/10.1038/nature21068.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Du, Y., Y. Zhang, M. Feng, T. Wang, N. Zhang, and S. Wijffels, 2015: Decadal trends of the upper ocean salinity in the tropical Indo-Pacific since mid-1990s. Sci. Rep., 5, 16050, https://doi.org/10.1038/srep16050.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Durack, P. J., and S. E. Wijffels, 2010: Fifty-year trends in global ocean salinities and their relationship to broad-scale warming. J. Climate, 23, 43424362, https://doi.org/10.1175/2010JCLI3377.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fedorov, A. V., R. C. Pacanowski, S. G. Philander, and G. Boccaletti, 2004: The effect of salinity on the wind-driven circulation and the thermal structure of the upper ocean. J. Phys. Oceanogr., 34, 19491966, https://doi.org/10.1175/1520-0485(2004)034<1949:TEOSOT>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feng, M., Y. Li, and G. Meyers, 2004: Multidecadal variations of Fremantle sea level: Footprint of climate variability in the tropical Pacific. Geophys. Res. Lett., 31, L16302, https://doi.org/10.1029/2004GL019947.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feng, M., M. J. McPhaden, and T. Lee, 2010: Decadal variability of the Pacific subtropical cells and their influence on the southeast Indian Ocean. Geophys. Res. Lett., 37, L09606, https://doi.org/10.1029/2010GL042796.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Feng, M., C. Böning, A. Biastoch, E. Behrens, E. Weller, and Y. Masumoto, 2011: The reversal of the multi-decadal trends of the equatorial Pacific easterly winds, and the Indonesian Throughflow and Leeuwin Current transports. Geophys. Res. Lett., 38, L11604, https://doi.org/10.1029/2011GL047291.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Folland, C. K., J. A. Renwick, M. J. Salinger, and A. B. Mullan, 2002: Relative influences of the Interdecadal Pacific Oscillation and ENSO on the South Pacific Convergence Zone. Geophys. Res. Lett., 29, 1643, https://doi.org/10.1029/2001GL014201.

    • Crossref
    • Export Citation
  • Forget, G., J. M. Campin, P. Heimbach, C. N. Hill, R. M. Ponte, and C. Wunsch, 2015: ECCO version 4: An integrated framework for non-linear inverse modeling and global ocean state estimation. Geosci. Model Dev., 8, 30713104, https://doi.org/10.5194/gmd-8-3071-2015.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Fu, W., J. T. Randerson, and J. Keith Moore, 2016: Climate change impacts on net primary production (NPP) and export production (EP) regulated by increasing stratification and phytoplankton community structure in the CMIP5 models. Biogeosciences, 13, 51515170, https://doi.org/10.5194/bg-13-5151-2016.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Gao, S., T. Qu, and X. Nie, 2014: Mixed layer salinity budget in the tropical Pacific Ocean estimated by a global GCM. J. Geophys. Res. Oceans, 119, 8410–8421, https://doi.org/10.1002/2014JC010336.

    • Crossref
    • Export Citation
  • Gordon, L. A., 1986: Interocean exchange of thermocline water. J. Geophys. Res., 91, 50375046, https://doi.org/10.1029/JC091iC04p05037.

  • Helm, K. P., N. L. Bindoff, and J. A. Church, 2010: Changes in the global hydrological-cycle inferred from ocean salinity. Geophys. Res. Lett., 37, L18701, https://doi.org/10.1029/2010GL044222.

