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CMIP3 projected changes in the annual cycle of the South American Monsoon

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Abstract

Nine models from the Coupled Model Intercomparison Project version 3 dataset are employed to examine projected changes in the South American Monsoon System annual cycle by comparing the 20th Century and SRES A2 scenarios. The following hypotheses are examined: (1) the warm season climate responses in the Southeast, Continental South Atlantic Convergence Zone (CSACZ) and Monsoon regions are related by regional circulation and moisture transport changes which, in turn, must be consistent with robust large-scale changes in the climate system, and (2) an increased threshold for convection in a warmer world may affect the timing of warm season rains. The present analysis reaffirms that the Southeast region is likely to experience increased precipitation through the warm season. Additional results exhibit more uncertainty due to large inter-model variance and disagreement in the A2 scenarios. Nevertheless several statistically significant results are found. In the Monsoon and to a lesser extent in the CSACZ region, the multi-model median suggests reduced precipitation during spring (Sep–Nov). These continental precipitation changes are accompanied by a southward shift of the maximum precipitation in the South Atlantic Convergence Zone. Changes in circulation include a poleward displaced South Atlantic Anticyclone (SAAC) and enhanced moisture transport associated with a strengthened northerly low level flow east of the Andes during spring. Moisture transport divergence calculations indicate unchanged divergence in the Monsoon region during spring and increased convergence in the Southeast throughout the warm season. The circulation and moisture transport changes suggest the increased precipitation in the Southeast during spring may be related to changes in the SALLJ and SAAC, which both enhance moisture transport to the Southeast. The seasonally dry Monsoon region is further affected by an increased threshold for convection in the warmer, more humid and stable climate of the 21st century, which combined with the circulation changes may weaken the onset of the rainy season. Although there is substantial variability among the models, and the results are represented by small changes compared with the multi-model variance, their statistical significance combined with their consistency with expected robust large scale changes provides a measure of confidence in otherwise tentative results. Further testing of the relationships presented here will be required to fully understand projected changes in the South American Monsoon.

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References

  • Allen MR, Stott PA, Mitchell JFB, Schnur R, Delworth TL (2000) Quantifying the uncertainty in forecasts of anthropogenic climate change. Nature 407:617–620. doi:10.1038/35036559

    Article  Google Scholar 

  • Berbery EH, Barros VR (2002) The hydrologic cycle of the La Plata basin in South America. J Hydrometeorol 3:630–645

    Article  Google Scholar 

  • Carvalho LMV, Jones C, Liebmann B (2002) Extreme precipitation in southeastern South America and large scale convective patterns in the South Atlantic convergence zone. J Climate 15:2377–2394

    Article  Google Scholar 

  • Carvalho LMV, Jones C, Liebmann B (2004) The South Atlantic Convergence Zone: intensity, form, persistence, and relationships with intraseasonal to interannual activity and extreme rainfall. J Climate 17:88–108

    Article  Google Scholar 

  • Christensen JH, Hewitson B, Busuioc A, Chen A, Gao X, Held I, Jones R, Kolli RK, Kwon WT, Laprise R, Rueda VM, Mearns L, Menéndez CG, Räisänen J, Rinke A, Sarr A, Whetton P (2007) Regional climate projections. In: Solomon S, Qin D, Manning M, Chen Z, Marquis M, Averyt K, Tignor M, Miller H (eds) Climate change 2007: the physical science basis. Contribution of working group I to the fourth assessment report of the intergovernmental panel on climate change, chap. 11. Cambridge University Press, New York, pp 235–336

    Google Scholar 

  • Cook KH, Vizy EK, Launer ZS, Patricola CM (2008) Springtime intensification of the great plains low-level jet and midwest precipitation in GCM simulations of the 21st century. J Climate. doi:10.1175/2008JCLI2355.1

    Google Scholar 

  • Diaz A, Aceituno P (2003) Atmospheric circulation anomalies during episodes of enhanced and reduced convective cloudiness over Uruguay. J Climate 16:3171–3185

