Climate Dynamics

, Volume 45, Issue 11–12, pp 3299–3316 | Cite as

Global and European climate impacts of a slowdown of the AMOC in a high resolution GCM

  • L. C. JacksonEmail author
  • R. Kahana
  • T. Graham
  • M. A. Ringer
  • T. Woollings
  • J. V. Mecking
  • R. A. Wood


The impacts of a hypothetical slowdown in the Atlantic Meridional Overturning Circulation (AMOC) are assessed in a state-of-the-art global climate model (HadGEM3), with particular emphasis on Europe. This is the highest resolution coupled global climate model to be used to study the impacts of an AMOC slowdown so far. Many results found are consistent with previous studies and can be considered robust impacts from a large reduction or collapse of the AMOC. These include: widespread cooling throughout the North Atlantic and northern hemisphere in general; less precipitation in the northern hemisphere midlatitudes; large changes in precipitation in the tropics and a strengthening of the North Atlantic storm track. The focus on Europe, aided by the increase in resolution, has revealed previously undiscussed impacts, particularly those associated with changing atmospheric circulation patterns. Summer precipitation decreases (increases) in northern (southern) Europe and is associated with a negative summer North Atlantic Oscillation signal. Winter precipitation is also affected by the changing atmospheric circulation, with localised increases in precipitation associated with more winter storms and a strengthened winter storm track. Stronger westerly winds in winter increase the warming maritime effect while weaker westerlies in summer decrease the cooling maritime effect. In the absence of these circulation changes the cooling over Europe’s landmass would be even larger in both seasons. The general cooling and atmospheric circulation changes result in weaker peak river flows and vegetation productivity, which may raise issues of water availability and crop production.


Climate Impacts AMOC 



This work was supported by the Joint DECC/Defra Met Office Hadley Centre Climate Programme (GA01101). We would like to thank M. Mizielinski for technical assistance in setting up and running HadGEM3 and C. Mathison and K. Williams for assistance with the river flow analysis. The authors would also like to thank Pete Falloon and Richard Betts for useful discussions during the preparation of this paper. Finally we wish to thank two anonymous reviewers for their comments which improved this manuscript.


