@MastersThesis{Tavares:2008:EsObIn,
author = "Tavares, Priscila da Silva",
title = "Um estudo observacional da incurs{\~a}o de sistemas frontais no
nordeste brasileiro e sua influ{\^e}ncia na atmosfera do Centro
de Lan{\c{c}}amento de Alc{\^a}ntara (CLA)",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2008",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2008-04-03",
keywords = "sistemas frontais, Centro de Lan{\c{c}}amento de Alc{\^a}ntara
(CLA), observacional, climatologia, frontal systems, Alcantara
Lauching Center (ALC), observational, climatology.",
abstract = "Neste trabalho, realizou-se um estudo observacional do padr{\~a}o
sin{\'o}tico configurado, sobre a Am{\'e}rica do Sul (AS) e os
Oceanos Atl{\^a}ntico Sul (OAS) e Pac{\'{\i}}fico Sul (OPS), em
eventos de SFs que atingiram o litoral do Nordeste Brasileiro
(NEB), em latitudes ao norte 17°S, e provocaram intensa
nebulosidade na regi{\~a}o do Centro de Lan{\c{c}}amento de
Alc{\^a}ntara (CLA). Selecionaram-se sete eventos para
an{\'a}lise sin{\'o}tica, os quais abrangeram todas as
esta{\c{c}}{\~o}es do ano. Estes foram analisados desde a sua
incurs{\~a}o no sul do Brasil at{\'e} sua m{\'a}xima
incurs{\~a}o no pa{\'{\i}}s, buscando identificar os
poss{\'{\i}}veis mecanismos sin{\'o}ticos que favoreceram os
seus deslocamentos. Em seguida, investigou-se a influ{\^e}ncia do
SF, na atmosfera do CLA, atrav{\'e}s da an{\'a}lise dos
par{\^a}metros meteorol{\'o}gicos de superf{\'{\i}}cie. Da
an{\'a}lise sin{\'o}tica, verificou-se a ocorr{\^e}ncia de
ciclog{\^e}nese {\`a} superf{\'{\i}}cie, geralmente ocorrida
na costa leste do Rio Grande do Sul. Sobre os OPS e OAS,
observaram-se valores de PNM na regi{\~a}o da Alta Subtropical do
Pac{\'{\i}}fico Sul (ASPS) mais intenso que na regi{\~a}o da
Alta Subtropical do Atl{\^a}ntico Sul (ASAS) e seus deslocamentos
para leste. Na maioria dos eventos, a ASPS adentrou o sul da AS,
pr{\'o}ximo de 40°S, favorecendo anticiclog{\^e}nese, geralmente
sobre a parte norte/central da Argentina. O anticiclone formado
sobre o continente se intensificou e continuou a deslocar para
leste, favorecendo o avan{\c{c}}o do SF. Em m{\'e}dios e altos
n{\'{\i}}veis, ocorreu a amplifica{\c{c}}{\~a}o do cavado
frontal associado ao sistema em superf{\'{\i}}cie, o qual se
acentuou meridionalmente e se estendeu desde as latitudes
m{\'e}dias (55°S) at{\'e} os tr{\'o}picos, propiciando em
alguns eventos a forma{\c{c}}{\~a}o de um v{\'o}rtice
cicl{\^o}nico (subtropical). Em altos n{\'{\i}}veis, o Jato
Subtropical (JS) apresentou-se fraco e constatou-se nos eventos de
ver{\~a}o e primavera austral, a forma{\c{c}}{\~a}o do
V{\'o}rtice Cicl{\^o}nico em Altos N{\'{\i}}veis (VCAN), que
atuam nas proximidades do NEB, apenas nos dias finais do evento.
