@MastersThesis{Silva:2002:EsBaRa,
author = "Silva, Rita de C{\'a}ssia",
title = "Estudo do balan{\c{c}}o de radia{\c{c}}{\~a}o no Pantanal sul
mato-grossense",
school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
year = "2002",
address = "S{\~a}o Jos{\'e} dos Campos",
month = "2002-09-30",
keywords = "balan{\c{c}}o de radia{\c{c}}{\~a}o, radia{\c{c}}{\~a}o de
ondas curtas, radia{\c{c}}{\~a}o de ondas longas, albedo,
parametriza{\c{c}}{\~o}es, radiation balance, short wave
radiation, long wave radiation, albedo parametrizations.",
abstract = "Para o estudo da variabilidade das componentes do balan{\c{c}}o
de radia{\c{c}}{\~a}o na regi{\~a}o do Pantanal Sul
Mato-Grossense, medidas destas e de outras vari{\'a}veis
micrometeorol{\'o}gicas foram coletadas em experimento realizado
durante a esta{\c{c}}{\~a}o seca de 1999 (setembro) e entre o
per{\'{\i}}odo de transi{\c{c}}{\~a}o da esta{\c{c}}{\~a}o
seca para a chuvosa de 2000 (setembro a novembro). Assim, o estudo
incluiu avalia{\c{c}}{\~a}o das componentes do balan{\c{c}}o de
radia{\c{c}}{\~a}o, bem como a estimativa do saldo de
radia{\c{c}}{\~a}o atrav{\'e}s da radia{\c{c}}{\~a}o global
incidente (K\↓) e do balan{\c{c}}o de radia{\c{c}}{\~a}o
de ondas curtas (K*); a estimativa do fluxo de
radia{\c{c}}{\~a}o de ondas longas proveniente da atmosfera
(L\↓), utilizando m{\'e}todos anal{\'{\i}}ticos e
emp{\'{\i}}ricos propostos na literatura, ajustando seus
coeficientes para a regi{\~a}o estudada; a estimativa da
raz{\~a}o entre a radia{\c{c}}{\~a}o fotossinteticamente ativa
incidente (PAR\↓) e K\↓, considerando outras
vari{\'a}veis meteorol{\'o}gicas; a an{\'a}lise do saldo de
radia{\c{c}}{\~a}o na faixa do infravermelho pr{\'o}ximo; a
avalia{\c{c}}{\~a}o da variabilidade do albedo nos intervalos
das radia{\c{c}}{\~o}es de ondas curtas, fotossinteticamente
ativa e infravermelha pr{\'o}xima; e a estimativa do albedo em
fun{\c{c}}{\~a}o do {\^a}ngulo solar zenital. Os resultados
mostraram que houve algumas varia{\c{c}}{\~o}es significativas
em determinadas componentes do balan{\c{c}}o de
radia{\c{c}}{\~a}o entre um ano e outro, especialmente em
raz{\~a}o das diferen{\c{c}}as nas condi{\c{c}}{\~o}es da
superf{\'{\i}}cie (vegeta{\c{c}}{\~a}o mais seca em 1999 e
mais verde no ano seguinte). Avaliou-se o desempenho de sete
diferentes formula{\c{c}}{\~o}es para a estimativa de L\↓
considerando separadamente os dias de c{\'e}u claro de 1999 (8) e
os de 2000 (16). Usando coeficientes locais, de modo geral os
melhores ajustes para ambos os anos foram obtidos com a
formula{\c{c}}{\~a}o de Prata (fun{\c{c}}{\~a}o da
press{\~a}o de vapor e da temperatura). Outrossim, a
discrimina{\c{c}}{\~a}o entre as formula{\c{c}}{\~o}es feitas
a partir do algoritmo de Box e Hill, indicou que a melhor
parametriza{\c{c}}{\~a}o ajustada para 1999 foi a de Prata,
seguindo-se as de Brunt, de Idso, de Satterlund, de Idso e
Jackson, de Brutasert e de Swinbank. Para os dados de 2000 a
melhor parametriza{\c{c}}{\~a}o foi a de Idso, seguindo-se das
de Swinbank, de Brunt, de Idso e Jackson, de Prata, de Brutsaert e
de Satterlund. O valor m{\'e}dio da raz{\~a}o [eta]
(PAR\↓/K\↓) para o per{\'{\i}}odo de 1999 foi
igual a 0,48±0,02, enquanto para o per{\'{\i}}odo de 2000 foi
0,46±0,01. O albedo m{\'e}dio das radia{\c{c}}{\~o}es solar
([alpha]K), PAR ([alpha]PAR) e IVP ([alpha]IVP) em todos os dias
avaliados foram 0,17±0,024; 0,08±0,007; 0,26±0,025 em 1999,
respectivamente. Em 2000, os respectivos valores foram 0,17±0,022;
0,06±0,003; 0,26±0,060. Apresentam-se tr{\^e}s modelos para a
estimativa de PAR a partir de diferentes par{\^a}metros
meteorol{\'o}gicos. Al{\'e}m disso, apresentam-se
equa{\c{c}}{\~o}es para a estimativa do albedo em
fun{\c{c}}{\~a}o do {\^a}ngulo de eleva{\c{c}}{\~a}o do Sol,
ajustadas por polin{\^o}mios de segundo grau, as quais devem ser
usadas com cautela, uma vez que os coeficientes de