  1. Arribas A, Glover M, Maidens A, Peterson K, Gordon M, MacLachlan C, Graham R, Fereday D, Camp J, Scaife AA, Xavier P, McLean P, Colman A, Cusack S (2010) The GloSea4 ensemble prediction system for seasonal forecasting. Mon Weather Rev 139(6):1891–1910. doi: 10.1175/2010mwr3615.1 CrossRefGoogle Scholar
  2. Bernie DJ, Guilyardi E, Madec G, Slingo JM, Woolnough SJ, Cole J (2008) Impact of resolving the diurnal cycle in an ocean atmosphere GCM. Part 2: a diurnally coupled CGCM. Clim Dyn 31(7–8):909–925. doi: 10.1007/s00382-008-0429-z CrossRefGoogle Scholar
  3. Bitz CM, Lipscomb WH (1999) An energy-conserving thermodynamic model of sea ice. J Geophys Res 104(C7):15,669–15,677. doi: 10.1029/1999jc900100 CrossRefGoogle Scholar
  4. Brayshaw DJ, Woollings T, Vellinga M (2009) Tropical and extratropical responses of the North Atlantic atmospheric circulation to a sustained weakening of the MOC. J Clim 22(11):3146–3155. doi: 10.1175/2008jcli2594.1 CrossRefGoogle Scholar
  5. Bryden HL, Imawaki S (2001) Ocean heat transport. In: Siedler G, Church J, Gould J (eds) Ocean circulation and climate: observing and modelling the global ocean. Academic Press, San Fransisco, pp 455–474CrossRefGoogle Scholar
  6. Chang P, Zhang R, Hazeleger W, Wen C, Wan X, Ji L, Haarsma RJ, Breugem WP, Seidel H (2008) Oceanic link between abrupt changes in the North Atlantic Ocean and the African monsoon. Nat Geosci 1(7):444–448. doi: 10.1038/ngeo218 CrossRefGoogle Scholar
  7. Clement AC, Peterson LC (2008) Mechanisms of abrupt climate change of the last glacial period. Rev Geophys 46(4):RG4002+. doi: 10.1029/2006rg000204 CrossRefGoogle Scholar
  8. Collins M, Knutti R, Arblaster J, Dufresne JL, Fichefet T, Friedlingstein P, Gao X, Gutowski WJ, Johns T, Krinner G, Shongwe M, Tebaldi C, Weaver AJ, Wehner M (2013) Long-term climate change: projections, commitments and irreversibility. In: Stocker TF, Qin D, Plattner GK, Tignor M, Allen SK, Boschung J, Nauels A, Xia Y, Bex V, Midgley PM (eds) Climate change 2013: the physical science basis. Contribution of working group I to the fifth assessment report of the intergovernmental panel on climate change. Cambridge University Press, CambridgeGoogle Scholar
  9. Demory ME, Vidale P, Roberts M, Berrisford P, Strachan J, Schiemann R, Mizielinski M (2013) The role of horizontal resolution in simulating drivers of the global hydrological cycle. Clim Dyn 1–25: doi: 10.1007/s00382-013-1924-4
  10. de Vries P, Weber SL (2005) The Atlantic freshwater budget as a diagnostic for the existence of a stable shut down of the meridional overturning circulation. Geophys Res Lett 32:L09606. doi: 10.1029/2004GL021450 Google Scholar
  11. Drijfhout S, van Oldenborgh GJ, Cimatoribus A (2012) Is a decline of AMOC causing the warming hole above the North Atlantic in observed and modeled warming patterns? J Clim 25(24):8373–8379. doi: 10.1175/jcli-d-12-00490.1 CrossRefGoogle Scholar
  12. Falloon PD, Betts RA (2006) The impact of climate change on global river flow in HadGEM1 simulations. Atmos Sci Lett 7(3):62–68. doi: 10.1002/asl.133 CrossRefGoogle Scholar
  13. Falloon P, Betts R (2010) Climate impacts on European agriculture and water management in the context of adaptation and mitigation the importance of an integrated approach. Sci Total Environ 408(23):5667–5687. doi: 10.1016/j.scitotenv.2009.05.002 CrossRefGoogle Scholar
  14. Folland CK, Knight J, Linderholm HW, Fereday D, Ineson S, Hurrell JW (2009) The summer North Atlantic Oscillation: past, present, and future. J Clim 22(5):1082–1103. doi: 10.1175/2008jcli2459.1 CrossRefGoogle Scholar
