The Rapid Warming of the North Atlantic Ocean in the Mid-1990s in an Eddy-Permitting Ocean Reanalysis (1982–2013)

Chunxue Yang Centro Euro-Mediterraneo per i Cambiamenti Climatici, Bologna, Italy

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Simona Masina Centro Euro-Mediterraneo per i Cambiamenti Climatici, and Istituto Nazionale di Geofisica e Vulcanologia, Bologna, Italy

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Alessio Bellucci Centro Euro-Mediterraneo per i Cambiamenti Climatici, Bologna, Italy

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Andrea Storto Centro Euro-Mediterraneo per i Cambiamenti Climatici, Bologna, Italy

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Abstract

The rapid warming in the mid-1990s in the North Atlantic Ocean is investigated by means of an eddy-permitting ocean reanalysis. Both the mean state and variability, including the mid-1990s warming event, are well captured by the reanalysis. An ocean heat budget applied to the subpolar gyre (SPG) region (50°–66°N, 60°–10°W) shows that the 1995–99 rapid warming is primarily dictated by changes in the heat transport convergence term while the surface heat fluxes appear to play a minor role. The mean negative temperature increment suggests a warm bias in the model and data assimilation corrects the mean state of the model, but it is not crucial to reconstruct the time variability of the upper-ocean temperature. The decomposition of the heat transport across the southern edge of the SPG into time-mean and time-varying components shows that the SPG warming is mainly associated with both the anomalous advection of mean temperature and the mean advection of temperature anomalies across the 50°N zonal section. The relative contributions of the Atlantic meridional overturning circulation (AMOC) and gyre circulation to the heat transport are also analyzed. It is shown that both the overturning and gyre components are relevant to the mid-1990s warming. In particular, the fast adjustment of the barotropic circulation response to the NAO drives the anomalous transport of mean temperature at the subtropical/subpolar boundary, while the slowly evolving AMOC feeds the large-scale advection of thermal anomalies across 50°N. The persistently positive phase of the NAO during the years prior to the rapid warming likely favored the cross-gyre heat transfer and the following SPG warming.

Corresponding author address: Chunxue Yang, Centro Euro-Mediterraneo per i Cambiamenti Climatici, Via M. Franceschini, 31, Bologna 40128, Italy. E-mail: chunxue.yang@cmcc.it

Abstract

The rapid warming in the mid-1990s in the North Atlantic Ocean is investigated by means of an eddy-permitting ocean reanalysis. Both the mean state and variability, including the mid-1990s warming event, are well captured by the reanalysis. An ocean heat budget applied to the subpolar gyre (SPG) region (50°–66°N, 60°–10°W) shows that the 1995–99 rapid warming is primarily dictated by changes in the heat transport convergence term while the surface heat fluxes appear to play a minor role. The mean negative temperature increment suggests a warm bias in the model and data assimilation corrects the mean state of the model, but it is not crucial to reconstruct the time variability of the upper-ocean temperature. The decomposition of the heat transport across the southern edge of the SPG into time-mean and time-varying components shows that the SPG warming is mainly associated with both the anomalous advection of mean temperature and the mean advection of temperature anomalies across the 50°N zonal section. The relative contributions of the Atlantic meridional overturning circulation (AMOC) and gyre circulation to the heat transport are also analyzed. It is shown that both the overturning and gyre components are relevant to the mid-1990s warming. In particular, the fast adjustment of the barotropic circulation response to the NAO drives the anomalous transport of mean temperature at the subtropical/subpolar boundary, while the slowly evolving AMOC feeds the large-scale advection of thermal anomalies across 50°N. The persistently positive phase of the NAO during the years prior to the rapid warming likely favored the cross-gyre heat transfer and the following SPG warming.

Corresponding author address: Chunxue Yang, Centro Euro-Mediterraneo per i Cambiamenti Climatici, Via M. Franceschini, 31, Bologna 40128, Italy. E-mail: chunxue.yang@cmcc.it
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  • Barnier, B., and Coauthors, 2006: Impact of partial steps and momentum advection schemes in a global ocean circulation model at eddy-permitting resolution. Ocean Dyn., 56, 543567, doi:10.1007/s10236-006-0082-1.