correla{\c{c}}{\~a}o foram relativamente baixos, principalmente
em 1999. Finalmente, ressalta-se que as diferen{\c{c}}as
observadas nos par{\^a}metros microclim{\'a}ticos e radiativos
entre um per{\'{\i}}odo e outro, podem ser resultantes das
diferen{\c{c}}as clim{\'a}ticas entre os dois anos. ABSTRACT: To
study the variability of the components of the radiative balance
in the Southern Mato Grosso Pantanal, measurements of these
components and of the micrometeorological variables were obtained
in experiments during both the dry season of 1999 (September), and
the transition from the dry to the rainy season of 2000 (September
to November). Thus, the components of the radiation balance were
evaluated, as well as the estimative of the net radiation through
the global incident radiation (K\↓) and the short wave
radiation balance (K*). Also, the estimative of the long wave flux
from the atmosphere (L\↓) was obtained, using analytical
and empirical methods proposed in the literature, with the
adjustment of their coefficients to the region. The estimative of
the ratio between the photosynthetically active radiation
(PAR\↓) and K\↓, taking into account other
meteorological variables, was made. The analysis of the net
radiation in the near infra-red region, plus the evaluation of the
variability of the albedo in the short wave, PAR and near
infra-red regions, and the estimative of the albedo as a function
of the zenital angle were effected. The results show that, from
one year to the other, there were significant variations in
certain components of the radiation balance. They were due
especially to the differences in the surface conditions, that is,
drier vegetation in 1999, opposed to a greener subsequent year.
The performance of seven different models for the estimation of
L\↓ was evaluated, considering separately the data measured
in 1999 (8 clear days) and in 2000 (16 clear days). Using local
coefficients, the best adjustment, in general, was obtained with
Prata's model, which is a function of vapor pressure and
temperature. Further, the discrimination among these models using
the algorithm of Box and Hill, also indicated Prata's
parametrization as the best for 1999, followed by the ones of
Brunt, of Idso, of Satterlund, of Idso and Jackson, and of
Swinbank. For the data of 2000, the best parametrization was
Idso's, followed by the ones of Swinbank, of Brunt, of Idso and
Jackson, of Prata, of Brutsaert, and of Satterlund. The average
value of the ratio [eta] (PAR\↓/K\↓) for the 1999
period was 0.48±0.02, while for the 2000 period it was 0.46±0.01.
The average albedoes of the solar ([alpha]K), of the PAR
([alpha]PAR) and of the NIR ([alpha]IVP) radiations, for the days
considered in 1999 were, respectively, 0.17±0.024, 0.08±0.007 and
0.26±0.025; for 2002, they were, respectively, 0.17±0.022,
0.06±0.003 and 0.26±0.060. Three models are presented for the PAR,
using meteorological parameters. Also, quadratic equations are
presented for the estimation of the albedo as a function of the
solar elevation angle; however, as their correlation coefficients
were relatively low, they should be used with care. Finally, it
should be noted that the differences observed for the
microclimatic and radiation parameters in 1999 and in 2000 may be
due to the different climatic conditions in both years.",
committee = "Fisch, Gilberto Fernando (presidente) and Alval{\'a}, Regina
C{\'e}lia dos Santos (orientadora) and Abreu S{\'a}, Leonardo
Deane de and Manzi, Antonio Ocimar and Andr{\'e},
Rom{\'{\i}}sio Geraldo Bouhid",
copyholder = "SID/SCD",
englishtitle = "Study of radiation balance in the Pantanal sul mato-grossense",
language = "pt",
pages = "213",
ibi = "6qtX3pFwXQZ3P8SECKy/yBqqN",
url = "http://urlib.net/ibi/6qtX3pFwXQZ3P8SECKy/yBqqN",
targetfile = "publicacao.pdf",
urlaccessdate = "08 maio 2024"
}