  15. Gaspar P, Grégoris Y, Lefevre JM (1990) A simple eddy kinetic energy model for simulations of the oceanic vertical mixing: tests at station Papa and Long-Term Upper Ocean Study site. J Geophys Res 95(C9):16,179–16,193. doi: 10.1029/jc095ic09p16179 CrossRefGoogle Scholar
  16. Gastineau G, D’Andrea F, Frankignoul C (2013) Atmospheric response to the North Atlantic Ocean variability on seasonal to decadal time scales. Clim Dyn 40(9–10):2311–2330. doi: 10.1007/s00382-012-1333-0 CrossRefGoogle Scholar
  17. Gent PR, Mcwilliams JC (1990) Isopycnal mixing in ocean circulation models. J Phys Oceanogr 20(1):150–155. doi: 10.1175/1520-0485(1990)020<0150:imiocm>;2 CrossRefGoogle Scholar
  18. Good P, Lowe JA, Andrews T, Wiltshire A, Chadwick R, Ridley JK, Menary MB, Bouttes N (2015) Nonlinear regional warming with increasing CO2 concentrations. Nat Clim Chang 5.2:138–142CrossRefGoogle Scholar
  19. Hemming D, Betts R, Collins M (2013) Sensitivity and uncertainty of modelled terrestrial net primary productivity to doubled CO2 and associated climate change for a relatively large perturbed physics ensemble. Agric For Meteorol 170:79–88. doi: 10.1016/j.agrformet.2011.10.016 CrossRefGoogle Scholar
  20. Hewitt HT, Copsey D, Culverwell ID, Harris CM, Hill RSR, Keen AB, McLaren AJ, Hunke EC (2011) Design and implementation of the infrastructure of HadGEM3: the next-generation Met Office climate modelling system. Geosci Model Dev 4(2):223–253. doi: 10.5194/gmd-4-223-2011 CrossRefGoogle Scholar
  21. Hunke EC, Lipscomb WH (2010) CICE: the Los Alamos Sea Ice Model, documentation and software user’s manual. Version 4.1. Technical report LA-CC- 06-012, Los Alamos National Laboratory, Los Alamos, New Mexico. Last access 6 Feb 2014
  22. Hurkmans R, Terink W, Uijlenhoet R, Torfs P, Jacob D, Troch PA (2010) Changes in streamflow dynamics in the Rhine basin under three high-resolution regional climate scenarios. J Clim 23(3):679–699. doi: 10.1175/2009jcli3066.1 CrossRefGoogle Scholar
  23. Ineson S, Scaife AA (2009) The role of the stratosphere in the European climate response to El Nino. Nat Geosci 2(1):32–36. doi: 10.1038/ngeo381 CrossRefGoogle Scholar
  24. Jackson LC (2013) Shutdown and recovery of the AMOC in a coupled global climate model: the role of the advective feedback. Geophys Res Lett 40:1182–1188. doi: 10.1002/grl.50289 CrossRefGoogle Scholar
  25. Jacob D, Goettel H, Jungclaus J, Muskulus M, Podzun R, Marotzke J (2005) Slowdown of the thermohaline circulation causes enhanced maritime climate influence and snow cover over Europe. Geophys Res Lett 32(21):L21,711+. doi: 10.1029/2005gl023286 CrossRefGoogle Scholar
  26. Kageyama M, Merkel U, Otto-Bliesner B, Prange M, Abe-Ouchi A, Lohmann G, Roche DM, Singarayer J, Swingedouw D, Zhang X (2012) Climatic impacts of fresh water hosing under Last Glacial Maximum conditions: a multi-model study. Clim Past Discuss 8(4):3831–3869. doi: 10.5194/cpd-8-3831-2012 CrossRefGoogle Scholar
  27. Kirtman B, Bitz C, Bryan F, Collins W, Dennis J, Hearn N, Kinter J, Loft R, Rousset C, Siqueira L, Stan C, Tomas R, Vertenstein M (2012) Impact of ocean model resolution on CCSM climate simulations. Clim Dyn 39(6):1303–1328. doi: 10.1007/s00382-012-1500-3 CrossRefGoogle Scholar
  28. Klein SA, Hartmann DL (1993) The seasonal cycle of low stratiform clouds. J Clim 6(8):1587–1606. doi: 10.1175/1520-0442(1993)006<1587:tscols>;2 CrossRefGoogle Scholar
