Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul
Autor(a) principal: | |
---|---|
Data de Publicação: | 2011 |
Tipo de documento: | Dissertação |
Idioma: | por |
Título da fonte: | Manancial - Repositório Digital da UFSM |
Texto Completo: | http://repositorio.ufsm.br/handle/1/10256 |
Resumo: | An investigation of the atmospheric environments prone to severe convective weather is conducted for the subtropics of South America, east of the Andes Mountain Range. Upper air soundings valid at 00Z and 12Z for six sounding sites in subtropical South America (namely, Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG) are employed to generate a short 12-yr climatology (from January 1998 to December 2009) of some of the main necessary ingredients for severe thunderstorm development: moisture availability, conditional instability, and vertical wind shear (VWS). The goal of the climatology is to document the typical magnitudes and seasonal variability of those ingredients with the aid of convective parameters. Threshold magnitudes for such parameters were objectively determined (via quantile analysis) and tested as cut-off criteria utilized to discriminate the severe weather environments. To that end, classic North-American threshold values extracted from the literature were also tested and the results compared vis-à-vis the South-American counterparts. Distinct combinations of such thresholds were employed to select atmospheric profiles theoretically conducive to severe thunderstorms and tornadoes. Atmospheric profiles obtained from the NCEP-NCAR Reanalysis data valid at 18Z were also used. The time and space distribution of the selected severe weather profiles were examined, emphasizing the seasonal variation and geographic distribution. From these sampled profiles, composite analysis were built for and Principal Component Analysis were applied to relevant meteorological variables at distinct vertical levels in order to search for the associated synoptic-scale patterns. The climatology succesfully reproduced the expected seasonal behavior of parameters that are indicative of conditional instability and VWS. Compared to the North-American climatology, the magnitudes found for the 700-500hPa lapse rates, 0-6km bulk shear and height of the LCL were lower in South America. The seasonal variability and space distribution of the severe weather profiles suggest that there exists an equatorward [poleward] displacement of the severe weather activity as winter [summer] approaches. The synoptic pattterns associated with the severe weather environments is different from those traditionally recognized for North America, particularly at the surface. |
id |
UFSM_8d80f31be489034d43babe94f3ce182b |
---|---|
oai_identifier_str |
oai:repositorio.ufsm.br:1/10256 |
network_acronym_str |
UFSM |
network_name_str |
Manancial - Repositório Digital da UFSM |
repository_id_str |
|
spelling |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do SulAtmospheric conditions conducive to the occurrence of severe convective storms in South AmericaTeoria da convecçãoTempestades severasTornadosClimatologia sinóticaPrevisão de tempoAmérica do SulTheory of convectionSevere stormsTornadoesSynoptic climatologyWeather forecastSouth AmericaCNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::METEOROLOGIAAn investigation of the atmospheric environments prone to severe convective weather is conducted for the subtropics of South America, east of the Andes Mountain Range. Upper air soundings valid at 00Z and 12Z for six sounding sites in subtropical South America (namely, Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG) are employed to generate a short 12-yr climatology (from January 1998 to December 2009) of some of the main necessary ingredients for severe thunderstorm development: moisture availability, conditional instability, and vertical wind shear (VWS). The goal of the climatology is to document the typical magnitudes and seasonal variability of those ingredients with the aid of convective parameters. Threshold magnitudes for such parameters were objectively determined (via quantile analysis) and tested as cut-off criteria utilized to discriminate the severe weather environments. To that end, classic North-American threshold values extracted from the literature were also tested and the results compared vis-à-vis the South-American counterparts. Distinct combinations of such thresholds were employed to select atmospheric profiles theoretically conducive to severe thunderstorms and tornadoes. Atmospheric profiles obtained from the NCEP-NCAR Reanalysis data valid at 18Z were also used. The time and space distribution of the selected severe weather profiles were examined, emphasizing the seasonal variation and geographic distribution. From these sampled profiles, composite analysis were built for and Principal Component Analysis were applied to relevant meteorological variables at distinct vertical levels in order to search for the associated synoptic-scale patterns. The climatology succesfully reproduced the expected seasonal behavior of parameters that are indicative of conditional instability and VWS. Compared to the North-American