    • Crossref
    • Export Citation
  • Hosoda, S., T. Ohira, and T. Nakamura, 2008: A monthly mean dataset of global oceanic temperature and salinity derived from Argo float observations. JAMSTEC Rep. Res. Dev., 8, 4759, https://doi.org/10.5918/jamstecr.8.47.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hu, S., and J. Sprintall, 2017: Observed strengthening of interbasin exchange via the Indonesian seas due to rainfall intensification. Geophys. Res. Lett., 44, 14481456, https://doi.org/10.1002/2016GL072494.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Hu, S., and et al. , 2019: Interannual to decadal variability of upper-ocean salinity in the southern Indian Ocean and the role of the Indonesian throughflow. J. Climate, 32, 64036421, https://doi.org/10.1175/JCLI-D-19-0056.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Kessler, S., 1990: Observations of long Rossby waves in the northern tropical Pacific. J. Geophys. Res., 95, 51835217, https://doi.org/10.1029/JC095iC04p05183.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lagerloef, G., 2012: Satellite mission monitors ocean surface salinity. Eos Trans. Amer. Geophys. Union, 93, 233234, https://doi.org/10.1029/2012EO250001.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lee, T., 2004: Decadal weakening of the shallow overturning circulation in the south Indian Ocean. Geophys. Res. Lett., 31, L18305, https://doi.org/10.1029/2004GL021774.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Lee, T., and M. J. McPhaden, 2008: Decadal phase change in large-scale sea level and winds in the Indo-Pacific region at the end of the 20th century. Geophys. Res. Lett., 35, L01605, https://doi.org/10.1029/2007GL032419.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, G., Y. Zhang, J. Xiao, X. Song, J. Abraham, L. Cheng, and J. Zhu, 2019: Examining the salinity change in the upper Pacific Ocean during the Argo period. Climate Dyn., 53, 60556074, https://doi.org/10.1007/s00382-019-04912-z.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, G., L. Cheng, J. Zhu, K. E. Trenberth, M. E. Mann, and J. P. Abraham, 2020: Increasing ocean stratification over the past half-century. Nat. Climate Change, 10, 11161123, https://doi.org/10.1038/s41558-020-00918-2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, H., F. Xu, W. Zhou, D. Wang, J. S. Wright, Z. Liu, and Y. Lin, 2017: Development of a global gridded Argo data set with Barnes successive corrections. J. Geophys. Res. Oceans, 122, 866889, https://doi.org/10.1002/2016JC012285.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Li, Y., and W. Han, 2015: Decadal sea level variations in the Indian Ocean investigated with HYCOM: Roles of climate modes, ocean internal variability, and stochastic wind forcing. J. Climate, 28, 91439165, https://doi.org/10.1175/JCLI-D-15-0252.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Liu, C., X. Liang, R. M. Ponte, N. Vinogradova, and O. Wang, 2019: Vertical redistribution of salt and layered changes in global ocean salinity. Nat. Commun., 10, 3445, https://doi.org/10.1038/s41467-019-11436-x.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Marshall, J., A. Adcroft, C. Hill, L. Perelman, and C. Heisey, 1997a: A finite-volume, incompressible Navier Stokes model for studies of the ocean on parallel computers. J. Geophys. Res. Oceans, 102, 57535766, https://doi.org/10.1029/96JC02775.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Marshall, J., C. Hill, L. Perelman, and A. Adcroft, 1997b: Hydrostatic, quasi-hydrostatic, and nonhydrostatic ocean modeling. J. Geophys. Res. Oceans, 102, 5733–5752, https://doi.org/10.1029/96JC02776.

    • Search Google Scholar
    • Export Citation
  • Masumoto, Y., and G. Meyers, 1998: Forced Rossby waves in the southern tropical Indian Ocean. J. Geophys. Res. Oceans, 103, 27 58927 602, https://doi.org/10.1029/98JC02546.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Menezes, V. V., H. E. Phillips, A. Schiller, N. L. Bindoff, C. M. Domingues, and M. L. Vianna, 2014: South Indian Countercurrent and associated fronts. J. Geophys. Res. Oceans, 119, 6763–6791, https://doi.org/10.1002/2014JC010076.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meng, L., W. Zhuang, W. Zhang, C. Yan, and X. H. Yan, 2020: Variability of the shallow overturning circulation in the Indian Ocean. J. Geophys. Res. Oceans, 125, e2019JC015651, https://doi.org/10.1029/2019JC015651.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Meyers, G., 1979: On the annual Rossby wave in the tropical North Pacific Ocean. J. Phys. Oceanogr., 9, 663–674, https://doi.org/10.1175/1520-0485(1979)009<0663:OTARWI>2.0.CO;2.

    • Crossref
    • Export Citation
  • Nagura, M., 2020: Variability in meridional transport of the subtropical circulation in the south Indian Ocean for the period from 2006 to 2017. J. Geophys. Res. Oceans, 125, e2019JC015874, https://doi.org/10.1029/2019JC015874.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nagura, M., and S. Kouketsu, 2018: Spiciness anomalies in the upper south Indian Ocean. J. Phys. Oceanogr., 48, 20812101, https://doi.org/10.1175/JPO-D-18-0050.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nagura, M., and M. J. McPhaden, 2021: Interannual variability in sea surface height at southern midlatitudes of the Indian Ocean. J. Phys. Oceanogr., 51, 1595–1609, https://doi.org/10.1175/JPO-D-20-0279.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Nie, X., Z. Wei, and Y. Li, 2020: Decadal variability in salinity of the Indian Ocean subtropical underwater during the Argo period. Geophys. Res. Lett., 47, e2020GL089104, https://doi.org/10.1029/2020GL089104.

