Climate Dynamics

, Volume 49, Issue 11–12, pp 3887–3904 | Cite as

Causes for the reversal of North Indian Ocean decadal sea level trend in recent two decades

  • U. Srinivasu
  • M. Ravichandran
  • Weiqing Han
  • S. Sivareddy
  • H. Rahman
  • Yuanlong Li
  • Shailesh Nayak


Using satellite and in-situ observations, ocean reanalysis products and model simulations, we show a distinct reversal of the North Indian Ocean (NIO, north of 5°S) sea level decadal trend between 1993–2003 and 2004–3013, after the global mean sea level rise is removed. Sea level falls from 1993 to 2003 (Period I) but rises sharply from 2004 to 2013 (Period II). Steric height, which is dominated by thermosteric sea level of the upper 700 m, explains most of the observed reversal, including the spatial patterns of sea level change. The decadal change of surface turbulent heat flux acts in concert with the change of meridional heat transport at 5°S, with both being driven by decadal change of surface winds over the Indian Ocean, to cause sea level fall during Period I and rise during Period II. While the effect of surface net heat flux is consistent among various data sets, the uncertainty is larger for meridional heat transport, which shows both qualitative and quantitative differences amongst different reanalyses. The effect of the Indonesian Throughflow on heat content and thus thermosteric sea level is limited to the South Indian Ocean, and has little influence on the NIO. Our new results point to the importance of surface winds in causing decadal sea level change of the NIO.


North Indian Ocean Sea level Decadal change Surface winds 



The authors are grateful for all the organizations and persons who made the datasets used in this research freely available. We thank two anonymous reviewers to critically go through the manuscript and provide us valuable suggestions to improve the content of the manuscript. Special thanks to Drl Jerome Vialard for his valuable suggestions to improve the manuscript. AVISO monthly sea level anomaly maps are downloaded from NOCS v2.0 heat flux data, Ishii and Japan reanalysis data (JRA-55) are available at EN4_v2a objective analysis data, ORAS4 reanalysis, OAFlux flux data, wind data (ERA-Interim, NCEP and CCMP), monthly HadISST are downloaded from Tropflux data is available at ERA-Interim evaporation and precipitation data is found at The encouragement and facilities provided by the Director, ESSO-INCOIS are gratefully acknowledged. The authors wish to acknowledge the use of the Ferret program (NOAA) for analysis and graphics in this paper. The authors gratefully acknowledge the financial support provided by the Earth System Science Organization, Ministry of Earth Sciences, and the government of India, to conduct this research. The National Monsoon Mission Directorate award number SSC-03-002 was awarded to Weiqing Han at the University of Colorado, in collaboration with ESSO-INCOIS. Weiqing Han is also partly supported by NSF AGS 1446480 and NASA OVWST NNX14AM68G. This is ESSO-INCOIS contribution No. 0275.


