Navegar

Colección

Datos Estadísticas

Artículo

Estamos trabajando para incorporar este artículo al repositorio
Consulte el artículo en la página del editor
Consulte la política de Acceso Abierto del editor

Abstract:

The South American Low-Level Jet Experiment (SALLJEX) provided a unique dataset to investigate the existence of a mesoscale low-level circulation and of a diurnal cycle in its related convergence pattern over the Southeastern South American region east of the Andes, as well as its relationship with deep convection during the warm season. The present paper builds upon high-resolution analyses produced, assimilating the data collected during the SALLJEX field campaign using BRAMS, and explores their capability to reproduce mesoscale circulations not resolved by the low density observational network available in this region. Results of the analyses show a diurnal oscillation signal in the mean boundary layer convergence pattern over the plains with a nocturnal (daytime) convergence (divergence) maximum. These results are coherent with previous findings of a nocturnal phase in the mature stage of organized deep convection and related precipitation in subtropical latitudes east of the Andes during the warm season. The diurnal cycle of convergence/divergence in the boundary layer is described over a 15-day period, during which different synoptic conditions occurred. During weakly forced environments a regime characterized by nocturnal eastward anomaly flow and convergence and daytime westward anomaly flow and divergence related to a mesoscale northwestern mountain-central plain flow regime dominates over the plains between the Andes Mountains, the Parana River Valley, and the southern Brazil mountain range. In contrast, during synoptic conditions dominated by the presence of a deep thermal low over northwestern Argentina and a related low-level jet, convergence at night is mainly accomplished by the predominantly meridional low-level jet, which exhibits an anomalous weak wind speed diurnal cycle with respect to its summer climatological mean. On the other hand daytime divergence is completely produced by the zonal wind component as in the previous synoptic situation. Mesoscale circulations are altered (still effecting mean divergence in the domain, which exhibits a diurnal oscillation) upon the initiation of deep convective circulations in the evening in an increasingly convectively unstable atmosphere driven by a persistent horizontal advection of heat and moisture at low levels and forced by convergence generated by the low-level jet and the presence of a frontal zone. Convection intensifies at night when its related convergence over the plains comes in phase with the convergence related to the nocturnal maximum in the low-level jet. © 2010 Elsevier B.V.

Registro:

Documento: Artículo
Título:Diurnal cycle in convergence patterns in the boundary layer east of the Andes and convection
Autor:Nicolini, M.; Skabar, Y.G.
Filiación:Centro de Investigaciones del Mar y la Atmósfera, CONICET, Universidad de Buenos Aires, Pab. 2, 2 Piso, Ciudad Universitaria, C1428EGA, Ciudad Autónoma, Buenos Aires, Argentina
Departamento de Ciencias de la Atmósfera y los Océanos, FCEyN, Universidad de Buenos Aires, Pab. 2, 2 Piso, Ciudad Universitaria, C1428EGA, Ciudad Autónoma, Buenos Aires, Argentina
Servicio Meteorológico Nacional. 25 de Mayo 658, C1002ABN, Ciudad Autónoma, Buenos Aires, Argentina
Facultad de Agronomía, Universidad de Buenos Aires. Av. San Martín 4453, C1417DSE, Ciudad Autónoma, Buenos Aires, Argentina
Palabras clave:Andes mountain range; Boundary layer convergence; Initiation of deep convection; Low-level jet; Mesoscale mountain-plain wind regime; Argentina; Data sets; Deep convection; Diurnal cycle; Diurnal oscillations; Field campaign; Flow regimes; Frontal zones; High resolution analysis; Horizontal advection; In-phase; Initiation of deep convection; Low density; Low level; Low level jet; Mean divergence; Mesoscale; Mesoscale circulation; Mountain ranges; Parana River; Southern Brazil; Subtropical latitudes; Synoptic conditions; Warm seasons; Wind speed; Zonal wind; Boundary layers; Natural convection; Wind; Landforms; atmospheric circulation; atmospheric convection; atmospheric forcing; atmospheric moisture; data assimilation; diurnal variation; jet; mesoscale motion; nocturnal boundary layer; wind; zonal wind; Andes
Año:2011
Volumen:100
Número:4
Página de inicio:377
Página de fin:390
DOI: http://dx.doi.org/10.1016/j.atmosres.2010.09.019
Título revista:Atmospheric Research
Título revista abreviado:Atmos. Res.
ISSN:01698095
Registro:https://bibliotecadigital.exactas.uba.ar/collection/paper/document/paper_01698095_v100_n4_p377_Nicolini