    • Search Google Scholar
    • Export Citation
  • Barrier, N., C. Cassou, J. Deshayes, and A.-M. Treguier, 2014: Response of North Atlantic ocean circulation to atmospheric weather regimes. J. Phys. Oceanogr., 44, 179201, doi:10.1175/JPO-D-12-0217.1.

    • Search Google Scholar
    • Export Citation
  • Barrier, N., J. Deshayes, A. Treguier, and C. Cassou, 2015: Heat budget in the North Atlantic subpolar gyre: Impacts of atmospheric weather regimes on the 1995 warming event. Prog. Oceanogr., 130, 7590, doi:10.1016/j.pocean.2014.10.001.

    • Search Google Scholar
    • Export Citation
  • Bellucci, A., and K. J. Richards, 2006: Effects of NAO variability on the North Atlantic Ocean circulation. Geophys. Res. Lett., 33, L02612, doi:10.1029/2005GL024890.

    • Search Google Scholar
    • Export Citation
  • Bellucci, A., S. Gualdi, E. Scoccimarro, and A. Navarra, 2008: NAO–ocean interactions in a coupled general circulation model. Climate Dyn., 31, 759777, doi:10.1007/s00382-008-0408-4.

    • Search Google Scholar
    • Export Citation
  • Bersch, M., I. Yashayaev, and K. P. Koltermann, 2007: Recent changes of the thermohaline circulation in the subpolar North Atlantic. Ocean Dyn., 57, 223235, doi:10.1007/s10236-007-0104-7.

    • Search Google Scholar
    • Export Citation
  • Brauch, J. P., and R. Gerdes, 2005: Response of the northern North Atlantic and Arctic Oceans to a sudden change of the North Atlantic Oscillation. J. Geophys. Res., 110, C11018, doi:10.1029/2004JC002436.

    • Search Google Scholar
    • Export Citation
  • Bryden, H. L., and S. Imawaki, 2001: Ocean heat transport. Ocean Circulation and Climate, G. Siedler, J. Church, and J. Gould, Eds., International Geophysics Series, Vol. 77, Academic Press, 453–521.

  • Cavalieri, D., D. Parkinson, P. Gloersen, and H. J. Zwally, 1996: Sea ice concentrations from Nimbus-7 SMMR and DMSP SSM/I-SSMIS passive microwave data, version 1. NASA National Snow and Ice Data Center DAAC, 14 December 2014, doi:10.5067/8GQ8LZQVL0VL.

  • Cessi, P., N. Pinardi, and V. Lyubartsev, 2014: Energetics of semienclosed basins with two-layer flows at the Strait. J. Phys. Oceanogr., 44, 967979, doi:10.1175/JPO-D-13-0129.1.

    • Search Google Scholar
    • Export Citation
  • Dai, A., and K. E. Trenberth, 2002: Estimates of freshwater discharge from continents: Latitudinal and seasonal variations. J. Hydrometeor., 3, 660687, doi:10.1175/1525-7541(2002)003<0660:EOFDFC>2.0.CO;2.

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

    • Search Google Scholar
    • Export Citation
  • Desbruyères, D., H. Mercier, and V. Thierry, 2014: On the mechanisms behind decadal heat content changes in the eastern subpolar gyre. Prog. Oceanogr., 132, 262272, doi:10.1016/j.pocean.2014.02.005.

    • Search Google Scholar
    • Export Citation
  • Dommenget, D., and M. Latif, 2000: Interannual to decadal variability in the tropical Atlantic. J. Climate, 13, 777792, doi:10.1175/1520-0442(2000)013<0777:ITDVIT>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Dong, B., and R. T. Sutton, 2002: Variability in North Atlantic heat content and heat transport in a coupled ocean–atmosphere GCM. Climate Dyn., 19, 485497, doi:10.1007/s00382-002-0239-7.

    • Search Google Scholar
    • Export Citation
  • Dussin, R., and B. Barnier, 2013: The making of DFS5.1. Drakkar Project Rep., LGGE, 40 pp.

