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Abstract:

Summer rainfall variability (October to March) shows inter-annual to multi-decadal fluctuations over a vast area of subtropical Argentina between 28°S-38°S and 65°W-70°W. Statistically significant oscillations of quasi-period in the bands of 18-21, 6, 4 and 2 years can be found throughout the region and intra-regionally, though the latter are variable. The lower frequency variation produces alternating episodes of above and below normal rainfall each lasting roughly 9 years. This quasi-fluctuation appears to be shared with the summer rainfall region of South Africa and were in-phase related one another until mid-1970s. The teleconnection between both subtropical regions could be generated by an atmospheric-oceanic bridge through the global sea surface temperatures (SSTs), particularly those of the equatorial-tropical South Atlantic. From mid-1970s, the alternating wet and dry pattern has been interrupted in the Argentine region producing the longest, as yet unfinished, wet spell of the century. Thus, a significant change of the long-term variation was observed around 1977 toward lower frequencies. Since then the statistical model that explains more than 89% of the variance of the series until 1977, diverges from the observed values in the 1980s and 1990s. In addition the Yamamoto statistical index, employed to detect a climatic jump, reaches its major value in 1973 at the beginning of the current long wet spell. Therefore the change could be located between 1973 and 1977. Application of the t-student's test gives significant differences of mean values for pre-1977 and post-1977 sub-sample from both individual time series and the regional index series. The spectral analysis also shows changes in energy bands in concordance with the features of the change that occurred from mid-1970s. The change gives rise to a significant increment of more than 20% in average of normal rainfall over the region. Conversely, a drought between mid-1980s and the 1990s has been observed in the South Africa counterpart with severe characteristics, thereby continuing the quasi-18-year oscillation. Consequently, the low-frequency coherent behaviour between both the Argentine and South Africa regions is lost from the mid-1970s. The analysis of association of wet/dry spells and warm/cold, El Nino/La Nina episodes appears to be not significant at scales of year-to-year variability although at decadal to multi-decadal scales the association could be relevant. More than one process of multi-decadal variability of global SSTs could influence the Argentine summer rainfall region and the former bidecadal teleconnection. Finally, potential hypothetical factors of change are discussed, such as the strengthening of direct and indirect mechanisms of moisture flux transport associated with global warning, low-level atmospheric circulation changes and/or to SSTs mean condition long-term variations over tropical and sub-tropical South Atlantic and South Pacific oceans.

Registro:

Documento: Artículo
Título:Climatic change and quasi-oscillations in central-west Argentina summer precipitation: Main features and coherent behaviour with southern African region
Autor:Compagnucci, R.H.; Agosta, E.A.; Vargas, W.M.
Filiación:Dept.Ciencias Atmosfera y Oceanos, Facultad Ciencias Exactas/Naturales, Universidad de Buenos Aires, Buenos Aires, CP 1428, Argentina
Palabras clave:annual variation; climate change; decadal variation; precipitation (climatology); sea surface temperature; summer; teleconnection; Africa; Argentina
Año:2002
Volumen:18
Número:5
Página de inicio:421
Página de fin:435
DOI: http://dx.doi.org/10.1007/s003820100183
Título revista:Climate Dynamics
Título revista abreviado:Clim. Dyn.
ISSN:09307575
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_09307575_v18_n5_p421_Compagnucci

Referencias:

  • Agosta, E.A., Compagnucci, R.H., Vargas, W.M., Cambios en el regimen interanual de la precipitacion estival en la region Centro-Oeste Argentina (1999) Meteorol, 24 (1-2), pp. 63-84
  • Barros, V.R., Scasso, L.M., Surface pressure and temperature anomalies in Argentina in connection with the Southern Oscillation (1994) Atmosferas, 94 (7), pp. 1159-1171
  • Barros, V.R., Castanneda, M., Doyle, M., Recent precipitation trends in Southern South America to the East of the Andes: An indication of a mode of climatic variability (1996) Greenhouse Gas emission Under Developing Countries Point of View, pp. 41-67. , Rosa LP, Santos MA (eds) COPPE, Rio de Janeiro, Brasil
  • Barros, V.R., Castaneda, M.E., Doyle, M., Recent precipitation trends in Southern South America East of the Andes: An indication of climatic variability (2000) Southern Hemisphere Paleo and Neoclimates, pp. 187-206. , Smolka PP, Volkheiner W (eds) Springer, Berlin Heidelberg New York
  • Camilloni, I., (1995) La influencia de la isla urbana de calor en las tendencias seculares de la temperatura media anual en la Argentina Subtropical, , PhD Thesis, Universidad de Buenos Aires, Argentina
  • (1996) Climatic Diagnostic Bulletin US Department of Commerce, , Climatic Analysis Center NOAA/NWS/NMC, USA
  • Compagnucci, R.H., Vargas, W.M., Spectral analysis of summer precipitation series (1983) II International Meeting on Statistical Climatology, pp. 1171-1178. , Preprints, Lisbon, Portugal, Inst Nac Meteorol Geogr (eds)
  • Compagnucci, R.H., Agosta, E.A., Vargas, M.W., Inter-annual variability of summer rainfall over Central-West Argentina (1999) 11th Conf Applied Climatology, pp. 297-300. , 10-15 January, Dallas Texas, Am Meteorol Soc (eds)
  • Ebbesmeyer, C.C., Cayan, D.R., McLain, D.R., Nichols, F.H., Peterson, D.H., Redmond, T., 1976 step in the Pacific Climate: Forty environmental changes between 1968-1975 and 1977-1984 (1991) Proc 7th Annual Pacific Climate (PACLIM) Workshop, 26, pp. 115-126. , April 1990, Betancourt JL, Tharp VL (eds) Californian Dept Water Resources, Interagency Ecological Studies Program, Tech Rep
  • Folland, C.K., Parker, D.E., Colman, A.W., Large scales modes of ocean surface temperature since the late Nineteenth Century (1999) Beyond el Nino: Decadal and Interdecadal Climate Variability, pp. 73-102. , Antonio Navarra (Ed) Springer, Berlin Heidleberg New York
  • Genta, J.L., Perez-Irabarren, G., Mechoso, C.R., A recent increasing trend in streamflow of rivers in Southeastern South America (1998) Clim, 11, pp. 2858-2862
  • Gisbson, T.T., An observed poleward shift of the Southern Hemisphere subtropical wind maximum - A greenhouse symptom? (1992) Int J Clim, 12, pp. 637-640
  • Harrison, M.S.J., (1986) A Synoptic Climatology of South African Rainfall Variations, , PhD thesis, University of the Witwater-strand, 341 pp
  • Hoel Paul, G., (1964) Introduction to Mathematical Statistics, , John Wiley, New York
  • Hoffmann, J., The continental atmospheric pressure and precipitation regime of South America (1992) Erdkunde. Archiv fur wissenschafliche geographie, pp. 40-51. , Boss, Kleve
  • Hoffmann, J., Haluszczac, G., Coy, J., Die niederschlagscharakteristk in Nordwest- und zentralargentinien und ihre wurtschaftliche bedeutung (1994) Geookodynamik, 15, pp. 151-163
  • Hurrel, J.W., van Loon, H., A modulation of the atmospheric annual cycle in the Southern Hemisphere (1994) Tellus, 46 A, pp. 325-338
  • Jenkins, G.M., Watts, D.G., (1968) Spectral Analysis and its Applications, , Holden-Day, San Francisco, 525pp
  • Kane, R.P., Trivedi, N.B., Are droughts predictable? (1986) Clim Change, 8, pp. 209-223
  • Kiladis, G.N., van Loon, H., The Southern Oscillation. Part VII: Meteorological anomalies over the Indian and Pacific sectors associated with extremes of the Oscillation (1988) Mon Weather Rev, 116, pp. 120-128
  • Kruger, A.C., The influence of the decadal-scale variability of summer rainfall on the impact of El Nino and La Nina events in South Africa (1999) Int J Clim, 19, pp. 59-68
  • Lichtenstein, E.R., (1980) La depresion del Noroeste Argentino, , PhD thesis FCEyN, University of Buenos Aires, Argentina 120p
  • Mason, S.J., Sea-surface temperature-South-African rainfall associations, 1910-1989 (1995) Int J Clim, 15, pp. 119-135
  • Mason, S.J., Rainfall trends over the lowveld of South Africa (1996) Clim Change, 32, pp. 35-54
  • Mitchell, J.M., Dzerdzeevskii, B., Flohn, H., Hofmeyr, W.L., Lamb, H.H., Rao, K.N., Wallen, C.C., Climatic change (1966) Technical Note 79, , WMO 80pp
  • Panofsky, H., Brier, G., (1958) Some Applications of Statistics to Meteorology, , College of Mineral Industries, Pennsylvania State University, 223pp
  • Penland, C., Matrosova, L., Prediction of tropical Atlantic sea surface temperature using linear inverse modelling (1998) J Clim, 11, pp. 483-496
  • Prieto, R., Gimeono, L., Garcia, R., Herrera, R., Hernandez, E., Ribera, P., Interannual variability of hail-days in the Andes region since 1885 (1999) Earth Plane Sci Lett, 171, pp. 503-509
  • Quinn, W.H., Neal, V.T., Long-term variations in the Southern Oscillation, El Nino and the Chilean subtropical rainfall (1983) Fish Bull, 81, pp. 363-374
  • Reason, C.J.C., Mulenga, H., Relationships between South African rainfall and SST anomalies in the Southwest Indean Ocean (1999) Int J Clim, 19 (15), pp. 1651-1673
  • Rasmusson, E.M., Carpenter, T.H., The relationship between Eastern equatorial Pacific sea surface temperatures and rainfall over India and Sri Lanka (1983) Mon Weather Rev, 111, pp. 516-528
  • Robertson, A.W., Mechoso, C.R., Kim, Y.-J., The influence of Atlantic sea surface temperature anomalies on North Atlantic Oscillation (2000) J. Clim Am Meteorol Soc, 13, pp. 122-138
  • Saravanan, R., Chang, P., Interaction between tropical Atlantic variability and El Nino-Southern Oscillation (2000) J. Clim, 13, pp. 2177-2194
  • Saulo, A.C., Nicolini, M., Chou, S.C., Model characterization of South American low-level flow during the 1997-1998 spring-summer season (2000) Clim Dyn, 16, pp. 867-881
  • Schwerdtfeger, W., The atmospheric circulation over Central and South America (1976) Climates of Central and South America, 12, pp. 2-12. , World Survey of Climatology, Elsevier
  • Trenberth, K.Z., Toga and atmospheric processes (1989) Understanding Climate Change Geoph Monogr 52, 7, pp. 117-125. , Berger A, Dickinson RE, Kidson JW (eds) IUGG
  • Trenberth, K.Z., Recent observed interdecadal climate changes in the Northern Hemisphere (1990) Bull Am Meteorol Soc, 71, pp. 988-993
  • Trenberth, K.Z., Atmospheric circulation climate change (1995) Clim Change, 31, pp. 427-453
  • Tyson, P.D., Dyer, T.G., The predicted above normal rainfall of the seventies and the likelihood of droughts in the eighties in South Africa (1978) S Afr J Sci, 74, pp. 372-377
  • Tyson, P.D., Atmospheric circulation variations and the occurrence of extended wet and dry spells over South Africa (1981) J. Clim, 1, pp. 115-130
  • Tyson, P.D., (1986) Climatic Change and Variability in Southern Africa, p. 220. , Oxford University Press, Cape Town
  • Tyson, P.D., Climatic changes in Southern Africa: Past and present conditions and possible future scenarios (1991) Clim Change, 18, pp. 241-258
  • Tyson, P.D., Sturman, A.P., Fitzharis, B.B., Mason, S.J., Owens, I.F., Circulation changes and teleconnections between glacial advances on the West coast of New Zealand and extended spells of drought years in South Africa (1997) Int J Clim, 17, pp. 1499-1512
  • van Loon, H., Kidson, J.W., Mullan, A.B., Decadal variation of the annual cycle in the Australian dataset (1993) J Clim, 6, pp. 1227-1231
  • Vuille, M., Bradley, R.S., Keimig, F., Climate variability in the Andes of Equator an its relation to tropical Pacific and Atlantic sea surface temperature anomalies (2000) J Clim, 13, pp. 2520-2535
  • Wang, B., Interdecadal changes in El Nino onset in the last four decades (1995) J Clim, 8, pp. 267-285
  • Wang, M., Peagle, J., Impact of analysis uncertainty upon regional atmospheric moisture flux (1996) J Geospfys Res, 101, pp. 7291-7303
  • Wright, P.B., Homogenized long-period Southern Oscillation Index (1989) Int J Climatol, 9, pp. 33-54
  • Yamamoto, R., Iwashima, Y., Sanga, T., An analysis of climatic jump (1986) J Meteorol Soc Japan, 64 (2), pp. 273-280