    Article  Google Scholar 

  • Gan MA, Kousky VE, Ropelewski CF (2004) The South American Monsoon circulation and its relationship to rainfall over West-Central Brazil. J Climate 17:47–66

    Article  Google Scholar 

  • Gan MA, Rao VB, Moscati CL (2006) South American Monsoon indices. Atmos Sci Lett 6:219–223. doi:10.1002/asl.119

    Article  Google Scholar 

  • Giorgi F, Bi X (2005) Updated regional precipitation and temperature changes for the 21st century from ensembles of AOGCM simulations. Geophys Res Lett 33:l21715

    Article  Google Scholar 

  • Held IM, Soden BJ (2006) Robust responses of the hydrological cycle to global warming. J Climate 19:5686–5699

    Article  Google Scholar 

  • Herdies DL, da Silva A, Silva Dias MAF, Nieto Ferreira R (2002) Moisture budget of the bimodal pattern of the summer circulation over South America. J Geophys Res 107(D20):8075. doi:10.1029/2001JD000997

    Article  Google Scholar 

  • Kalnay E, Kanamitsu M, Kistler R, Collins W, Deaven D, Gandin L, Iredell M, Saha S, White G, Woollen J, Zhu Y, Leetmaa A, Reynolds B, Chelliah M, Ebisuzaki W, Higgins W, Janowiak J, Mo KC, Ropelewski C, Wang J, Jenne R, Joseph D (1996) The NCEP/NCAR 40-year reanalysis project. Bull Am Meteorol Soc 77:437–472

    Article  Google Scholar 

  • Kharin VV, Zwiers FW, Zhang X, Hegerl GC (2007) Changes in temperature and precipitation extremes in the IPCC ensemble of global coupled model simulations. J Climate 20:1419–1444

    Article  Google Scholar 

  • Kodama YM (1992) Large-scale common features of subtropical precipitation zones (the Baiu frontal zone, the SPCZ, and the SACZ). Part I: characteristics of the subtropical frontal zones. J Meteorol Soc Jpn 70:813–836

    Google Scholar 

  • Kodama YM (1993) Large-scale common features of subtropical precipitation zones (the Baiu frontal zone, the SPCZ, and the SACZ). Part II: conditions of the circulation for generating the STCZs. J Meteorol Soc Jpn 71:581–610

    Google Scholar 

  • Kousky VE, Kagano MT, Cavalcanti IFA (1984) A review of the Southern Oscillation: oceanic-atmospheric circulation changes and related rainfall anomalies. Tellus Series A 36:490

    Article  Google Scholar 

  • Li W, Fu R, Dickinson RE (2006) Rainfall and its seasonality over the Amazon in the 21st century as assessed by the coupled models for the IPCC AR4. J Geophys Res 111:D02111. doi:10.1029/2005JD006355

    Article  Google Scholar 

  • Liebmann B, Vera CS, Carvalho LMV, Camilloni IA, Hoerling MP, Allured D, Barros VR, Báez J, Bidegain M (2004) An observed trend in Central South American precipitation. J Climate 17:4357–4367

    Article  Google Scholar 

  • Lintner BR, Neelin JD (2006) A prototype for convective margin shifts. Geophys Res Lett 34. doi:10.1029/2006GL027305

    Google Scholar 

  • Marengo J (1992) Interannual variability of surface climate in the Amazon basin. Int J Climatol 12:853–863

    Article  Google Scholar 

  • Marengo JA, Douglas M, Silva Dias P (2002) The South American low level jet East of the Andes during LBA-TRMM and WET AMC campaign of January–April 1999. J Geophys Res 107(47):1–11

    Google Scholar 

  • Marengo JA, Soares WR, Saulo C, Nicolini M (2004) Climatology of the low level jet East of the Andes as derived from NCEP-NCAR reanalyses: characteristics of temporal variability. J Climate 17(12):2261–2280

