Theoretical and Applied Climatology

, Volume 93, Issue 1–2, pp 19–33 | Cite as

Precipitation trends in southeastern South America: relationship with ENSO phases and with low-level circulation

  • V. R. BarrosEmail author
  • M. E. Doyle
  • I. A. Camilloni


Rainfall trends in subtropical South America east of the Andes during the period 1960–1999 were studied in connection with El Niño-Southern Oscillation (ENSO) phases. In addition, monthly mean sea level pressure (SLP) fields from the National Center for Environmental Prediction reanalysis were used to look at the connection between rainfall trends and the interannual variability of the low-level atmospheric circulation. South of 22° S, annual rainfall trends were positive everywhere, and statistically significant over part of western subtropical Argentina. Over most of the region, trends resulted mostly from the warm semester (October–March) trends with little contribution from the cold semester (April–September). Under certain conditions, linear precipitation trends of each ENSO phase add up to the total rainfall trend. In northeastern Argentina, southern Brazil and Paraguay, half of the annual rainfall trend came from El Niño phase with a minor contribution from La Niña and the neutral phase. However, in most of subtropical South America, east of the Andes, precipitation trends during the extreme phases of the ENSO constitute only a small part of the trends. A Principal Component Analysis (PCA) was applied to the monthly SLP fields of the austral warm semester. The mode that advects humid air from the Atlantic Ocean over most of Argentina and Uruguay has grown at the expense of the one that favors the flow from the tropical forest over the eastern part of the continent. South of 30° S, annual rainfall trends took place predominantly during the neutral phase of the ENSO, and were related to the trends of the first two SLP leading modes. On the other hand, the annual trends were negative in the continental part of the South Atlantic Convergence Zone (SACZ), but with contributions from all ENSO phases.


