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@MastersThesis{Madruga:1997:DiReDe,
               author = "Madruga, Jaqueline Leal",
                title = "Diferen{\c{c}}as relativas no desempenho de algor{\'{\i}}tmos 
                         de corre{\c{c}}{\~a}o atmosf{\'e}rica e bio-{\'o}pticos para o 
                         processamento de imagens CZCS no Oceano Atl{\^a}ntico Sudoeste",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "1997",
              address = "Sao Jose dos Campos",
                month = "1997-02-26",
             keywords = "oceanografia, Oceano Atl{\^a}ntico, calibra{\c{c}}{\~a}o, 
                         algoritmos, correla{\c{c}}{\~a}o, fitoplancton, 
                         corre{\c{c}}{\~a}o atmosf{\'e}rica, sat{\'e}lite NIMBUS, 
                         imageador da cor de zona costeira, calibration, oceanography, 
                         algorithms, CZCS.",
             abstract = "Existem na literatura v{\'a}rios algor{\'{\i}}tmos para 
                         obten{\c{c}}{\~a}o de estimativas de concentra{\c{c}}{\~a}o de 
                         pigmentos no oceano a partir de imagens orbitais. Estes 
                         algor{\'{\i}}tmos visam a remo{\c{c}}{\~a}o de efeitos 
                         atmosf{\'e}ricos e ao c{\'a}lculo da concentra{\c{c}}{\~a}o de 
                         pigmento. Neste trabalho s{\~a}o descritos e comparados dois 
                         algor{\'{\i}}tmos de corre{\c{c}}{\~a}o atmosf{\'e}rica para 
                         dez imagens CZCS; o algor{\'{\i}}tmo interativo do Smith e 
                         Wilson (1981) (S), o qual utiliza o modelo de espalhamento simples 
                         e o de Gordon et al. (1988) (G) que utiliza o modelo de 
                         espalhamento m{\'u}ltiplo. Para a estimativa da 
                         concentra{\c{c}}{\~a}o de pigmento foram usados o 
                         algor{\'{\i}}tmo padr{\~a}o de dois canais de Gordon et al. 
                         (1983) (P1) e um de tr{\^e}s canais de Dennis Clark 
                         (Muller-Karger et al., 1990) (P2). Devido a aus{\^e}ncia de dados 
                         in situ simult{\^a}neos a passagem do sat{\'e}lite, o objetivo 
                         do trabalho restringiu-se {\`a} compara{\c{c}}{\~a}o entre os 
                         resultados quando combinados os diferentes algor{\'{\i}}tmos. 
                         Al{\'e}m disso foram realizadas compara{\c{c}}{\~o}es entre 
                         dados orbitais e dados hist{\'o}ricos in situ. Concluiu-se que 
                         para {\'a}guas profundas n{\~a}o ocorrem varia{\c{c}}{\~o}es 
                         consider{\'a}veis ao se alterar as combina{\c{c}}{\~o}es de 
                         algor{\'{\i}}tmos. J{\'a} para {\'a}guas de plataforma 
                         continental as discrep{\^a}ncias entre os resultados s{\~a}o 
                         bastante acentuadas, principalmente para concentra{\c{c}}{\~o}es 
                         superiores a 1,0 mg/m3 , onde os valores podem ser 
                         question{\'a}veis em fun{\c{c}}{\~a}o da grande quantidade de 
                         material em suspens{\~a}o. Os resultados sugerem que, para as 
                         imagens completas, os distintos algor{\'{\i}}tmos 
                         bio-{\'o}pticos apresentam maior impacto na 
                         determina{\c{c}}{\~a}o das concentra{\c{c}}{\~o}es de pigmento 
                         do que os algor{\'{\i}}tmos de corre{\c{c}}{\~a}o 
                         atmosf{\'e}rica, visto que o algor{\'{\i}}tmo de Dennis Clark 
                         superestima os valores apresentados pelo algor{\'{\i}}tmo de 
                         Gordon et al. (1983), independente da corre{\c{c}}{\~a}o 
                         atmosf{\'e}rica utilizada. As estimativas de 
                         distribui{\c{c}}{\~a}o espacial de pigmentos no Oceano 
                         Atl{\^a}ntico Sudoeste adjacente {\`a} costa brasileira, 
                         apresentadas pela primeira vez no presente trabalho, dever{\~a}o 
                         ser aperfei{\c{c}}oadas atrav{\'e}s de projeto de 
                         calibra{\c{c}}{\~a}o de novos dados orbitais com dados coletados 
                         in situ. ABSTRACT: Orbital images have been used to estimate ocean 
                         pigment concentration through image analysis using different 
                         computational algorithms. These algorithms remove anomalous 
                         effects from atmosphere and calculate the ocean pigment 
                         concentration. Two algorithms were used to correct atmospheric 
                         effects for ten images: the interactive algorithm based on a 
                         simple scattering model of Smith and Wilson (1981) (S) and an 
                         algorithm created by Gordon et al. (1988) (G), which considers the 
                         multiple scattering model. The pigment estimates were made 
                         considering two bio-optical algorithms: the standard two channel 
                         algorithm from Gordon et al. (1983) (P1) and the three channel 
                         algorithm elaborated by Dennis Clark (P2) (M{\"u}ller-Karger et 
                         al.,1990). The objective of the present study was to compare the 
                         results obtained from four algorithm's combinations (8P1, 8-P2, 
                         G-P1, G-P2), since there was not in situ data available at the 
                         same time of the satellite imagery. Orbital and historical in situ 
                         data were also compared. It was possible to observe that for deep 
                         ocean waters there was little variation among the algorithm' s 
                         combinations. However, for continental shelf waters this 
                         variations were more pronounced, mainly for concentrations above 
                         1,0 mg/m3, such values can be questioned due to the great amount 
                         of suspended material. For the whole set of images, the results 
                         suggest that the bio-optical algorithms have a strong impact on 
                         the pigment concentration determination, since the Dennis Clark 
                         algorithm has always produced higher concentration values than the 
                         one from Gordon et al. (1983), independently of the applied 
                         atmospheric correction algorithms. The estimations of spatial 
                         pigment distribution in Southwestern Atlantic Ocean adjacent to 
                         the Brazilian coast showed for the first time in this paper, 
                         should be improved by calibration of new orbital data set as well 
                         as in situ data.",
            committee = "Vianna, Marcio Luiz (presidente/orientador) and Garcia, Carlos 
                         Alberto Eiras (orientador) and Lorenzetti, Jo{\~a}o Ant{\^o}nio 
                         and Novo, Evlyn Marcia Le{\~a}o de Moraes and Galv{\~a}o, 
                         S{\^o}nia Maria Flores Gianesella",
           copyholder = "SID/SCD",
         englishtitle = "Relative differences in the atmosfepheric correction and 
                         bio-optical algorithm performace for CZCS image processing in the 
                         Southwestern Atlantic Ocean",
                label = "7720",
             language = "pt",
                pages = "166",
                  ibi = "6qtX3pFwXQZ3r59YD6/GPf8r",
                  url = "http://urlib.net/rep/6qtX3pFwXQZ3r59YD6/GPf8r",
           targetfile = "publicacao.pdf",
        urlaccessdate = "17 jan. 2021"
}


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