    • Crossref
    • Export Citation
  • Pokhrel, S., H. Rahaman, A. Parekh, S. K. Saha, A. Dhakate, H. S. Chaudhari, and R. M. Gairola, 2012: Evaporation-precipitation variability over Indian Ocean and its assessment in NCEP Climate Forecast System (CFSv2). Climate Dyn., 39, 25852608, https://doi.org/10.1007/s00382-012-1542-6.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Ponte, R. M., and N. T. Vinogradova, 2016: An assessment of basic processes controlling mean surface salinity over the global ocean. Geophys. Res. Lett., 43, 7052–7058, https://doi.org/10.1002/2016GL069857.

    • Crossref
    • Export Citation
  • Power, S., T. Casey, C. Folland, A. Colman, and V. Mehta, 1999: Inter-decadal modulation of the impact of ENSO on Australia. Climate Dyn., 15, 319324, https://doi.org/10.1007/s003820050284.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qiu, B., and S. Chen, 2010: Interannual-to-decadal variability in the bifurcation of the north equatorial current off the Philippines. J. Phys. Oceanogr., 40, 25252538, https://doi.org/10.1175/2010JPO4462.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qu, T., and G. Meyers, 2005: Seasonal characteristics of circulation in the southeastern tropical Indian Ocean. J. Phys. Oceanogr., 35, 255267, https://doi.org/10.1175/JPO-2682.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qu, T., S. Gao, and I. Fukumori, 2013: Formation of salinity maximum water and its contribution to the overturning circulation in the North Atlantic as revealed by a global general circulation model. J. Geophys. Res. Oceans, 118, 19821994, https://doi.org/10.1002/jgrc.20152.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Qu, T., Z. Lian, X. Nie, and Z. Wei, 2019: Eddy-induced meridional salt flux and its impacts on the sea surface salinity maxima in the southern subtropical oceans. Geophys. Res. Lett., 46, 11 29211 300, https://doi.org/10.1029/2019GL084807.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Reul, N., and et al. , 2014: Sea surface salinity observations from space with the SMOS satellite: A new means to monitor the marine branch of the water cycle. Surv. Geophys., 35, 681722, https://doi.org/10.1007/s10712-013-9244-0.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Roemmich, D., and J. Gilson, 2009: The 2004–2008 mean and annual cycle of temperature, salinity, and steric height in the global ocean from the Argo Program. Prog. Oceanogr., 82, 81100, https://doi.org/10.1016/j.pocean.2009.03.004.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Roemmich, D., M. Morris, W. R. Young, and J. R. Donguy, 1994: Fresh equatorial jets. J. Phys. Oceanogr., 24, 540558, https://doi.org/10.1175/1520-0485(1994)024<0540:FEJ>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Schmitt, R. W., 2008: Salinity and the global water cycle. Oceanography, 21, 1219, https://doi.org/10.5670/oceanog.2008.63.

  • Sprintall, J., and M. Tomczak, 1992: Evidence of the barrier layer in the surface layer of the tropics. J. Geophys. Res., 97, 7305, https://doi.org/10.1029/92JC00407.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Stuecker, M. F., 2018: Revisiting the Pacific meridional mode. Sci. Rep., 8 3216, https://doi.org/10.1038/s41598-018-21537-0.