Referencias:

  • Barthlott, C., Corsmeier, U., Meißner, C., Braun, F., Kottmeier, C., The influence of mesoscale circulation systems on triggering convective cells over complex terrain (2006) Atmospheric Research, 81, pp. 150-175
  • Barthlott, C., Schipper, J.W., Kalthoff, N., Adler, B., Kottmeier, C., Blyth, A., Mobbs, S., Model representation of boundary-layer convergence triggering deep convection over complex terrain: A case study from COPS (2010) Atmospheric Research, 95, pp. 172-185
  • Blackadar, A.K., Boundary layer wind maxima and their significance for the growth of nocturnal inversions (1957) Bull. Amer. Meteor. Soc., 38, pp. 283-290
  • Borque, P., Salio, P., Nicolini, M., García Skabar, Y., Environment associated with deep moist convection under SALLJ conditions: A case study (2010) Wea. Forecasting, 25, pp. 970-984
  • Cerne, S.B., Vera, C.S., Liebmann, B., The nature of a heat wave in eastern Argentina occurring during SALLJEX (2007) Mon. Wea. Rev, 135, pp. 1165-1174
  • Cotton, W.R., Pielke, R.A., Walko, R.L., Liston, G.E., Tremback, C.J., Jiang, H., McAnelly, R.L., McFadden, J.P., RAMS 2001: Current status and future directions (2003) Meteorology and Atmospheric Physics, 82, pp. 5-29
  • Douglas, M.W., Nicolini, M., Saulo, C., Observational evidences of a low level jet east of the Andes during January-March 1998 (1998) Meteorologica, 23, pp. 63-72
  • Freitas, S.R., Longo, K.M., Dias, M.A.S., Chatfield, R., Silva Dias, P.L., Artaxo, P., Andreae, M., Panetta, J., The coupled aerosol and tracer transport model to the Brazilian developments on the regional atmospheric modeling system (CATT-BRAMS)-Part 1: Model description and evaluation (2009) Atmospheric Chemistry and Physics, 9, pp. 2843-2861
  • García Skabar, Y., Nicolini, M., Enriched analyses with assimilation of SALLJEX data (2009) J. Appl. Meteor. Climatol., 48 (12), pp. 2425-2440
  • Huffman, G.J., Adler, R.F., Bolvin, D.T., Gu, G., Nelkin, E.J., Hong, Y., Wolff, D.B., Stocker, E.F., The TRMM multisatellite analysis (TMPA): Quasiglobal multiyear, combined-sensor precipitation estimates at fine scales (2007) J. Hydrometeorol., 8, pp. 38-55
  • Kalthoff, N., Adler, B., Barthlott, C., Corsmeier, U., Mobbs, S., Crewell, S., Träumner, K., Di Girolamo, P., The impact of convergence zones on the initiation of deep convection: A case study from COPS (2009) Atmospheric Research, 93, pp. 680-694
  • Marengo, J.W., Saulo, S.A.C., Nicolini, M., Climatology of the low-level jet east of the Andes as derived from the NCEP-NCAR reanalyses: Characteristics and temporal variability (2004) Journal of Climate, 17, pp. 2261-2280
  • Nicolini, M., Paegle, J., Altinger, M.L., Numerical simulation of convection and boundary layer convergence. Preprints, Second Int. Congress of Meteorology, Buenos Aires, ArgentinaLatin Amer (1987) Meteor. Fed. Meteor. Soc., pp. 851-857
  • Nicolini, M., Saulo, A.C., Modeled Chaco low-level jets and related precipitation patterns during the 1997-1998 warm season (2006) Meteorology and Atmospheric Physics, 94, pp. 129-143
  • Nicolini, M., Salio, P., Borque, P., Thermodynamic and kinematic characterization of the low-level troposphere during SALLJEX in different large-scale environments (2006) 8th International Conference on Southern Hemisphere Meteorology and Oceanography (8ICSHMO). Foz do Iguaçu, Brazil, April 24-28, pp. 1141-1148
  • Nogués-Paegle, J., Mo, K.-C., Alternating wet and dry conditions over South America during summer (1997) Mon. Wea. Rev., 125, pp. 279-291