  1. Atlas R, Hoffman RN, Ardizzone J, et al (2009) Development of a new cross-calibrated, multi-platform (CCMP) ocean surface wind product. In: AMS 13th Conference on Integrated Observing and Assimilation Systems for Atmosphere, Oceans, and Land Surface (IOAS-AOLS)Google Scholar
  2. Balmaseda MA, Mogensen K, Weaver AT (2013) Evaluation of the ECMWF ocean reanalysis system ORAS4. Q J R Meteorol Soc 139:1132–1161. doi: 10.1002/qj.2063 CrossRefGoogle Scholar
  3. Behringer DW, Xue Y (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, pp 11–15Google Scholar
  4. Berry DI, Kent EC (2011) Air-Sea fluxes from ICOADS: the construction of a new gridded dataset with uncertainty estimates. Int J Climatol 31:987–1001. doi: 10.1002/joc.2059 CrossRefGoogle Scholar
  5. Bobba AG (2002) Numerical modelling of salt-water intrusion due to human activities and sea-level change in the Godavari Delta, India. Hydrol Sci J 47:S67–S80. doi: 10.1080/02626660209493023 CrossRefGoogle Scholar
  6. Cazenave A, Cozannet GL (2014) Sea level rise and its coastal impacts: CAZENAVE AND LE COZANNET. Earths Future 2:15–34. doi: 10.1002/2013EF000188 CrossRefGoogle Scholar
  7. Chen G, Han W, Li Y, Wang D, McPhaden M (2015) Seasonal-to-interannual time scale dynamics of the equatorial undercurrent in the Indian Ocean. J Phys Oceanogr 45:1532–1553. doi: 10.1175/JPO-D-14-0225.1 CrossRefGoogle Scholar
  8. Cheng X, Qi Y, Zhou W (2008) Trends of sea level variations in the Indo-Pacific warm pool. Glob Planet Change 63:57–66. doi: 10.1016/j.gloplacha.2008.06.001 CrossRefGoogle Scholar
  9. Church JA, White NJ, Konikow LF, et al (2011) Revisiting the Earth’s sea-level and energy budgets from 1961 to 2008: sea-level and energy budgets. Geophys Res Lett doi: 10.1029/2011GL048794 Google Scholar
  10. Compo GP, Whitaker JS, Sardeshmukh PD, et al (2011) The Twentieth Century Reanalysis Project. Q J R Meteorol Soc 137:1–28. doi: 10.1002/qj.776 CrossRefGoogle Scholar
  11. Dee DP, Uppala SM, Simmons AJ, et al (2011) The ERA-Interim reanalysis: configuration and performance of the data assimilation system. Q J R Meteorol Soc 137:553–597. doi: 10.1002/qj.828 CrossRefGoogle Scholar
  12. Devore J L, Farnum N R, Doi J (2014) Applied statistics for engineers and scientists, 3rd. Brooks/Cole, Stamford, pp 656. ISBN-10: 113311136XGoogle Scholar
  13. Ducet N, Le Traon P, Reverdin G (2000) Global high-resolution mapping of ocean circulation from TOPEX/Poseidon and ERS-1 and-2. J Geophys Res 105(C8):19477–19498CrossRefGoogle Scholar
  14. Ebita A, Kobayashi S, Ota Y, et al (2011) The Japanese 55-year reanalysis “JRA-55”: an interim report. SOLA 7:149–152. doi: 10.2151/sola.2011-038 CrossRefGoogle Scholar
  15. Feng M (2004) Multidecadal variations of Fremantle sea level: footprint of climate variability in the tropical Pacific. Geophys Res Lett. doi: 10.1029/2004GL019947 Google Scholar
  16. Good SA, Martin MJ, Rayner NA (2013) EN4: quality controlled ocean temperature and salinity profiles and monthly objective analyses with uncertainty estimates: THE EN4 DATASET. J Geophys Res Oceans 118:6704–6716. doi: 10.1002/2013JC009067 CrossRefGoogle Scholar
  17. Han W, Meehl GA, Rajagopalan B, et al (2010) Patterns of Indian Ocean sea-level change in a warming climate. Nat Geosci 3:546–550. doi: 10.1038/ngeo901 CrossRefGoogle Scholar
  18. Han W, Meehl GA, Hu A, et al (2014a) Intensification of decadal and multi-decadal sea level variability in the western tropical Pacific during recent decades. Clim Dyn 43:1357–1379. doi: 10.1007/s00382-013-1951-1 CrossRefGoogle Scholar