  • Sun, Q., Y. Du, S.-P. Xie, Y. Zhang, M. Wang, and Y. Kosaka, 2021: Sea surface salinity change since 1950: Internal variability versus anthropogenic forcing. J. Climate, 34, 13051319, https://doi.org/10.1175/JCLI-D-20-0331.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Toole, J. M., and B. A. Warren, 1993: A hydrographic section across the subtropical south Indian Ocean. Deep-Sea Res. I, 40, 19732019, https://doi.org/10.1016/0967-0637(93)90042-2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Trenary, L. L., and W. Han, 2013: Local and remote forcing of decadal sea level and thermocline depth variability in the south Indian Ocean. J. Geophys. Res. Oceans, 118, 381398, https://doi.org/10.1029/2012JC008317.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Vinogradova, N. T., and R. M. Ponte, 2017: In search of fingerprints of the recent intensification of the ocean water cycle. J. Climate, 30, 55135528, https://doi.org/10.1175/JCLI-D-16-0626.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Volkov, D. L., S.-K. Lee, A. L. Gordon, and M. Rudko, 2020: Unprecedented reduction and quick recovery of the south Indian Ocean heat content and sea level in 2014–2018. Sci. Adv., 6, eabc1151, https://doi.org/10.1126/sciadv.abc1151.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, C., 2019: Three-ocean interactions and climate variability: A review and perspective. Climate Dyn., 53, 51195136, https://doi.org/10.1007/s00382-019-04930-x.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wang, T. Y., Y. Du, W. Zhuang, and J. B. Wang, 2015: Connection of sea level variability between the tropical western Pacific and the southern Indian Ocean during recent two decades. Sci. China Earth Sci., 58, 13871396, https://doi.org/10.1007/s11430-014-5048-4.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wijffels, S., and G. Meyers, 2004: An intersection of oceanic waveguides: Variability in the Indonesian Throughflow region. J. Phys. Oceanogr., 34, 12321253, https://doi.org/10.1175/1520-0485(2004)034<1232:AIOOWV>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Wunsch, C., P. Heimbach, R. Ponte, and I. Fukumori, 2009: The global general circulation of the ocean estimated by the ECCO-Consortium. Oceanography, 22, 88103, https://doi.org/10.5670/oceanog.2009.41.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xie, S.-P., H. Annamalai, F. A. Schott, and J. P. McCreary, 2002: Structure and mechanisms of south Indian Ocean climate variability. J. Climate, 15, 864878, https://doi.org/10.1175/1520-0442(2002)015<0864:SAMOSI>2.0.CO;2.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Xie, S.-P., Y. Du, G. Huang, X.-T. Zheng, H. Tokinaga, K. Hu, and Q. Liu, 2010: Decadal shift in El Niño influences on Indo–western Pacific and East Asian climate in the 1970s. J. Climate, 23, 33523368, https://doi.org/10.1175/2010JCLI3429.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yu, L., 2011: A global relationship between the ocean water cycle and near-surface salinity. J. Geophys. Res. Oceans, 116, C10025, https://doi.org/10.1029/2010JC006937.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Yu, W., B. Xiang, L. Liu, and N. Liu, 2005: Understanding the origins of interannual thermocline variations in the tropical Indian Ocean. Geophys. Res. Lett., 32, L24706, https://doi.org/10.1029/2005GL024327.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhang, L. Y., Y. Du, W. Cai, Z. Chen, T. Tozuka, and J. Y. Yu, 2020: Triggering the Indian Ocean dipole from the Southern Hemisphere. Geophys. Res. Lett., 47, e2020GL088648, https://doi.org/10.1029/2020GL088648.

    • Search Google Scholar
    • Export Citation
  • Zhang, N., M. Feng, Y. Du, J. Lan, and S. E. Wijffels, 2016: Seasonal and interannual variations of mixed layer salinity in the southeast tropical Indian Ocean. J. Geophys. Res. Oceans, 121, 47164731, https://doi.org/10.1002/2016JC011854.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhang, Y., M. Feng, Y. Du, H. E. Phillips, N. L. Bindoff, and M. J. McPhaden, 2018b: Strengthened Indonesian throughflow drives decadal warming in the southern Indian Ocean. Geophys. Res. Lett., 45, 61676175, https://doi.org/10.1029/2018GL078265.

    • Search Google Scholar
    • Export Citation
  • Zhang, Y.-H., Y. Du, S. Zheng, Y. Yang, Y., and X. Cheng, 2013: Impact of Indian Ocean dipole on the salinity budget in the equatorial Indian Ocean. J. Geophys. Res. Oceans, 118, 49114923, https://doi.org/10.1002/jgrc.20392.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhang, Y., Y. Du, and M. Feng, 2018a: Multiple time scale variability of the sea surface salinity dipole mode in the tropical Indian Ocean. J. Climate, 31, 283296, https://doi.org/10.1175/JCLI-D-17-0271.1.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zheng, X. T., 2019: Indo-Pacific climate modes in warming climate: Consensus and uncertainty across model projections. Curr. Climate Change Rep., 5, 308321, https://doi.org/10.1007/s40641-019-00152-9.