climatology, the magnitudes found for the 700-500hPa lapse rates, 0-6km bulk shear and height of the LCL were lower in South America. The seasonal variability and space distribution of the severe weather profiles suggest that there exists an equatorward [poleward] displacement of the severe weather activity as winter [summer] approaches. The synoptic pattterns associated with the severe weather environments is different from those traditionally recognized for North America, particularly at the surface.Coordenação de Aperfeiçoamento de Pessoal de Nível SuperiorNeste trabalho é realizada uma investigação dos ambientes favoráveis ao desenvolvimento de convecção severa nos subtrópicos da América do Sul (AS) à leste dos Andes. Sondagens de ar superior das 00Z e 12Z de seis estações distribuídas na região subtropical da AS (quais sejam: Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG), foram utilizadas para gerar uma pequena climatologia (12 anos; de janeiro de 1998 a dezembro de 2009) de alguns dos principais ingredientes necessários para o desenvolvimento de convecção severa: oferta de umidade, instabilidade condicional termodinâmica e cisalhamento vertical do vento (CVV). A climatologia visou documentar as magnitudes típicas e a variação sazonal destes parâmetros para a região de interesse. Valores significativos dos parâmetros foram objetivamente identificados via análise de quantis e testados como limiares combinados para salientar ambientes favoráveis ao desenvolvimento de tempestades severas. Limiares para a América do Norte documentados na literatura também foram testados para este fim e confrontados com os respectivos valores da amostragem sul-americana. Diferentes combinações destes limiares foram empregadas para se extrair os perfis atmosféricos considerados teoricamente favoráveis a tempestades severas e tornados. Perfis de tempo severo também foram extraídos dos dados da Reanálise do NCEP-NCAR válidos às 18Z. Foi examinada a distribuição temporal e espacial destes ambientes de tempo severo explorando sua sazonalidade e distribuição geográfica. Partindo destes perfis, foram analisados os padrões sinóticos predominantes na região através da composição média e Análise de Componentes Principais para as variáveis meteorológicas mais relevantes em diferentes níveis verticais. A climatologia reproduziu bem o comportamento sazonal esperado dos parâmetros de instabilidade termodinâmica e CVV. Em comparação com a climatologia da América do Norte encontrou-se para a América do Sul valores mais baixos de lapse rates na média troposfera, CVV na camada entre 0-6km, e altura do NCL. A distribuição sazonal e espacial dos perfis de tempo severo sugere uma migração geográfica das condições de tempo severo das latitudes mais baixas [altas] para as latitudes mais altas [baixas] à medida que nos aproximamos dos meses de verão [inverno]. O padrão sinótico de tempo severo na América do Sul é diferente daquele tradicionalmente documentado para a América do Norte, especialmente em superfície.Universidade Federal de Santa MariaBRMeteorologiaUFSMPrograma de Pós-Graduação em MeteorologiaNascimento, Ernani de Limahttp://lattes.cnpq.br/1074092256181192Seluchi, Marcelo Enriquehttp://lattes.cnpq.br/4809059416256700Anabor, Vagnerhttp://lattes.cnpq.br/5770274675104746Foss, Marilei2011-03-162011-03-162011-02-02info:eu-repo/semantics/publishedVersioninfo:eu-repo/semantics/masterThesisapplication/pdfapplication/pdfFOSS, Marilei. ATMOSPHERIC CONDITIONS CONDUCIVE TO THE OCCURRENCE OF SEVERE CONVECTIVE STORMS IN SOUTH AMERICA. 2011. 146 f. Dissertação (Mestrado em Geociências) - Universidade Federal de Santa Maria, Santa Maria, 2011.http://repositorio.ufsm.br/handle/1/10256porinfo:eu-repo/semantics/openAccessreponame:Manancial - Repositório Digital da UFSMinstname:Universidade Federal de Santa Maria (UFSM)instacron:UFSM2022-01-07T10:41:54Zoai:repositorio.ufsm.br:1/10256Biblioteca Digital de Teses e Dissertaçõeshttps://repositorio.ufsm.br/ONGhttps://repositorio.ufsm.br/oai/requestatendimento.sib@ufsm.br||tedebc@gmail.comopendoar:2022-01-07T10:41:54Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM)false |
dc.title.none.fl_str_mv |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul Atmospheric conditions conducive to the occurrence of severe convective storms in South America |
title |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
spellingShingle |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul Foss, Marilei Teoria da convecção Tempestades severas Tornados Climatologia sinótica Previsão de tempo América do Sul Theory of convection Severe storms Tornadoes Synoptic climatology Weather forecast South America CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::METEOROLOGIA |
title_short |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
title_full |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
title_fullStr |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
title_full_unstemmed |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
title_sort |
Condições atmosféricas conducentes à ocorrência de tempestades convectivas severas na América do Sul |
author |
Foss, Marilei |
author_facet |
