@PhDThesis{Santos:2021:PaAtVa,
author = "Santos, Luiz Fernando dos",
title = "Padr{\~o}es atmosf{\'e}ricos e variabilidade interanual do
in{\'{\i}}cio da esta{\c{c}}{\~a}o chuvosa nas regi{\~o}es
Centro-Oeste e Sudeste do Brasil",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2021",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2020-12-18",
keywords = "mon{\c{c}}{\~a}o da Am{\'e}rica do Sul,
precipita{\c{c}}{\~a}o, circula{\c{c}}{\~a}o atmosf{\'e}rica,
fluxo de calor, ondas tropicais, South American monsoon,
precipitation, atmospheric circulation, heat flux, tropical
waves.",
abstract = "O presente estudo investiga o comportamento do escoamento
atmosf{\'e}rico, de altos e baixos n{\'{\i}}veis, desde os
momentos que antecedem at{\'e} a data de in{\'{\i}}cio da
esta{\c{c}}{\~a}o chuvosa nas regi{\~o}es Centro-Oeste e
Sudeste do Brasil. Vale ressaltar que este tipo de an{\'a}lise
{\'e} poss{\'{\i}}vel devido ao fato de ambas as regi{\~o}es
estarem inseridas no Sistema de Mon{\c{c}}{\~a}o da Am{\'e}rica
do Sul, na qual apresenta uma esta{\c{c}}{\~a}o seca e uma
esta{\c{c}}{\~a}o {\'u}mida bem definidas. Al{\'e}m disso,
foram analisadas tamb{\'e}m as convers{\~o}es de energia
cin{\'e}tica entre os dist{\'u}rbios de v{\'a}rias escalas de
tempo e a atua{\c{c}}{\~a}o de oscila{\c{c}}{\~o}es
atmosf{\'e}ricas que interagem com a circula{\c{c}}{\~a}o na
Am{\'e}rica do Sul durante este per{\'{\i}}odo. A partir da
metodologia utilizada, as datas de in{\'{\i}}cio da
esta{\c{c}}{\~a}o chuvosa foram obtidas com base nos dados
di{\'a}rios de precipita{\c{c}}{\~a}o do Climate Prediction
Center em um per{\'{\i}}odo de 39 anos (1979-2017) para ambas as
regi{\~o}es. As datas foram separadas em tr{\^e}s categorias
(precoce, m{\'e}dia e tardia) e, com os dados da rean{\'a}lise
do Climate Forecast System Reanalysis e do Climate Forecast System
version 2 investigouse os padr{\~o}es din{\^a}micos e
f{\'{\i}}sicos da atmosfera e de superf{\'{\i}}cie durante o
in{\'{\i}}cio da esta{\c{c}}{\~a}o chuvosa nessas categorias.
A intera{\c{c}}{\~a}o entre as escalas sin{\'o}tica (2- 6
dias), submensal (7-29 dias) e intrassazonal (30-90 dias)
tamb{\'e}m foram investigadas, tal como os termos de
convers{\~a}o de energia cin{\'e}tica nessas escalas sobre a
Am{\'e}rica do Sul no trimestre de setembro a novembro. Dois
n{\'u}cleos de precipita{\c{c}}{\~a}o mais intensa foram
notados antes da data de in{\'{\i}}cio da esta{\c{c}}{\~a}o
chuvosa de ambas as regi{\~o}es de estudo. Tais n{\'u}cleos
ficam localizados a noroeste e sul do Brasil, os quais se conectam
durante o in{\'{\i}}cio da esta{\c{c}}{\~a}o chuvosa, elevando
abruptamente a precipita{\c{c}}{\~a}o no Sudeste e,
principalmente, no Centro-Oeste. Neste mesmo per{\'{\i}}odo,
observou-se tamb{\'e}m a conex{\~a}o entre a c{\'e}lula de
circula{\c{c}}{\~a}o meridional Hadley, de car{\'a}ter
regional, e a circula{\c{c}}{\~a}o de brisa de maior escala, que
atua zonalmente, nas duas regi{\~o}es estudadas. Normalmente, o
fluxo de calor sens{\'{\i}}vel se mostra superior ao fluxo de
calor latente antes da data de in{\'{\i}}cio da
esta{\c{c}}{\~a}o chuvosa na categoria precoce de ambas as
regi{\~o}es, j{\'a} na categoria tardia o fluxo de calor latente
mostrou-se mais intenso durante todo o per{\'{\i}}odo analisado.