Citas:

---------- APA ----------
Compagnucci, R.H., Agosta, E.A. & Vargas, W.M. (2002) . Climatic change and quasi-oscillations in central-west Argentina summer precipitation: Main features and coherent behaviour with southern African region. Climate Dynamics, 18(5), 421-435.
http://dx.doi.org/10.1007/s003820100183
---------- CHICAGO ----------
Compagnucci, R.H., Agosta, E.A., Vargas, W.M. "Climatic change and quasi-oscillations in central-west Argentina summer precipitation: Main features and coherent behaviour with southern African region" . Climate Dynamics 18, no. 5 (2002) : 421-435.
http://dx.doi.org/10.1007/s003820100183
---------- MLA ----------
Compagnucci, R.H., Agosta, E.A., Vargas, W.M. "Climatic change and quasi-oscillations in central-west Argentina summer precipitation: Main features and coherent behaviour with southern African region" . Climate Dynamics, vol. 18, no. 5, 2002, pp. 421-435.
http://dx.doi.org/10.1007/s003820100183
---------- VANCOUVER ----------
Compagnucci, R.H., Agosta, E.A., Vargas, W.M. Climatic change and quasi-oscillations in central-west Argentina summer precipitation: Main features and coherent behaviour with southern African region. Clim. Dyn. 2002;18(5):421-435.
http://dx.doi.org/10.1007/s003820100183