  • Eden, D., and J. Willebrand, 2001: Mechanism of interannual to decadal variability of the North Atlantic circulation. J. Climate, 14, 22662280, doi:10.1175/1520-0442(2001)014<2266:MOITDV>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Ezer, T., 2015: Detecting changes in the transport of the Gulf Stream and the Atlantic overturning circulation from coastal sea level data: The extreme decline in 2009–2010 and estimated variations for 1935–2012. Global Planet. Change, 129, 2326, doi:10.1016/j.gloplacha.2015.03.002.

    • Search Google Scholar
    • Export Citation
  • Fichefet, T., and M. A. Morales Maqueda, 1997: Sensitivity of a global sea ice model to the treatment of ice thermodynamics and dynamics. J. Geophys. Res., 102, 12 60912 646, doi:10.1029/97JC00480.

    • Search Google Scholar
    • Export Citation
  • Good, S. A., M. J. Martin, and N. A. Rayner, 2013: EN4: Quality controlled ocean temperature and salinity profiles and monthly objective analyses with uncertainty estimates. J. Geophys. Res. Oceans, 118, 67046716, doi:10.1002/2013JC009067.

    • Search Google Scholar
    • Export Citation
  • Grist, J. P., and Coauthors, 2010: The roles of surface heat flux and ocean heat transport convergence in determining Atlantic Ocean temperature variability. Ocean Dyn., 60, 771790, doi:10.1007/s10236-010-0292-4.

    • Search Google Scholar
    • Export Citation
  • Häkkinen, S., and P. B. Rhines, 2004: Decline of subpolar North Atlantic circulation during the 1990s. Science, 304, 555559, doi:10.1126/science.1094917.

    • Search Google Scholar
    • Export Citation
  • Häkkinen, S., P. B. Rhines, and D. L. Worthen, 2011: Warm and saline events embedded in the meridional circulation of the northern North Atlantic. J. Geophys. Res., 116, C03006, doi:10.1029/2010JC006275.

    • Search Google Scholar
    • Export Citation
  • Hátún, H., A. B. Sando, H. Drange, B. Hansen, and H. Valdimarsson, 2005: Influence of the Atlantic subpolar gyre on the thermohaline circulation. Science, 309, 18411844, doi:10.1126/science.1114777.

    • Search Google Scholar
    • Export Citation
  • Hátún, H., M. R. Payne, and J. A. Jacobsen, 2009: The North Atlantic subpolar gyre regulates the spawning distribution of blue whiting (Micromesistius poutassou). Can. J. Fish. Aquat. Sci., 66, 759770, doi:10.1139/F09-037.

    • Search Google Scholar
    • Export Citation
  • Herbaut, C., and M. N. Houssais, 2009: Response of the eastern North Atlantic subpolar gyre to the North Atlantic Oscillation. Geophys. Res. Lett., 36, L17607, doi:10.1029/2009GL039090.

    • Search Google Scholar
    • Export Citation
  • Holland, D. M., R. H. Thomas, B. de Young, M. H. Ribergaard, and B. Lyberth, 2008: Acceleration of Jakobshavn Isbrae triggered by warm subsurface ocean waters. Nat. Geosci., 1, 659664, doi:10.1038/ngeo316.

    • Search Google Scholar
    • Export Citation
  • Hurrell, J. W., and C. Deser, 2010: North Atlantic climate variability: The role of the North Atlantic Oscillation. J. Mar. Syst., 79, 231244, doi:10.1016/j.jmarsys.2009.11.002.

    • Search Google Scholar
    • Export Citation
  • Ingleby, B., and M. Huddleston, 2007: Quality control of ocean temperature and salinity profiles—historical and real-time data. J. Mar. Syst., 65, 158175, doi:10.1016/j.jmarsys.2005.11.019.

    • Search Google Scholar
    • Export Citation
  • Kushnir, Y., 1994: Interdecadal variations in North Atlantic sea surface temperature and associated atmospheric conditions. J. Climate, 7, 141157, doi:10.1175/1520-0442(1994)007<0141:IVINAS>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Kwon, Y., and C. Frankignoul, 2012: Stochastically driven multidecadal variability of the Atlantic meridional overturning circulation in CCSM3. Climate Dyn., 38, 859876, doi:10.1007/s00382-011-1040-2.