  29. Kuhlbrodt T, Rahmstorf S, Zickfeld K, Vikebø F, Sundby S, Hofmann M, Link P, Bondeau A, Cramer W, Jaeger C (2009) An integrated assessment of changes in the thermohaline circulation. Clim Change 96(4):489–537. doi: 10.1007/s10584-009-9561-y CrossRefGoogle Scholar
  30. Laurian A, Drijfhout SS, Hazeleger W, Hurk B (2010) Response of the Western European climate to a collapse of the thermohaline circulation. Clim Dyn 34(5):689–697. doi: 10.1007/s00382-008-0513-4 CrossRefGoogle Scholar
  31. Levermann A, Griesel A, Hofmann M, Montoya M, Rahmstorf S (2005) Dynamic sea level changes following changes in the thermohaline circulation. Clim Dyn 24(4):347–354. doi: 10.1007/s00382-004-0505-y CrossRefGoogle Scholar
  32. Madec G (2008) NEMO ocean engine, Note du Pole de modèlisation. France, no 27. ISSN No 1288–1619Google Scholar
  33. Manabe S, Stouffer RJ (1997) Coupled ocean–atmosphere model response to freshwater input: Comparison to Younger Dryas event. Paleoceanography 12(2):321–336. doi: 10.1029/96pa03932 CrossRefGoogle Scholar
  34. Megann A, Storkey D, Aksenov Y, Alderson S, Calvert D, Graham T, Hyder P, Siddorn J, Sinha B (2013) Go5.0: the joint NERC-Met Office NEMO global ocean model for use in coupled and forced applications. Geosci Model Dev Discuss 6(4):5747–5799. doi: 10.5194/gmdd-6-5747-2013 CrossRefGoogle Scholar
  35. Milly PCD, Dunne KA, Vecchia AV (2005) Global pattern of trends in streamflow and water availability in a changing climate. Nature 438(7066):347–350. doi: 10.1038/nature04312 CrossRefGoogle Scholar
  36. Minobe S, Kuwano-Yoshida A, Komori N, Xie SP, Small RJ (2008) Influence of the Gulf Stream on the troposphere. Nature 452(7184):206–209. doi: 10.1038/nature06690 CrossRefGoogle Scholar
  37. Parsons LA, Yin J, Overpeck JT, Stouffer RJ, Malyshev S (2014) Influence of the atlantic meridional overturning circulation on the monsoon rainfall and carbon balance of the American tropics. Geophys Res Lett 41(1):2013GL058,454+. doi: 10.1002/2013gl058454 Google Scholar
  38. Peings Y, Magnusdottir G (2014) Forcing of the wintertime atmospheric circulation by the multidecadal fluctuations of the North Atlantic ocean. Environ Res Lett 9(3):034,018+. doi: 10.1088/1748-9326/9/3/034018 CrossRefGoogle Scholar
  39. Rahmstorf S (2002) Ocean circulation and climate during the past 120,000 years. Nature 419(6903):207–214. doi: 10.1038/nature01090 CrossRefGoogle Scholar
  40. Ramankutty N, Evan AT, Monfreda C, Foley JA (2008) Farming the planet: 1. Geographic distribution of global agricultural lands in the year 2000. Glob Biogeochem Cycles 22(1):GB1003+. doi: 10.1029/2007gb002952 CrossRefGoogle Scholar
  41. Scaife AA, Copsey D, Gordon C, Harris C, Hinton T, Keeley S, O’Neill A, Roberts M, Williams K (2011) Improved Atlantic winter blocking in a climate model. Geophys Res Lett 38(23):L23,703+. doi: 10.1029/2011gl049573 Google Scholar
  42. Scaife AA, Arribas A, Blockley E, Brookshaw A, Clark RT, Dunstone N, Eade R, Fereday D, Folland CK, Gordon M, Hermanson L, Knight JR, Lea DJ, MacLachlan C, Maidens A, Martin M, Peterson AK, Smith D, Vellinga M, Wallace E, Waters J, Williams A (2014) Skillful long-range prediction of European and North American winters. Geophys Res Lett 41(7):2014GL059,637+. doi: 10.1002/2014gl059637 Google Scholar
  43. Stouffer RJ, Yin J, Gregory JM, Dixon KW, Spelman MJ, Hurlin W, Weaver AJ, Eby M, Flato GM, Hasumi H, Hu A, Jungclaus JH, Kamenkovich IV, Levermann A, Montoya M, Murakami S, Nawrath S, Oka A, Peltier WR, Robitaille DY, Sokolov A, Vettoretti G, Weber SL (2006) Investigating the causes of the response of the thermohaline circulation to past and future climate changes. J Clim 19:1365–1387CrossRefGoogle Scholar