  • Pan, Z., Segal, M., Arritt, R.W., Role of topography in forcing low-level jets in the central United States during the 1993 flood-altered terrain simulations (2004) Mon. Wea. Rev., 132 (1), pp. 396-403
  • Salio, P., Nicolini, M., Saulo, C., Chaco low-level jet events characterization during the austral summer season (2002) Journal of Geophysical Research, 107, p. 4816
  • Salio, P., Nicolini, M., Seasonal characterization on the diurnal cycle of convection frequency over Southeastern South America under different low-jet conditions (2006) 8th International Conference on Southern Hemisphere Meteorology and Oceanography (8ICSHMO). Foz do Iguaçu, Brazil, April 24-28, pp. 1157-1162
  • Salio, P., Nicolini, M., Zipser, E.J., Mesoscale convective systems over southeastern South America and their relationship with the South American Low-Level Jet (2007) Mon. Wea. Rev, 135 (4), pp. 1290-1309
  • Saulo, C., Nicolini, M., Chou, S.C., Model characterization of the South American low-level flow during the 1997-98 spring-summer season (2000) Climate Dynamics, 16, pp. 867-881
  • Saulo, C.A., Seluchi, M., Nicolini, M., A case study of a Chaco low-level jet event (2004) Monthly Weather Review, 132, pp. 2669-2683
  • Saulo, A.C., Ferreira, L., Seluchi, M., The Northwestern Argentinean Low during SALLJEX (2005) Proceedings of CONGREMET IX (in Spanish, available at the Department of Atmospheric Sciences, Ciudad Universitaria, (1428) Buenos Aires, Argentina), 3-7 October 2005, Buenos Aires, Argentina, p. 10
  • Segal, M., Schreiber, W.E., Kallos, G., Garratt, J.R., Rodi, A., Weaver, J., Pielke, Y.R.A., The impact of crop areas in northeast Colorado on mid-summer mesoscale thermal circulations (1989) Mon. Wea. Rev, 117, pp. 809-825
  • Seluchi, M.E., Saulo, C., Nicolini, M., Satyamuyty, P., The northwestern Argentinean low: A study of two typical events (2003) Mon. Wea. Rev., 131, pp. 2361-2378
  • Seluchi, M.E., Marengo, J.A., Tropical-midlatitude exchange of air masses during summer and winter in South America: Climatic aspects and examples of intense events (2000) International Journal of Climatology, 20, pp. 1167-1190
  • Souza, E.P., Rennó, N.O., Silva Dias, M.A.F., Convective circulations induced by surface heterogeneities (2000) Journal of Atmospheric Sciences, 57, pp. 2915-2922
  • Ulanski, S.L., Garstang, M., The role of surface divergence and vorticity in the life cycle of convective rainfall-Part I: Observations and analysis (1978) J. Atmos. Sci., 35, pp. 1047-1062
  • Vera, C., The South American Low-Level Jet Experiment (2006) Bull. Amer. Meteor. Soc., 87, pp. 63-77

Citas:

---------- APA ----------
Nicolini, M. & Skabar, Y.G. (2011) . Diurnal cycle in convergence patterns in the boundary layer east of the Andes and convection. Atmospheric Research, 100(4), 377-390.
http://dx.doi.org/10.1016/j.atmosres.2010.09.019
---------- CHICAGO ----------
Nicolini, M., Skabar, Y.G. "Diurnal cycle in convergence patterns in the boundary layer east of the Andes and convection" . Atmospheric Research 100, no. 4 (2011) : 377-390.
http://dx.doi.org/10.1016/j.atmosres.2010.09.019
---------- MLA ----------
Nicolini, M., Skabar, Y.G. "Diurnal cycle in convergence patterns in the boundary layer east of the Andes and convection" . Atmospheric Research, vol. 100, no. 4, 2011, pp. 377-390.
http://dx.doi.org/10.1016/j.atmosres.2010.09.019
---------- VANCOUVER ----------
Nicolini, M., Skabar, Y.G. Diurnal cycle in convergence patterns in the boundary layer east of the Andes and convection. Atmos. Res. 2011;100(4):377-390.
http://dx.doi.org/10.1016/j.atmosres.2010.09.019