    • Search Google Scholar
    • Export Citation
  • Large, W. G., and S. G. Yeager, 2004: Diurnal to decadal global forcing for ocean and sea ice models: The data sets and flux climatologies. NCAR Tech. Note NCAR/TN-460+STR, 105 pp.

  • Lohmann, K., H. Drange, and M. Bentsen, 2009a: Response of the North Atlantic subpolar gyre to persistent North Atlantic Oscillation like forcing. Climate Dyn., 32, 273285, doi:10.1007/s00382-008-0467-6.

    • Search Google Scholar
    • Export Citation
  • Lohmann, K., H. Drange, and M. Bentsen, 2009b: A possible mechanism for the strong weakening of the North Atlantic subpolar gyre in the mid-1990s. Geophys. Res. Lett., 36, L15602, doi:10.1029/2009GL039166.

    • Search Google Scholar
    • Export Citation
  • Madec, G., P. Delecluse, M. Imbard, and C. Levy, 1998: OPA 8 ocean general circulation model—reference manual. IPSL Laboratoire d’Océanographie Dynamique et de Climatologie Tech. Note 11, 91 pp.

  • Marsh, R., S. A. Josey, B. A. de Cuevas, L. J. Redbourn, and G. D. Quartly, 2008: Mechanisms for recent warming of the North Atlantic: Insights gained with an eddy-permitting model. J. Geophys. Res., 113, C04031, doi:10.1029/2007JC004096.

    • Search Google Scholar
    • Export Citation
  • Marshall, J., H. Johnson, and J. Goodman, 2001: A study of the interaction of the North Atlantic Oscillation with ocean circulation. J. Climate, 14, 13991421, doi:10.1175/1520-0442(2001)014<1399:ASOTIO>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • McCarthy, G. D., and Coauthors, 2015: Measuring the Atlantic meridional overturning circulation at 26°N. Prog. Oceanogr., 130, 91111, doi:10.1016/j.pocean.2014.10.006.

    • Search Google Scholar
    • Export Citation
  • McGregor, S., A. Timmermann, M. F. Stuecker, M. H. England, M. Merrifield, F.-F. Jin, and Y. Chikamoto, 2014: Recent walker circulation strengthening and Pacific cooling amplified by Atlantic warming. Nat. Climate Change, 4, 888892, doi:10.1038/nclimate2330.

    • Search Google Scholar
    • Export Citation
  • Msadek, R., and Coauthors, 2014: Predicting a decadal shift in North Atlantic climate variability using the GFDL forecast system. J. Climate, 27, 64726496, doi:10.1175/JCLI-D-13-00476.1.

    • Search Google Scholar
    • Export Citation
  • Pickart, R. S., D. J. Torres, and R. A. Clarke, 2002: Hydrography of the Labrador Sea during active convection. J. Phys. Oceanogr., 32, 428457, doi:10.1175/1520-0485(2002)032<0428:HOTLSD>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Reynolds, R. W., T. M. Smith, C. Liu, D. B. Chelton, K. S. Casey, and M. G. Schlax, 2007: Daily high-resolution blended analyses for sea surface temperature. J. Climate, 20, 54735496, doi:10.1175/2007JCLI1824.1.

    • Search Google Scholar
    • Export Citation
  • Robson, J. I., R. Sutton, K. Lohmann, D. Smith, and M. D. Palmer, 2012a: Causes of the rapid warming of the North Atlantic Ocean in the mid-1990s. J. Climate, 25, 41164134, doi:10.1175/JCLI-D-11-00443.1.

    • Search Google Scholar
    • Export Citation
  • Robson, J. I., R. Sutton, and D. M. Smith, 2012b: Initialized decadal predictions of the rapid warming of the North Atlantic Ocean in the mid 1990s. Geophys. Res. Lett., 39, L19713, doi:10.1029/2012GL053370.

    • Search Google Scholar
    • Export Citation
  • Sarafanov, A., A. Falina, A. Solov, and A. Demidov, 2008: Intense warming and salinification of intermediate waters of southern origin in the eastern subpolar North Atlantic in the 1990s to mid-2000s. J. Geophys. Res., 113, C12022, doi:10.1029/2008JC004975.

