@PhDThesis{Chaves:2003:CoATe,
author = "Chaves, Rosane Rodrigues",
title = "Conex{\~o}es entre a temperatura da superf{\'{\i}}cie do Oceano
Atl{\^a}ntico e a convec{\c{c}}{\~a}o de ver{\~a}o sobre a
Am{\'e}rica do Sul e {\'a}reas adjacentes",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2003",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2003-08-15",
keywords = "Oceano Atl{\^a}ntico, Am{\'e}rica do Sul, zona de
converg{\^e}ncia do Atl{\^a}ntico Sul (ZCAS), temperatura da
superf{\'{\i}}cie do mar (TSM), intera{\c{c}}{\~a}o
oceano-atmosfera, Atlantic Ocean, South America, South Atlantic
convergence zone, sea surface temperature (SST), air water
interactions.",
abstract = "A intera{\c{c}}{\~a}o entre a Temperatura da Superf{\'{\i}}cie
do Mar (TSM) do Oceano Atl{\^a}ntico e a convec{\c{c}}{\~a}o de
ver{\~a}o sobre a Am{\'e}rica do Sul {\'e} estudada
atrav{\'e}s de m{\'e}todos estat{\'{\i}}sticos de an{\'a}lise
multivariada e de simula{\c{c}}{\~o}es num{\'e}ricas. A
an{\'a}lise observacional {\'e} realizada atrav{\'e}s da
An{\'a}lise de Componentes Principais, Decomposi{\c{c}}{\~a}o
em Valores Singulares e de an{\'a}lise de compostos dos dados de
TSM do COADS, ROL do CDC/NOAA e vento da rean{\'a}lise do
NCEP/NCAR para o per{\'{\i}}odo de 1979 a 2001. Nesta
an{\'a}lise os resultados mostram que a convec{\c{c}}{\~a}o
sobre a por{\c{c}}{\~a}o oce{\^a}nica da Zona de
Converg{\^e}ncia do Atl{\^a}ntico Sul (ZCAS) est{\'a} associada
{\`a}s anomalias positivas de TSM sobre o Atl{\^a}ntico Sul
(40šS-Equador). No entanto, na an{\'a}lise observacional, a
associa{\c{c}}{\~a}o da por{\c{c}}{\~a}o continental da ZCAS
{\`a} TSM n{\~a}o {\'e} evidente. Os mecanismos
f{\'{\i}}sicos respons{\'a}veis pelo estabelecimento das
conex{\~o}es entre a TSM do Atl{\^a}ntico Sul e a
convec{\c{c}}{\~a}o sobre a Am{\'e}rica do Sul e {\'a}reas
adjacentes s{\~a}o estudados atrav{\'e}s de
simula{\c{c}}{\~o}es num{\'e}ricas com o Modelo de
Circula{\c{c}}{\~a}o Geral da Atmosfera (MCGA) CPTEC/COLA e o
Modelo de Circula{\c{c}}{\~a}o Geral do Oceano (MCGO) MOM. Os
resultados das simula{\c{c}}{\~o}es mostram que a variabilidade
da ZCAS est{\'a} associada {\`a}s anomalias de TSM do
Atl{\^a}ntico Sul e que existe um forte acoplamento entre a
atmosfera e o oceano adjacente a este sistema meteorol{\'o}gico.