Foss, Marilei |
author_role |
author |
dc.contributor.none.fl_str_mv |
Nascimento, Ernani de Lima http://lattes.cnpq.br/1074092256181192 Seluchi, Marcelo Enrique http://lattes.cnpq.br/4809059416256700 Anabor, Vagner http://lattes.cnpq.br/5770274675104746 |
dc.contributor.author.fl_str_mv |
Foss, Marilei |
dc.subject.por.fl_str_mv |
Teoria da convecção Tempestades severas Tornados Climatologia sinótica Previsão de tempo América do Sul Theory of convection Severe storms Tornadoes Synoptic climatology Weather forecast South America CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::METEOROLOGIA |
topic |
Teoria da convecção Tempestades severas Tornados Climatologia sinótica Previsão de tempo América do Sul Theory of convection Severe storms Tornadoes Synoptic climatology Weather forecast South America CNPQ::CIENCIAS EXATAS E DA TERRA::GEOCIENCIAS::METEOROLOGIA |
description |
An investigation of the atmospheric environments prone to severe convective weather is conducted for the subtropics of South America, east of the Andes Mountain Range. Upper air soundings valid at 00Z and 12Z for six sounding sites in subtropical South America (namely, Porto Alegre/BRA, Florianópolis/BRA, Curitiba/BRA, Foz do Iguaçu/BRA, Resistência/ARG e Buenos Aires/ARG) are employed to generate a short 12-yr climatology (from January 1998 to December 2009) of some of the main necessary ingredients for severe thunderstorm development: moisture availability, conditional instability, and vertical wind shear (VWS). The goal of the climatology is to document the typical magnitudes and seasonal variability of those ingredients with the aid of convective parameters. Threshold magnitudes for such parameters were objectively determined (via quantile analysis) and tested as cut-off criteria utilized to discriminate the severe weather environments. To that end, classic North-American threshold values extracted from the literature were also tested and the results compared vis-à-vis the South-American counterparts. Distinct combinations of such thresholds were employed to select atmospheric profiles theoretically conducive to severe thunderstorms and tornadoes. Atmospheric profiles obtained from the NCEP-NCAR Reanalysis data valid at 18Z were also used. The time and space distribution of the selected severe weather profiles were examined, emphasizing the seasonal variation and geographic distribution. From these sampled profiles, composite analysis were built for and Principal Component Analysis were applied to relevant meteorological variables at distinct vertical levels in order to search for the associated synoptic-scale patterns. The climatology succesfully reproduced the expected seasonal behavior of parameters that are indicative of conditional instability and VWS. Compared to the North-American climatology, the magnitudes found for the 700-500hPa lapse rates, 0-6km bulk shear and height of the LCL were lower in South America. The seasonal variability and space distribution of the severe weather profiles suggest that there exists an equatorward [poleward] displacement of the severe weather activity as winter [summer] approaches. The synoptic pattterns associated with the severe weather environments is different from those traditionally recognized for North America, particularly at the surface. |
publishDate |
2011 |
dc.date.none.fl_str_mv |
2011-03-16 2011-03-16 2011-02-02 |
dc.type.status.fl_str_mv |
info:eu-repo/semantics/publishedVersion |
dc.type.driver.fl_str_mv |
info:eu-repo/semantics/masterThesis |
format |
masterThesis |
status_str |
publishedVersion |
dc.identifier.uri.fl_str_mv |
FOSS, Marilei. ATMOSPHERIC CONDITIONS CONDUCIVE TO THE OCCURRENCE OF SEVERE CONVECTIVE STORMS IN SOUTH AMERICA. 2011. 146 f. Dissertação (Mestrado em Geociências) - Universidade Federal de Santa Maria, Santa Maria, 2011. http://repositorio.ufsm.br/handle/1/10256 |
identifier_str_mv |
FOSS, Marilei. ATMOSPHERIC CONDITIONS CONDUCIVE TO THE OCCURRENCE OF SEVERE CONVECTIVE STORMS IN SOUTH AMERICA. 2011. 146 f. Dissertação (Mestrado em Geociências) - Universidade Federal de Santa Maria, Santa Maria, 2011. |
url |
http://repositorio.ufsm.br/handle/1/10256 |
dc.language.iso.fl_str_mv |
por |
language |
por |
dc.rights.driver.fl_str_mv |
info:eu-repo/semantics/openAccess |
eu_rights_str_mv |
openAccess |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Universidade Federal de Santa Maria BR Meteorologia UFSM Programa de Pós-Graduação em Meteorologia |
publisher.none.fl_str_mv |
Universidade Federal de Santa Maria BR Meteorologia UFSM Programa de Pós-Graduação em Meteorologia |
dc.source.none.fl_str_mv |
reponame:Manancial - Repositório Digital da UFSM instname:Universidade Federal de Santa Maria (UFSM) instacron:UFSM |
instname_str |
Universidade Federal de Santa Maria (UFSM) |
instacron_str |
UFSM |
institution |
UFSM |
reponame_str |
Manancial - Repositório Digital da UFSM |
collection |
Manancial - Repositório Digital da UFSM |
repository.name.fl_str_mv |
Manancial - Repositório Digital da UFSM - Universidade Federal de Santa Maria (UFSM) |
repository.mail.fl_str_mv |
atendimento.sib@ufsm.br||tedebc@gmail.com |
_version_ |
1805922070558670848 |