    • Search Google Scholar
    • Export Citation
  • Smith, D. M., R. Eade, N. J. Dunstone, D. Fereday, J. M. Murphy, H. Pohlmann, and A. A. Scife, 2010: Skilful multi-year predictions of Atlantic hurricane frequency. Nat. Geosci., 3, 846849, doi:10.1038/ngeo1004.

    • Search Google Scholar
    • Export Citation
  • Storto, A., S. Dobricic, S. Masina, and P. Di Pietro, 2011: Assimilating along-track altimetric observations through local hydrostatic adjustments in a global ocean reanalysis system. Mon. Wea. Rev., 139, 738754, doi:10.1175/2010MWR3350.1.

    • Search Google Scholar
    • Export Citation
  • Storto, A., S. Masina, and S. Dobricic, 2014: Estimation and impact of nonuniform horizontal correlation length scales for global ocean physical analyses. J. Atmos. Oceanic Technol., 31, 23302349, doi:10.1175/JTECH-D-14-00042.1.

    • Search Google Scholar
    • Export Citation
  • Storto, A., S. Masina, and A. Navarra, 2015: Evaluation of the CMCC eddy-permitting global ocean physical reanalysis system (C-GLORS, 1982–2012) and its assimilation. Quart. J. Roy. Meteor. Soc., 142, 738758, doi:10.1002/qj.2673.

    • Search Google Scholar
    • Export Citation
  • Storto, A., and Coauthors, 2016: Steric sea level variability (1993–2010) in an ensemble of ocean reanalyses and objective analyses. Climate Dyn., doi:10.1007/s00382-015-2554-9, in press.

    • Search Google Scholar
    • Export Citation
  • Sutton, R. T., and D. L. R. Hodson, 2003: Influence of the ocean on North Atlantic climate variability 1871–1999. J. Climate, 16, 32963313, doi:10.1175/1520-0442(2003)016<3296:IOTOON>2.0.CO;2.

    • Search Google Scholar
    • Export Citation
  • Sutton, R. T., and D. L. R. Hodson, 2005: Atlantic Ocean forcing of North American and European summer climate. Science, 309, 115118, doi:10.1126/science.1109496.

    • Search Google Scholar
    • Export Citation
  • Sutton, R. T., and B. Dong, 2012: Atlantic Ocean influence on a shift in European climate in the 1990s. Nat. Geosci., 5, 788792, doi:10.1038/ngeo1595.

    • Search Google Scholar
    • Export Citation
  • Thierry, V., E. de Boisséson, and H. Mercier, 2008: Interannual variability of the subpolar mode water properties over the Reykjanes ridge during 1990–2006. J. Geophys. Res., 113, C04016, doi:10.1029/2007JC004443.

    • Search Google Scholar
    • Export Citation
  • Ting, M., Y. Kushnir, R. Seager, and C. Li, 2009: Forced and internal twentieth-century SST trends in the North Atlantic. J. Climate, 22, 14691481, doi:10.1175/2008JCLI2561.1.

    • Search Google Scholar
    • Export Citation
  • Visbeck, M., E. Chassignet, R. Curry, T. Delworth, B. Dickson, and G. Krahmann, 2003: The ocean’s response to North Atlantic Oscillation variability. The North Atlantic Oscillation: Cinematic Significance and Environmental Impact, Geophys. Monogr., Vol. 134, Amer. Geophys. Union, 113–146.

  • Wijffels, S. E., J. Willis, C. M. Domingues, P. Barker, N. J. White, A. Gronell, K. Ridgway, and J. A. Church, 2008: Changing expendable bathythermograph fall rates and their impact on estimates of thermosteric sea level rise. J. Climate, 21, 56575672, doi:10.1175/2008JCLI2290.1.

    • Search Google Scholar
    • Export Citation
  • Yeager, S., A. Karspeck, G. Danabasoglu, J. Tribbia, and H. Teng, 2012: A decadal prediction case study: Late twentieth-century North Atlantic Ocean heat content. J. Climate, 25, 51735189, doi:10.1175/JCLI-D-11-00595.1.

    • Search Google Scholar
    • Export Citation
  • Zalesak, S. T., 1979: Fully multidimensional flux corrected transport algorithms for fluids. J. Comput. Phys., 31, 335362, doi:10.1016/0021-9991(79)90051-2.

    • Search Google Scholar
    • Export Citation
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