Argentina Southern Oscillation Index Precipitation Trend South Atlantic Convective Zone Rainfall Trend 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Aceituno, P 1988On the functioning of the Southern Oscillation in the South American sector. Part I: Surface ClimateMon Wea Rev116505524CrossRefGoogle Scholar
  2. Barros, V, Castañeda, E, Doyle, M 2000aRecent precipitation trends in Southern South America to the east of the Andes: an indication of a mode of climatic variabilitySpringerBerlin381Google Scholar
  3. Barros, V, González, M, Liebmann, B, Camilloni, I 2000bInfluence of the South Atlantic convergence zone and South Atlantic Sea surface temperature on interannual summer rainfall variability in southeastern South AmericaTheor Appl Climatol67123133CrossRefGoogle Scholar
  4. Barros, V, Silvestri, GE 2002The relationship between sea surface temperature at the subtropical south-central Pacific and precipitation in southeastern South AmericaJ Climate15251267CrossRefGoogle Scholar
  5. Barros, V, Doyle, M, González, M, Camilloni, I, Bejarán, R, Caffera, RM 2002Revision of the South American monsoon system and climate in subtropical South America south of 20° SMeteorológica273357Google Scholar
  6. Barros V, Doyle M, Camilloni I (2005) Potential impacts of climate change in the Plata basin. Regional hydrological impacts of climate change: impact assessment and decision making. IAHS, China, 360 ppGoogle Scholar
  7. Berbery, H, Barros, V 2002The hydrological cycle of the La Plata basin in South AmericaJ Hydrometeorol3630645CrossRefGoogle Scholar
  8. Camilloni, I, Barros, V 2003Extreme discharge events in the Paraná River and their climate forcingJ Hydrol27894106CrossRefGoogle Scholar
  9. Casarin, DP, Kousky, VE 1986Anomalies de precipitacao no sul do Brasil e variacoes na circulacoes atmosféricaRev Bras Meteor18390Google Scholar
  10. Castañeda, ME, Barros, V 1994Las tendencias de la precipitación en el Cono sur de América al Este de los AndesMeteorológica192332Google Scholar
  11. Castañeda, ME, Barros, V 2001Tendencias de la precipitación en el oeste de ArgentinaMeteorológica26523Google Scholar
  12. Cazes-Boezio, G, Robertson, AW, Mechoso, CR 2003Seasonal dependence of ENSO teleconnections over South America and relationships with precipitation in UruguayJ Climate1611591176CrossRefGoogle Scholar
  13. Cressie, NAC 1991Statistics for spatial dataJohn Wiley and SonsNew York900Google Scholar
  14. Darlington, RB 1990Regression and linear modelsMcGraw-HillNew York480Google Scholar
  15. Díaz, A, Aceituno, P 2003Atmospheric circulation anomalies during episodes of enhanced and reduced convective cloudiness over UruguayJ Climate1631713185CrossRefGoogle Scholar
  16. Doyle, ME, Barros, VR 2002Midsummer low-level circulation and precipitation in subtropical South America and related sea surface temperature anomalies in the South AtlanticJ Climate1533943410CrossRefGoogle Scholar
  17. Gan, MA, Rao, VB 1991Surface cyclogenesis over South AmericaMon Wea Rev11912931302CrossRefGoogle Scholar
  18. Gandú, AW, Silva Días, PL 1998Impact of tropical heat sources on the South American tropospheric circulation and subsidenceJ Geophys Res10360016015CrossRefGoogle Scholar
  19. García, NO, Vargas, WM 1998The temporal climatic variability in the ‘Río de la Plata’ basin displayed by the river dischargesClimatic Change38359379CrossRefGoogle Scholar
  20. Garreaud, RD, Battisti, DS 1999Interanual (ENSO) and interdecadal (ENSO-like) variability in the S. HemisphereJ Climate1221132123CrossRefGoogle Scholar
  21. Genta, JL, Pérez-Iribarren, G, Mechoso, CR 1998A recent increasing trend in the streamflow of rivers in southeastern South AmericaJ Climate1128582862CrossRefGoogle Scholar
  22. Grimm, AM, de Freitas, ED, Gomes, J 1998Precipitation anomalies in southern Brazil associated with El Niño and La Niña eventsJ Climate1128632880CrossRefGoogle Scholar
  23. Grimm, AM, Barros, VR, Doyle, M 2000Climate variability in southern South America associated with El Niño and La Niña eventsJ Climate133558CrossRefGoogle Scholar
  24. IPCC2001Climate change 2001University PressCambridge881Google Scholar
  25. Kalnay, E, Kanamitsu, M, Kistler, R, Collins, W, Deaven, D, Gandin, L, Iredell, M, Sha, S, White, G, Woollen, J, Zhu, Y, Chelliah, M, Ebisuzaki, W, Higgins, W, Janowiak, J, Mo, KC, Ropelewski, C, Wang, J, Leetmaa, A, Reynolds, R, Jenne, R, Joseph, D 1996The NCEP/NCAR 40-year reanalysis projectBull Amer Meteor Soc77437471CrossRefGoogle Scholar
  26. Liebmann, B, Vera, CS, Carvalho, LMV, Camilloni, IA, Hoerling, MP, Allured, D, Barros, VR, Báez, J, Bidegain, M 2004An observed trend in central South American precipitationJ Climate1743574367CrossRefGoogle Scholar
  27. Mantua, NJ, Hare, SR, Zhang, Y, Wallace, JM, Francis, RC 1997A Pacific interdecadal climate oscillation with impacts on salmon productionBull Amer Meteor Soc7810691079CrossRefGoogle Scholar
  28. Minetti, J, Vargas, W 1998Trends and jumps in the annual precipitation in South America, south of 15° SAtmósfera11205221Google Scholar
  29. Nitta, T, Yamada, S 1989Recent warming of tropical surface temperatures and its relationship to the Northern Hemispheric circulationJ Meteor Soc Jpn67375383Google Scholar
  30. Nogués-Paegle, J, Mo, KC 1997Alternating wet and dry conditions over South America during summerMon Wea Rev125279291CrossRefGoogle Scholar
  31. Pisciottano, G, Diaz, A, Cazes, G, Mechoso, CR 1994El Niño – Southern Oscillation impact on rainfall in UruguayJ Climate712861302CrossRefGoogle Scholar
  32. Pittock, AB 1980Patterns of climatic variation in Argentina and Chile – I. Precipitation, 1931–1960Mon Wea Rev10813471361CrossRefGoogle Scholar
  33. Rao, VB, Hada, K 1990Characteristics of rainfall over Brazil: Annual variations and connections with the Southern OscillationTheor Appl Climatol428191CrossRefGoogle Scholar
  34. Ropelewski, CH, Halpert, MS 1987Global and regional scale precipitation patterns associated with the El Niño/Southern OscillationMon Wea Rev11516061626CrossRefGoogle Scholar
  35. Ropelewski, CH, Halpert, MS 1989Precipitation patterns associated with the high index phase of the Southern OscillationJ Climate2268284CrossRefGoogle Scholar
  36. Scian, B, Labraga, JC, Reimers, W, Frumento, O 2006Characteristics of large-scale atmospheric circulation related to extreme monthly rainfall anomalies in the Pampa Region, Argentina, under non-ENSO conditionsTheor Appl Climatol8589106CrossRefGoogle Scholar
  37. Seluchi, M, Saulo, CA, Nicolini, M, Satyamurti, P 2003The Northwestern Argentinean low: a study of two typical eventsMon Wea Rev13123612378CrossRefGoogle Scholar
  38. Silvestri, G 2004El Niño signal variability in the precipitation over southeastern South America during austral summerGeophys Res Lett31L18206doi: 10.1029/2004GL020590CrossRefGoogle Scholar
  39. Silvestri, G 2005Comparison between winter precipitation in southeastern South America during each ENSO phaseGeophys Res Lett32L05709doi: 10.1029/2004GL021749CrossRefGoogle Scholar
  40. Silvestri GE, Vera CS (2003) Antarctic Oscillation signal on precipitation anomalies over southeastern South America. Geophys Res Lett 30(21), doi: 10.1029/2003GL018277Google Scholar
  41. Trenberth, KE 1990Recent observed interdecadal climate changes in the Northern HemisphereBull Amer Meteor Soc74988993CrossRefGoogle Scholar
  42. Trenberth, KE 1997The definition of El NiñoBull Amer Meteor Soc7827712777CrossRefGoogle Scholar
  43. Vose RS, Schmoyer RL, Steurer PM, Peterson TC, Heim R, Karl TR, Eischeid J (1992) The Global Historical Climatology Network: long-term monthly temperature, precipitation, sea level pressure, and station pressure data. ORNL/CDIAC-53, NDP-041. Carbon Dioxide Information Analysis Center, Oak Ridge National Laboratory, Oak Ridge, TennesseeGoogle Scholar
  44. Wang, M, Paegle, J 1996Impact of analysis uncertainty upon regional atmospheric moisture fluxJ Geophys Res10172917303CrossRefGoogle Scholar
  45. Zhang, Y, Wallace, JM, Battisti, D 1997ENSO-like interdecadal variability: 1900–93J Climate1010041020CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2008

Authors and Affiliations

  1. 1.Department of Atmospheric SciencesUniversity of Buenos Aires, CIMA (CONICET-UBA)Buenos AiresArgentina

Personalised recommendations