  19. Han W, Vialard J, McPhaden MJ, et al (2014b) Indian Ocean decadal variability: a review. Bull Am Meteorol Soc 95:1679–1703.CrossRefGoogle Scholar
  20. Han W, Meehl GA, Stammer D, Hu A, Hamlington B, Kenigson J, Palanisamy H, Thompson P (2017) Spatial patterns of sea level variability associated with natural internal climate modes. Surv Geophys 38(1):217-250CrossRefGoogle Scholar
  21. Ishii M, Kimoto M, Sakamoto K, Iwasaki S-I (2006) Steric sea level changes estimated from historical ocean subsurface temperature and salinity analyses. J Oceanogr 62:155–170CrossRefGoogle Scholar
  22. Johnson GC, Chambers DP (2013) Ocean bottom pressure seasonal cycles and decadal trends from GRACE Release-05: Ocean circulation implications: grace seasonal cycles and decadal trends. J Geophys Res Oceans 118:4228–4240. doi: 10.1002/jgrc.20307 CrossRefGoogle Scholar
  23. Kanamitsu M, Ebisuzaki W, Woollen J, et al (2002) NCEP–DOE AMIP-II Reanalysis (R-2). Bull Am Meteorol Soc 83:1631–1643. doi: 10.1175/BAMS-83-11-1631 CrossRefGoogle Scholar
  24. Karim M, Mimura N (2008) Impacts of climate change and sea-level rise on cyclonic storm surge floods in Bangladesh. Glob Environ Change 18:490–500. doi: 10.1016/j.gloenvcha.2008.05.002 CrossRefGoogle Scholar
  25. Lee T (2004) Decadal weakening of the shallow overturning circulation in the South Indian Ocean. Geophys Res Lett. doi: 10.1029/2004GL020884 Google Scholar
  26. Lee T, McPhaden MJ (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. doi: 10.1029/2007GL032419 Google Scholar
  27. Lee, S. K., W. Park, M.O. Baringer, A.L. Gordon, B. Huber and Y. Liu (2015) Pacific origin of the abrupt increase in Indian Ocean heat content during the warming hiatus. Nat Geosci 8, 445–449.CrossRefGoogle Scholar
  28. Levitus S, Antonov JI, Boyer TP, et al (2012) World ocean heat content and thermosteric sea level change (0–2000 m), 1955–2010: WORLD OCEAN HEAT CONTENT. Geophys Res Lett 39: doi: 10.1029/2012GL051106 Google Scholar
  29. Li Y, Han W (2015) Decadal sea level variations in the Indian Ocean investigated with HYCOM: roles of climate modes, ocean internal variability, and stochastic wind forcing. J Clim 28:9143–9165. doi: 10.1175/jcli-d-15-0252.1 CrossRefGoogle Scholar
  30. Llovel W, Lee T (2015) Importance and origin of halosteric contribution to sea level change in the southeast Indian Ocean during 2005–2013: Halosteric sea level change. Geophys Res Lett 42:1148–1157. doi: 10.1002/2014GL062611 CrossRefGoogle Scholar
  31. Madec G (2015) NEMO ocean engine. Note du Pole de modélisation de l’ Institut Pierre-Simon Laplace, Paris, France, 27, 401 pp, hdl:10013/epic.46840.d001Google Scholar
  32. McPhaden MJ, Meyers G, Ando K, Masumoto Y, Murty VSN, Ravichandran M, Syamsudin F, Vialard J, Yu L, Yu W (2009) RAMA: the research moored array for African–Asian–Australian monsoon analysis and prediction. Bull Am Meteorol Soc 90:459–480CrossRefGoogle Scholar
  33. Melini D, Piersanti A (2006) Impact of global seismicity on sea level change assessment. J Geophys Res. doi: 10.1029/2004JB003476 Google Scholar
  34. Merrifield MA (2011) A shift in western tropical pacific sea level trends during the 1990s. J Clim 24:4126–4138. doi: 10.1175/2011JCLI3932.1 CrossRefGoogle Scholar