    Article  Google Scholar 

  • Meehl GA, Covey C, Delworth T, Mojib L, McAvaney B, Mitchell JFB, Stouffer RJ, Taylor KE (2007) The WCRP CMIP3 multimodel dataset: a new era in climate change research. Bull Am Meteorol Soc 88:1383–1394

    Article  Google Scholar 

  • Neelin JD, Chou C, Su H (2003) Tropical drought regions in global warming and El Niño teleconnections. Geophys Res Lett 30(24):2275. doi:10.1029/2003GL018625

    Article  Google Scholar 

  • Nogués-Paegle J, Mo KC (1997) Alternating wet and dry conditions over South America during summer. Mon Weather Rev 125:279–291

    Article  Google Scholar 

  • Paegle J (1998) A comparative review of South American low-level jets. Meteorologica 23:73–81

    Google Scholar 

  • Rauscher SA, Giorgi F, Diffenbaugh NS, Seth A (2008) Extension and intesification of the Meso-American mid-summer drought in the twenty-first century. Clim Dyn 31:551–571. doi:10.1007/s00382-007-0359-1

    Article  Google Scholar 

  • Ropelewski CF, Halpert MS (1987) Global and regional scale precipitation patterns associated with the El Niño Southern Oscillation. Mon Weather Rev 115:1606–1626

    Article  Google Scholar 

  • Solomon S, Qin D (2007) Climate change 2007: the physical science basis. In: Working group I report to the fourth assessment of the Intergovernmental Panel on Climate Change (IPCC). Cambridge University Press, Cambridge

    Google Scholar 

  • Vecchi GA, Soden BJ (2007) Global warming and the weakening of the tropical circulation. J Climate 20:4316–4340

    Article  Google Scholar 

  • Vera C, Baez J, Douglas M, Emmanuel CB, Marengo J, Meitin J, Nicolini M, Nogues-Paegle J, Paegle J, Penalba O, Salio P, Saulo C, Silva Dias MA, Silva Dias P, Zipser E (2006a) The South American low-level jet experiment. Bull Am Meteorol Soc 87:63–77

    Article  Google Scholar 

  • Vera C, Higgins W, Amador J, Ambrizzi T, Garreaud R, Gochis D, Gutzler D, Lettenmaier D, Marengo J, Nogues-Paegle J, Silva Dias P, Zhang C (2006b) Toward a unified view of the American monsoon systems. J Climate 19:4977–5000

    Article  Google Scholar 

  • Vera C, Silvestri G, Liebmann B, Gonzalez P (2006c) Climate change scenarios for seasonal precipitation in South America from IPCC-AR4 models. Geophys Res Lett 33. doi:10.1029/2006GL025759

    Google Scholar 

  • Virji H (1981) A preliminary study of summertime tropospheric circulation patterns over South America estimated from cloud winds. Mon Weather Rev 109:599–610

    Article  Google Scholar 

  • Wilks DS (2005) Statistical methods in the atmospheric sciences, vol 91, 2nd edn. Academic, London

    Google Scholar 

  • Xie P, Arkin P (1996) Analysis of global monthly precipitation using gauge observation, satellite estimates and numerical model predictions. J Climate 9:840–858

    Article  Google Scholar 

  • Yin JH (2005) A consistent poleward shift of the storm tracks in simulations of 21st century climate. Geophys Res Lett 32:L18701. doi:10.1029/2005GL023684

    Article  Google Scholar 

  • Zhou J, Lau KM (1998) Does a monsoon climate exist over South America? J Climate 11:1020–1040

    Article  Google Scholar 

Download references

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Correspondence to Anji Seth.

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Seth, A., Rojas, M. & Rauscher, S.A. CMIP3 projected changes in the annual cycle of the South American Monsoon. Climatic Change 98, 331–357 (2010). https://doi.org/10.1007/s10584-009-9736-6

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  • DOI: https://doi.org/10.1007/s10584-009-9736-6

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