    • Crossref
    • Search Google Scholar
    • Export Citation
  • Zhuang, W., M. Feng, Y. Du, A. Schiller, and D. Wang, 2013: Low-frequency sea level variability in the southern Indian Ocean and its impacts on the oceanic meridional transports. J. Geophys. Res. Oceans, 118, 13021315, https://doi.org/10.1002/jgrc.20129.

    • Crossref
    • Search Google Scholar
    • Export Citation
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Decadal Variability of the Upper-Ocean Salinity in the Southeast Indian Ocean: Role of Local Ocean–Atmosphere Dynamics

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  • 1 a Key Laboratory of Physical Oceanography, Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, China
  • | 2 b Laboratory for Ocean Dynamics and Climate, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
  • | 3 c State Key Laboratory of Tropical Oceanography, South China Sea Institute of Oceanology and Innovation Academy of South China Sea Ecology and Environmental Engineering, Chinese Academy of Sciences, Guangzhou, China
  • | 4 d College of Marine Science, University of Chinese Academy of Sciences, Beijing, China
  • | 5 e Southern Marine Science and Engineering Guangdong Laboratory, Guangzhou, China
  • | 6 f Southern Marine Science and Engineering Guangdong Laboratory (Zhuhai), Zhuhai, China
  • | 7 g First Institute of Oceanography, and Key Laboratory of Marine Science and Numerical Modeling, Ministry of Natural Resources, Qingdao, China
  • | 8 h Shandong Key Laboratory of Marine Science and Numerical Modeling, Qingdao, China
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Abstract

Ocean salinity plays a crucial role in the upper-ocean stratification and local marine ecosystem. This study reveals that ocean salinity presents notable decadal variability in upper 200 m over the southeast Indian Ocean (SEIO). Previous studies linked this salinity variability with precipitation anomalies over the Indo-Pacific region modulated by the tropical Pacific decadal variability. Here we conduct a quantitative salinity budget analysis and show that, in contrast, oceanic advection, especially the anomalous meridional advection, plays a dominant role in modulating the SEIO salinity on the decadal time scale. The anomalous meridional advection is mainly associated with a zonal dipole pattern of sea level anomaly (SLA) in the south Indian Ocean (SIO). Specifically, positive and negative SLAs in the east and west of the SIO correspond to anomalous southward oceanic current, which transports much fresher seawater from the warm pool into the SEIO and thereby decreases the local upper-ocean salinity, and vice versa. Further investigation reveals that the local anomalous wind stress curl associated with tropical Pacific forcing is responsible for generating the sea level dipole pattern via oceanic Rossby wave adjustment on decadal time scale. This study highlights that the local ocean–atmosphere dynamical adjustment is critical for the decadal salinity variability in the SEIO.

© 2021 American Meteorological Society. For information regarding reuse of this content and general copyright information, consult the AMS Copyright Policy (www.ametsoc.org/PUBSReuseLicenses).

Corresponding author: Xiao-Tong Zheng, zhengxt@ouc.edu.cn

Abstract

Ocean salinity plays a crucial role in the upper-ocean stratification and local marine ecosystem. This study reveals that ocean salinity presents notable decadal variability in upper 200 m over the southeast Indian Ocean (SEIO). Previous studies linked this salinity variability with precipitation anomalies over the Indo-Pacific region modulated by the tropical Pacific decadal variability. Here we conduct a quantitative salinity budget analysis and show that, in contrast, oceanic advection, especially the anomalous meridional advection, plays a dominant role in modulating the SEIO salinity on the decadal time scale. The anomalous meridional advection is mainly associated with a zonal dipole pattern of sea level anomaly (SLA) in the south Indian Ocean (SIO). Specifically, positive and negative SLAs in the east and west of the SIO correspond to anomalous southward oceanic current, which transports much fresher seawater from the warm pool into the SEIO and thereby decreases the local upper-ocean salinity, and vice versa. Further investigation reveals that the local anomalous wind stress curl associated with tropical Pacific forcing is responsible for generating the sea level dipole pattern via oceanic Rossby wave adjustment on decadal time scale. This study highlights that the local ocean–atmosphere dynamical adjustment is critical for the decadal salinity variability in the SEIO.

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Corresponding author: Xiao-Tong Zheng, zhengxt@ouc.edu.cn
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