As anomalias positivas de TSM sobre o Atl{\^a}ntico Sul tendem a
intensificar e posicionar a ZCAS em latitudes ao norte da sua
posi{\c{c}}{\~a}o climatol{\'o}gica, enquanto que o
resfriamento desta Bacia tende a desintensificar a ZCAS. A TSM do
Oceano Atl{\^a}ntico Sul for{\c{c}}a a convec{\c{c}}{\~a}o
sobre a costa do sul do NEB, norte do Sudeste e {\'a}reas
oce{\^a}nicas adjacentes dinamicamente, atrav{\'e}s da
altera{\c{c}}{\~a}o dos padr{\~o}es de fluxo de umidade entre o
oceano e a atmosfera, e termodinamicamente, atrav{\'e}s da
altera{\c{c}}{\~a}o dos mecanismos de instabiliza{\c{c}}{\~a}o
da atmosfera. Os experimentos num{\'e}ricos com o MCGO mostram
que a ZCAS causa o aparecimento de anomalias negativas de TSM ou a
desintensifica{\c{c}}{\~a}o das anomalias positivas de TSM no
Atl{\^a}ntico Sul sob este sistema. Os resultados das
simula{\c{c}}{\~o}es num{\'e}ricas com o MCGO indicam que as
anomalias negativas de TSM sob a regi{\~a}o da ZCAS s{\~a}o
resultados de processos radiativos. Nesta intera{\c{c}}{\~a}o, o
{"}feedback{"} negativo (feedback nuvem/onda curta e a TSM)
predomina com uma ordem de magnitude maior em rela{\c{c}}{\~a}o
ao {"}feedback{"} negativo din{\^a}mico (mecanismo de bombeamento
de Ekman). Este {\'u}ltimo mecanismo se manifesta apenas quando
ocorre forte evento de ZCAS. Aparentemente, o maior contraste
entre a temperatura do Atl{\^a}ntico Sul e do continente,
associado com a intensifica{\c{c}}{\~a}o da
circula{\c{c}}{\~a}o de mon{\c{c}}{\~a}o, n{\~a}o contribui
com a intensifica{\c{c}}{\~a}o da ZCAS. Os resultados da
an{\'a}lise observacional e dos experimentos num{\'e}ricos
mostram que as anomalias de TSM do Oceano Atl{\^a}ntico Norte
(Equador-40šN) durante o per{\'{\i}}odo de ver{\~a}o austral
est{\~a}o associadas apenas com a convec{\c{c}}{\~a}o no norte
da Am{\'e}rica do Sul. ABSTRACT: The interaction between the sea
surface temperature (SST) over the Atlantic Ocean and the summer
convection over South America and adjacent areas is studied with
the help of statistical analysis and numerical experiments. The
observational analysis is done through Principal Components
Analysis, Singular Values Decomposition and composites analysis
with SST from COADS, Outgoing Longwave Radiation from CDC/NOAA
(1979-2001) and wind field from NCEP/NCAR Reanalysis. The results
show that the South Atlantic Convergence Zone (SACZ) convection
over the ocean is associated with the warm waters in this Basin
(40šS-Equador). The physical mechanisms responsible for the
establishment of these connections between the SST in the South
Atlantic Ocean and the summer convection over South America are
studied through separate runs of the numerical experiments with
the atmospheric general circulation model (AGCM) CPTEC/COLA and
ocean general circulation model (OGCM) Geophysical Fluid Dynamics
Laboratory (GFDL) Modular Ocean Model (MOM). The results of the
AGCM and OGCM experiments show that the SACZ is associated with
SST anomalies in the South Atlantic and there is a strong coupling
between the atmosphere and the ocean adjacent to this
meteorological system. The warming of South Atlantic Ocean tends
to intensify and move the SACZ northward of its climatological
position; meanwhile the cooling of South Atlantic tends to weaken
the SACZ. The SST on the South Atlantic Ocean force the SACZ
convection dynamically, through change in the humidity flux
patterns over South America and termodynamically, through change
in the destabilization mechanisms of the atmosphere. The OGCM
experiments show that the SACZ cause cold SST anomalies or the
desintensification of the warm SST anomalies in the South Atlantic
Ocean under this meteorological system, result of radiative
processes. In this interaction, the negative feedback
(Cloud/Short-Wave - SST feedback) predominates and it is one order
of magnitude larger than the negative dynamic feedback (Ekman
pumping). The latter is verified only during strong SACZ events.
The results show that the contrast between the surface temperature
over South Atlantic and South America, associated with
intensification of monsson circulation, does not contribute to the
intensification of the SACZ. The results from observational
analysis and numerical experiments show that the positive SST
anomalies in the North Atlantic Ocean (Equador - 40šN) are
associated only with the summer convecction over the northernmost
region of South America.",
committee = "Satyamurty, Prakki (presidente) and Nobre, Paulo (orientador) and
Bonatti, Jos{\'e} Paulo and Campos, Edmo Jos{\'e} Dias and
Ambrizzi, T{\'e}rcio",
copyholder = "SID/SCD",
englishtitle = "Connections between the sea surface temperature over the Atlantic
Ocean and the summer convection over South America and adjacent
areas",
language = "pt",
pages = "204",
ibi = "6qtX3pFwXQZ3P8SECKy/zQ9g6",
url = "http://urlib.net/ibi/6qtX3pFwXQZ3P8SECKy/zQ9g6",
targetfile = "publicacao.pdf",
urlaccessdate = "30 jun. 2024"
}