  35. Merrifield MA, Maltrud ME (2011) Regional sea level trends due to a pacific trade wind intensification: sea level and pacific trade winds. Geophys Res Lett. doi: 10.1029/2011GL049576 Google Scholar
  36. Milne GA, Gehrels WR, Hughes CW, Tamisiea ME (2009) Identifying the causes of sea-level change. Nat Geosci 2:471–478. doi: 10.1038/ngeo544 CrossRefGoogle Scholar
  37. Mitrovica JX, Tamisiea ME, Davis JL, Milne GA (2001) Recent mass balance of polar ice sheets inferred from patterns of global sea-level change. Nature 409:1026–1029CrossRefGoogle Scholar
  38. Miyama T, McCreary JP, Jensen TG, et al (2003) Structure and dynamics of the Indian-Ocean cross-equatorial cell. Deep Sea Res Part II Top Stud Oceanogr 50:2023–2047. doi: 10.1016/S0967-0645(03)00044-4 CrossRefGoogle Scholar
  39. Mogensen K, Alonso Balmaseda M, Weaver A (2012) The NEMOVAR ocean data assimilation system as implemented in the ECMWF ocean analysis for System 4. European Centre for Medium-Range Weather ForecastsGoogle Scholar
  40. Nerem RS, Chambers DP, Choe C, Mitchum GT (2010) Estimating mean sea level change from the TOPEX and jason altimeter missions. Mar Geod 33:435–446. doi: 10.1080/01490419.2010.491031 CrossRefGoogle Scholar
  41. Nidheesh AG, Lengaigne M, Vialard J, et al (2013) Decadal and long-term sea level variability in the tropical Indo-Pacific Ocean. Clim Dyn 41:381–402. doi: 10.1007/s00382-012-1463-4 CrossRefGoogle Scholar
  42. Nieves V, Willis JK, Patzert WC (2015) Recent hiatus caused by decadal shift in Indo-Pacific heating. Science 349:532–535CrossRefGoogle Scholar
  43. Praveen Kumar B, Vialard J, Lengaigne M, et al (2012) TropFlux: air-sea fluxes for the global tropical oceans—description and evaluation. Clim Dyn 38:1521–1543. doi: 10.1007/s00382-011-1115-0 CrossRefGoogle Scholar
  44. Quinn KJ, Ponte RM (2010) Uncertainty in ocean mass trends from GRACE. Geophys J Int doi: 10.1111/j.1365-246X.2010.04508.x Google Scholar
  45. Ravichandran M, BehringerD, Sivareddy S et al (2013) Evaluation of the global ocean data assimilation system at INCOIS: the tropical Indian Ocean. Ocean Model 69:123–135. doi: 10.1016/j.ocemod.2013.05.003 CrossRefGoogle Scholar
  46. Rignot E, Velicogna I, van den Broeke MR, et al (2011) Acceleration of the contribution of the Greenland and Antarctic ice sheets to sea level rise: acceleration of ice sheet loss. Geophys Res Lett. doi: 10.1029/2011GL046583 Google Scholar
  47. Roemmich D, Gilson J (2009) The 2004–2008 mean and annual cycle of temperature, salinity, and steric height in the global ocean from the Argo Program. Prog Oceanogr 82:81–100. doi: 10.1016/j.pocean.2009.03.004 CrossRefGoogle Scholar
  48. Rowley RJ, Kostelnick JC, Braaten D et al (2007) Risk of rising sea level to population and land area. Eos. Trans Am Geophys Union 88:105–107CrossRefGoogle Scholar
  49. Santer BD, Boyle JS, Hnilo JJ et al (2000) Statistical significance of trends and trend differences in layer-average atmospheric temperature time series. J Geophys Res 105:7337–7356CrossRefGoogle Scholar
  50. Schoenefeldt R, Schott FA (2006) Decadal variability of the Indian Ocean cross-equatorial exchange in SODA. Geophys Res Lett. doi: 10.1029/2006GL025891 Google Scholar
  51. Schott FA, McCreary JP (2001) The monsoon circulation of the Indian Ocean. Prog Oceanogr 51:1–123.CrossRefGoogle Scholar
  52. Schott FA, McCreary JP, Johnson GC (2004) Shallow overturning circulations of the tropical-subtropical oceans. In: Wang C, Xie S-P, Carton JA (eds) Earth climate: the ocean-atmosphere interaction, Geophys. Monogr. Ser., vol. 147. AGU, Washington, D. C, pp 261–304Google Scholar