As intera{\c{c}}{\~o}es de escalas mostram
combina{\c{c}}{\~o}es din{\^a}micas peculiares em cada
categoria que contribuem para o in{\'{\i}}cio da
esta{\c{c}}{\~a}o chuvosa. Notou-se ainda que h{\'a} um
relativo equil{\'{\i}}brio entre o termo de converg{\^e}ncia do
fluxo ageostr{\'o}fico com a convers{\~a}o barocl{\'{\i}}nica
no balan{\c{c}}o da energia cin{\'e}tica dos dist{\'u}rbios
sobre a Am{\'e}rica do Sul, tais termos s{\~a}o dominantes e
apresentaram padr{\~o}es relativamente opostos durante o
trimestre analisado. ABSTRACT: The present study investigates the
behavior of upper and lower levels of atmospheric flow that
leading up to the onset rainy season date in the Central- West and
Southeast of Brazil. That analysis is possible due to the fact
that both regions are part of the South American Monsoon System,
whose have a welldefined dry and wet seasons. The kinetic energy
conversions between eddies in different time scales and the
performance of atmospheric oscillations that interact with
circulation in South America during this period were also
analyzed. On the methodology used, the onset rainy season were
obtained based on the daily rainfall data from the Climate
Prediction Center during period of 39 years (1979-2017) for both
regions. The dates were separated into three categories (early,
mean, and late) and, using the Climate Forecast System Reanalysis
and the Climate Forecast System version 2, the dynamical and
physical patterns of the atmosphere and surface were investigated
during the season in these categories. The interaction between
synoptic (2-6 days), submonthly (7-29 days), and intraseasonal
(30-90 days) scales were also investigated, as well as the terms
of kinetic energy conversion in these time scales over South
America from September to November. Two strongest rainfall nuclei
were noted before the onset rainy season date in both study
regions. Such nuclei are located in the northwest and south of
Brazil, which connect during the onset rainy season, abruptly
increasing precipitation in the Southeast and, especially, in the
Central-Western. In this same time, there was also a connection
between the regional Hadley circulation cell and the larger-scale
breeze circulation over the two studied regions. Normally, the
sensible heat flux is superior to the latent heat flux before the
onset rainy season date in the early category of both regions,
whereas in the late category, the latent heat flux was more
intense throughout the analyzed period. The scale interactions
show peculiar dynamical combinations in each category and that
contributes to the onset rainy season. It was also noted that
there is a relative net balance between the convergence of the
ageostrophic flux term with the baroclinic conversion in the eddy
kinetic energy over South America, such the terms are dominant and
presented relatively opposite patterns during the quarter
analyzed.",
committee = "Ferreira, Nelson Jesuz (presidente) and Gan, Manoel Alonso
(orientador) and Coelho, Caio Augusto dos Santos and Silve, Adma
Raia and Calheiros, S{\^a}mia Regina Garcia",
englishtitle = "Atmospheric patterns and interannual variability of the onset
rainy season in the Central-West and Southeast of Brazil",
language = "pt",
pages = "178",
ibi = "8JMKD3MGP3W34R/43UNJH2",
url = "http://urlib.net/ibi/8JMKD3MGP3W34R/43UNJH2",
targetfile = "publicacao.pdf",
urlaccessdate = "27 abr. 2024"
}