The nature of a heat wave in eastern Argentina occuring during SALLJEX

This note describes the physical processes associated with the occurrence of a heat wave over central Argentina during the austral summer of 2002/03, during which the South American Low-Level Jet Experiment (SALLJEX) was carried out. The SALLJEX heat wave that lasted between 25 January and 2 Februar...

Descripción completa

Guardado en:
Detalles Bibliográficos
Autores principales: Cerne, S.B., Vera, C.S., Liebmann, B.
Formato: JOUR
Materias:
Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00270644_v135_n3_p1165_Cerne
Aporte de:
id todo:paper_00270644_v135_n3_p1165_Cerne
record_format dspace
spelling todo:paper_00270644_v135_n3_p1165_Cerne2023-10-03T14:37:26Z The nature of a heat wave in eastern Argentina occuring during SALLJEX Cerne, S.B. Vera, C.S. Liebmann, B. Atmospheric movements Atmospheric temperature Climate change Statistics Tropics Weather forecasting Heat wave Intraseasonal oscillation variability Standard deviations Synoptic scale view Climatology advection air temperature anticyclone summer warming Argentina South America This note describes the physical processes associated with the occurrence of a heat wave over central Argentina during the austral summer of 2002/03, during which the South American Low-Level Jet Experiment (SALLJEX) was carried out. The SALLJEX heat wave that lasted between 25 January and 2 February 2003 was punctuated by extreme conditions during its last 3 days, with the highest temperature recorded over the last 35 yr at several stations of the region. It was found that not only the activity of synoptic-scale waves, but also the intraseasonal oscillation variability, had a strong impact on the temperature evolution during this summer. During the weeks previous to the heat wave development, an intensified South Atlantic convergence zone (SACZ) dominated the atmospheric conditions over tropical South America. Temperatures started to increase in the subtropics due to the subsidence and diabatic warming associated with the SACZ, as depicted by SALLJEX upper-air observations. An extratropical anticyclone that evolved along southern South America further intensified subsidence conditions. By the end of January the warming processes associated with SACZ activity weakened, while horizontal temperature advection began to dominate over central Argentina due to the intensification of the South American low-level jet. This mechanism led to temperature extremes by 2 February with temperature anomalies at least two standard deviations larger than the climatological mean values. Intense solar heating favored by strong subsidence was responsible for the heat wave until 31 January, after which horizontal temperature advection was the primary process associated with the temperature peak. © 2007 American Meteorological Society. JOUR info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by/2.5/ar http://hdl.handle.net/20.500.12110/paper_00270644_v135_n3_p1165_Cerne
institution Universidad de Buenos Aires
institution_str I-28
repository_str R-134
collection Biblioteca Digital - Facultad de Ciencias Exactas y Naturales (UBA)
topic Atmospheric movements
Atmospheric temperature
Climate change
Statistics
Tropics
Weather forecasting
Heat wave
Intraseasonal oscillation variability
Standard deviations
Synoptic scale view
Climatology
advection
air temperature
anticyclone
summer
warming
Argentina
South America
spellingShingle Atmospheric movements
Atmospheric temperature
Climate change
Statistics
Tropics
Weather forecasting
Heat wave
Intraseasonal oscillation variability
Standard deviations
Synoptic scale view
Climatology
advection
air temperature
anticyclone
summer
warming
Argentina
South America
Cerne, S.B.
Vera, C.S.
Liebmann, B.
The nature of a heat wave in eastern Argentina occuring during SALLJEX
topic_facet Atmospheric movements
Atmospheric temperature
Climate change
Statistics
Tropics
Weather forecasting
Heat wave
Intraseasonal oscillation variability
Standard deviations
Synoptic scale view
Climatology
advection
air temperature
anticyclone
summer
warming
Argentina
South America
description This note describes the physical processes associated with the occurrence of a heat wave over central Argentina during the austral summer of 2002/03, during which the South American Low-Level Jet Experiment (SALLJEX) was carried out. The SALLJEX heat wave that lasted between 25 January and 2 February 2003 was punctuated by extreme conditions during its last 3 days, with the highest temperature recorded over the last 35 yr at several stations of the region. It was found that not only the activity of synoptic-scale waves, but also the intraseasonal oscillation variability, had a strong impact on the temperature evolution during this summer. During the weeks previous to the heat wave development, an intensified South Atlantic convergence zone (SACZ) dominated the atmospheric conditions over tropical South America. Temperatures started to increase in the subtropics due to the subsidence and diabatic warming associated with the SACZ, as depicted by SALLJEX upper-air observations. An extratropical anticyclone that evolved along southern South America further intensified subsidence conditions. By the end of January the warming processes associated with SACZ activity weakened, while horizontal temperature advection began to dominate over central Argentina due to the intensification of the South American low-level jet. This mechanism led to temperature extremes by 2 February with temperature anomalies at least two standard deviations larger than the climatological mean values. Intense solar heating favored by strong subsidence was responsible for the heat wave until 31 January, after which horizontal temperature advection was the primary process associated with the temperature peak. © 2007 American Meteorological Society.
format JOUR
author Cerne, S.B.
Vera, C.S.
Liebmann, B.
author_facet Cerne, S.B.
Vera, C.S.
Liebmann, B.
author_sort Cerne, S.B.
title The nature of a heat wave in eastern Argentina occuring during SALLJEX
title_short The nature of a heat wave in eastern Argentina occuring during SALLJEX
title_full The nature of a heat wave in eastern Argentina occuring during SALLJEX
title_fullStr The nature of a heat wave in eastern Argentina occuring during SALLJEX
title_full_unstemmed The nature of a heat wave in eastern Argentina occuring during SALLJEX
title_sort nature of a heat wave in eastern argentina occuring during salljex
url http://hdl.handle.net/20.500.12110/paper_00270644_v135_n3_p1165_Cerne
work_keys_str_mv AT cernesb thenatureofaheatwaveineasternargentinaoccuringduringsalljex
AT veracs thenatureofaheatwaveineasternargentinaoccuringduringsalljex
AT liebmannb thenatureofaheatwaveineasternargentinaoccuringduringsalljex
AT cernesb natureofaheatwaveineasternargentinaoccuringduringsalljex
AT veracs natureofaheatwaveineasternargentinaoccuringduringsalljex
AT liebmannb natureofaheatwaveineasternargentinaoccuringduringsalljex
_version_ 1782026298270416896