  53. Schott FA, Xie S-P, McCreary JP (2009) Indian Ocean circulation and climate variability. Rev Geophys. doi: 10.1029/2007RG000245 Google Scholar
  54. Sivareddy S (2015) A study on global ocean analysis from an ocean data assimilation system and its sensitivity to observations and forcing fields. Ph.D. thesis, Andhra University. (Available online at
  55. Slangen AB, Lenaerts JT (2016) The sea level response to ice sheet freshwater forcing in the Community Earth System Model. Environ Res Lett 11:104002CrossRefGoogle Scholar
  56. Sprintall J, Wijffels SE, Molcard R, Jaya I (2009) Direct estimates of the Indonesian Throughflow entering the Indian Ocean: 2004–2006. J Geophys Res. doi: 10.1029/2008JC005257 Google Scholar
  57. Stammer D, Hüttemann S (2008) Response of regional sea level to atmospheric pressure loading in a climate change scenario. J Clim 21:2093–2101CrossRefGoogle Scholar
  58. Stammer D, Agarwal N, Herrmann P, Köhl A, Mechoso CR (2011) Response of a coupled ocean–atmosphere model to Greenland ice melting. Surv Geophys 32(4-5):621Google Scholar
  59. Stammer D, Cazenave A, Ponte RM, Tamisiea ME (2013) Causes for contemporary regional sea level changes. Annu Rev Mar Sci 5:21–46. doi: 10.1146/annurev-marine-121211-17240 CrossRefGoogle Scholar
  60. Thompson, P. R., et al. (2016) Forcing of recent decadal variability in the Equatorial and North Indian Ocean. J Geophys Res Oceans 121(9): 6762–6778CrossRefGoogle Scholar
  61. Timmermann A, McGregor S, Jin F-F (2010) Wind effects on past and future regional sea level trends in the southern indo-pacific. J Clim 23:4429–4437. doi: 10.1175/2010JCLI3519.1 CrossRefGoogle Scholar
  62. Trenary LL, Han W (2012) Intraseasonal-to-interannual variability of south indian ocean sea level and thermocline: remote versus local forcing. J PhysOceanogr 42:602–627. doi: 10.1175/JPO-D-11-084.1 Google Scholar
  63. Unnikrishnan AS, Nidheesh AG, Lengaigne M (2015) Sea level rise trends off the Indian coasts during the last two decades. Curr Sci 108(5): 966–971Google Scholar
  64. Vialard J (2015) Ocean science: Hiatus heat in the Indian Ocean. Nat Geosci 8(6): 423–424CrossRefGoogle Scholar
  65. Vidard A, Balmaseda M, Anderson D (2009) Assimilation of altimeter data in the ECMWF ocean analysis system 3. Mon. Weather Rev Am Meteorol Soc 137(4):1393–1408CrossRefGoogle Scholar
  66. Werner AD, Simmons CT (2009) Impact of sea-level rise on sea water intrusion in coastal aquifers. Ground Water 47:197–204. doi: 10.1111/j.1745-6584.2008.00535.x CrossRefGoogle Scholar
  67. Yu L, Weller R (2007) Objectively analyzed air–sea heat fluxes for the global ice-free Oceans (1981–2005). Bull Am Meteorol Soc 88: 527–539. doi: 10.1175/BAMS-88-4-527 CrossRefGoogle Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2017

Authors and Affiliations

  • U. Srinivasu
    • 1
  • M. Ravichandran
    • 1
    • 2
  • Weiqing Han
    • 3
  • S. Sivareddy
    • 1
  • H. Rahman
    • 1
  • Yuanlong Li
    • 3
  • Shailesh Nayak
    • 4
  1. 1.ESSO-Indian National Center for Ocean Information ServicesHyderabadIndia
  2. 2.ESSO-National Center for Antarctic and Ocean ResearchGoaIndia
  3. 3.Department of Atmospheric and Oceanic SciencesUniversity of ColoradoBoulderUSA
  4. 4.Earth System Science Organization (ESSO), Ministry of Earth SciencesNew DelhiIndia

Personalised recommendations