  44. Sutton RT, Dong B (2012) Atlantic Ocean influence on a shift in European climate in the 1990s. Nat Geosci 5(11):788–792. doi: 10.1038/ngeo1595 CrossRefGoogle Scholar
  45. Swingedouw D, Rodehacke C, Behrens E, Menary M, Olsen S, Gao Y, Mikolajewicz U, Mignot J, Biastoch A (2013) Decadal fingerprints of freshwater discharge around Greenland in a multi-model ensemble. Clim Dyn 41(3–4):695–720. doi: 10.1007/s00382-012-1479-9 CrossRefGoogle Scholar
  46. Vellinga M, Wood R (2008) Impacts of thermohaline circulation shutdown in the twenty-first century. Clim Change 91(1–2):43–63. doi: 10.1007/s10584-006-9146-y CrossRefGoogle Scholar
  47. Vellinga M, Wood RA (2002) Global climatic impacts of a collapse of the Atlantic thermohaline circulation. Clim Change 54(3):251–267. doi: 10.1023/a:1016168827653 CrossRefGoogle Scholar
  48. Vellinga M, Wood RA, Gregory JM (2002) Processes governing the recovery of a perturbed thermohaline circulation in HadCM3. J Clim 15(7):764–780. doi: 10.1175/1520-0442(2002)015<0764:pgtroa>;2 CrossRefGoogle Scholar
  49. Weaver AJ, Sedláček J, Eby M, Alexander K, Crespin E, Fichefet T, Philippon-Berthier G, Joos F, Kawamiya M, Matsumoto K et al. (2012) Stability of the Atlantic meridional overturning circulation: a model intercomparison. Geophys Res Lett 39(20):L20709. doi: 10.1029/2012GL053763 Google Scholar
  50. Williams KD, Harris CM, Bodas-Salcedo A, Camp J, Comer RE, Copsey D, Fereday D, Graham T, Hill R, Hinton T, Hyder P, Ineson S, Masato G, Milton SF, Roberts MJ, Rowell DP, Sanchez C, Shelly A, Sinha B, Walters DN, West A, Woollings T, Xavier PK (2015) The Met Office Global Coupled model 2.0 (GC2) configuration. Geosci Model Dev Discuss 8(1):521–565. doi: 10.5194/gmdd-8-521-2015 CrossRefGoogle Scholar
  51. Wiltshire A, Kay G, Gornall J, Betts R (2013) The impact of climate, CO2 and population on regional food and water resources in the 2050s. Sustainability 5(5):2129–2151. doi: 10.3390/su5052129 CrossRefGoogle Scholar
  52. Woollings T, Gregory JM, Pinto JG, Reyers M, Brayshaw DJ (2012a) Response of the North Atlantic storm track to climate change shaped by ocean–atmosphere coupling. Nat Geosci 5(5):313–317. doi: 10.1038/ngeo1438 CrossRefGoogle Scholar
  53. Woollings T, Harvey B, Zahn M, Shaffrey L (2012b) On the role of the ocean in projected atmospheric stability changes in the Atlantic polar low region. Geophys Res Lett 39(24):L24,802-n/a. doi: 10.1029/2012gl054016 Google Scholar
  54. Woollings T, Franzke C, Hodson DLR, Dong B, Barnes EA, Raible CC, Pinto JG (2014) Contrasting interannual and multidecadal NAO variability. Clim Dyn 1–18. doi: 10.1007/s00382-014-2237-y
  55. Zickfeld K, Eby M, Weaver AJ (2008) Carbon-cycle feedbacks of changes in the Atlantic meridional overturning circulation under future atmospheric CO2. Glob Biogeochem Cycles 22(3):GB3024+. doi: 10.1029/2007gb003118 CrossRefGoogle Scholar

Copyright information

© Crown Copyright 2015

Authors and Affiliations

  • L. C. Jackson
    • 1
    Email author
  • R. Kahana
    • 1
  • T. Graham
    • 1
  • M. A. Ringer
    • 1
  • T. Woollings
    • 2
  • J. V. Mecking
    • 3
  • R. A. Wood
    • 1
  1. 1.Met Office Hadley CentreExeterUK
  2. 2.University of ReadingReadingUK
  3. 3.University of SouthamptonSouthamptonUK

Personalised recommendations