Com a forma{\c{c}}{\~a}o destes VCANs, os SFs permaneceram
semi-estacion{\'a}rios no NEB contribuindo para a
forma{\c{c}}{\~a}o da Zona de Converg{\^e}ncia do
Atl{\^a}ntico Sul (ZCAS). Al{\'e}m de ter sido observado
tamb{\'e}m, no dia da incurs{\~a}o destes eventos no sul do
Brasil, fraca intensidade dos SFs os quais posteriormente se
intensificaram nas proximidades dos estados de Minas Gerais/MG e
Rio de Janeiro/RJ, pela intera{\c{c}}{\~a}o com restos de outro
SF presente sobre a regi{\~a}o. Na atmosfera do CLA, notou-se que
a press{\~a}o atmosf{\'e}rica e a umidade relativa caem, com a
incurs{\~a}o do SF no NEB e depois aumentam, com deslocamento
dele na regi{\~a}o. A temperatura do ar apresenta um aumento com
a chegada, depois decresce com a perman{\^e}ncia e volta a
aumentar ap{\'o}s a passagem do SF. A velocidade do vento aumenta
com a incurs{\~a}o, e depois diminui com o deslocamento do SF. Na
maioria dos eventos ocorreram precipita{\c{c}}{\~o}es em
Alc{\^a}ntara. ABSTRACT: In this work, an observational synoptic
configuration pattern study was performed over the South America
(SA) and in the South Atlantic (SAO) and South Pacific Oceans
(SPO), in events of Frontal Systems (FSs) that reached the
Brazilian northeast coast and created an intense cloudiness in the
region of the Alc{\^a}ntara Launching Center (ALC). Seven cases
were selected, during all seasons of the year. They were analyzed
since its incursion on south of Brazil until its maximum incursion
in the country seeking to identify the possible synoptic
mechanisms that favored its motion. After that, the FS influence
was investigated, in the ALC atmosphere, through the
meteorological surface parameters analysis. It was noted an
incidence of cyclogenesis in the surface, commonly noticed in the
Rio Grande do Suls east coast. About the SAO and SPO, it was
noticed values of sea level pressure (SLP) in the region South
Pacific Subtropical High (SPSH) more intense than in the South
Atlantic Subtropical High (SASH) and its movements to east. In
most events, the SPSH enter the south of the SA, around 40°S,
favouring anticyclogenesis, usually located in the north/central
of Argentina. The anticyclone formed on the continent has expanded
and continued the movement to east, contributing to the
advancement of FS. In middle and high levels, happened the
amplification of the frontal rough associated to surface systems,
which it was intensified meridionaly and extended from middle
latitudes (55°S) until the tropics, and some of them providing the
formation of a cyclonic vortex (subtropical). In high levels, the
Subtropical Jet (SJ) presented week and was noticed in events of
summer and austral spring, the formation of Upper Troposphere
Cyclonic Vortex (UTCV), that act close to Northeast Brazil (NEB),
only in the later days of the event. With this VCANs formation,
the SFs stayed stationary in the NEB contributing to the formation
of South Atlantic Convergence Zone (SACZ). Besides it has been
also observed in the day of this incursions of this events in the
south of Brazil, weak intensity of SFs was lately intensified in
the boundaries of the States Minas Gerais/MG and Rio de
Janeiro/RJ, because of the interaction with lefts of another SF
present in the region. In the CLA atmosphere, we can notice that
the atmosphere pressure and relative humidity falls, with the
incursion of the NEBs FS and after they raises, with its movement
through the region. The air temperature presented a little
increase from the NEBs incursion, decrease with permanence and
increasing returns after FSs passage. The wind velocity increases
lightly with the incursion, and then decreases with the FS's
movement. In the most of events of precipitations happened in
Alc{\^a}ntara.",
committee = "Fisch, Gilberto Fernando (presidente) and Moscati, Marley
Cavalcante de Lima (orientadora) and Marques, Rosa de F{\'a}tima
Cruz (orientadora) and Gan, Manoel Alonso and Santos, Isimar de
Azevedo",
copyholder = "SID/SCD",
englishtitle = "Observacional study of the incursion on frontal systems on
northeast Brazil and its influence in the atmosphere of the
Alcantara Launching Center (CLA)",
language = "pt",
pages = "152",
ibi = "8JMKD3MGPBW/3366SSS",
url = "http://urlib.net/ibi/8JMKD3MGPBW/3366SSS",
urlaccessdate = "30 jun. 2024"
}