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@PhDThesis{Curtarelli:2016:VaEsTe,
               author = "Curtarelli, Marcelo Pedroso",
                title = "Variabilidade espacial e temporal do fluxo difusivo de CO2 no 
                         reservat{\'o}rio hidrel{\'e}trico de Tucuru{\'{\i}}, 
                         Amaz{\^o}nia, Brasil",
               school = "Instituto Nacional de Pesquisas Espaciais (INPE)",
                 year = "2016",
              address = "S{\~a}o Jos{\'e} dos Campos",
                month = "2016-03-10",
             keywords = "emiss{\~a}o de di{\'o}xido carbono, reservat{\'o}rios 
                         hidrel{\'e}tricos, Amaz{\^o}nia, aplica{\c{c}}{\~o}es 
                         multissensores, modelos tridimensionais, carbon dioxide emission, 
                         hydroelectric reservoirs, Amazon region, multisensor applications, 
                         three-dimensional models.",
             abstract = "A hip{\'o}tese que motivou esta pesquisa foi a de que a atual 
                         estimativa de emiss{\~a}o total de carbono por reservat{\'o}rios 
                         hidrel{\'e}tricos Amaz{\^o}nicos {\'e} imprecisa, uma vez que a 
                         variabilidade espacial e temporal do fluxo difusivo de 
                         CO\$_{2}\$ n{\~a}o {\'e} considerada de maneira adequada. 
                         Desta forma, o presente trabalho teve o objetivo de estudar a 
                         din{\^a}mica da variabilidade espacial e temporal do fluxo 
                         difusivo de CO\$_{2}\$ no reservat{\'o}rio de Tucuru{\'{\i}}, 
                         Par{\'a}, ao longo das esta{\c{c}}{\~o}es de ver{\~a}o e 
                         inverno, e em condi{\c{c}}{\~o}es de clima atual e futuro. Para 
                         tanto foi utilizada uma abordagem inovadora que buscou integrar 
                         dados coletados \emph{in situ}, dados obtidos por sensoriamento 
                         remoto e o uso de modelagem num{\'e}rica tridimensional para 
                         simula{\c{c}}{\~a}o do fluxo difusivo de CO\$_{2}\$ . Foram 
                         realizados experimentos em condi{\c{c}}{\~o}es de clima presente 
                         (ano 2013) e clima futuro (ano 2100), considerando dois 
                         cen{\'a}rios distintos do ponto de vista clim{\'a}tico e de 
                         mudan{\c{c}}as no uso e cobertura do solo na bacia de 
                         contribui{\c{c}}{\~a}o do reservat{\'o}rio. Os resultados 
                         obtidos a partir dos experimentos realizados em 
                         condi{\c{c}}{\~o}es de clima presente mostraram que o fluxo 
                         difusivo de CO\$_{2}\$ apresenta alta variabilidade espacial e 
                         temporal em Tucuru{\'{\i}}. Temporalmente, o fluxo difusivo de 
                         CO\$_{2}\$ variou, em m{\'e}dia, entre -86 e -24 mg C 
                         m\$^{-2}\$ hora\$^{-1}\$ ao longo do dia no ver{\~a}o e entre 
                         -105 e -30 mg C m\$^{-2}\$ hora-1 ao longo do dia no inverno. Em 
                         ambos os per{\'{\i}}odos analisados as maiores taxas de 
                         emiss{\~a}o foram observadas no per{\'{\i}}odo noturno e 
                         in{\'{\i}}cio da manh{\~a} e as menores no per{\'{\i}}odo da 
                         tarde. O valor di{\'a}rio m{\'e}dio do fluxo difusivo de 
                         CO\$_{2}\$ obtido para o per{\'{\i}}odo de ver{\~a}o foi de 
                         -1.338 \$\pm\$ 1.335 mg C m\$^{-2}\$ dia\$^{-1}\$ e de 
                         -1.395 \$\pm\$ 925 mg C m\$^{-2}\$ dia\$^{-1}\$ para o 
                         per{\'{\i}}odo de inverno. Do ponto de vista espacial, o fluxo 
                         difusivo de CO\$_{2}\$ apresentou um padr{\~a}o 
                         heterog{\^e}neo durante todo o ver{\~a}o, variando, em 
                         m{\'e}dia, entre -6.950 (zona de transi{\c{c}}{\~a}o) e 32 mg C 
                         m\$^{-2}\$ dia\$^{-1}\$ (absor{\c{c}}{\~a}o no interior dos 
                         igarap{\'e}s). Por outro lado, durante o inverno o fluxo difusivo 
                         de CO\$_{2}\$ apresentou um padr{\~a}o homog{\^e}neo, com 
                         grande parte da superf{\'{\i}}cie do reservat{\'o}rio 
                         apresentando valores pr{\'o}ximos {\`a} m{\'e}dia espacial. Os 
                         principais fatores ambientais influenciando a evas{\~a}o de 
                         CO\$_{2}\$ em Tucuru{\'{\i}} foram a velocidade de troca 
                         gasosa, temperatura da coluna d'{\'a}gua, press{\~a}o parcial de 
                         CO\$_{2}\$ na {\'a}gua e componentes do balan{\c{c}}o 
                         energ{\'e}tico na camada de mistura. Desta forma a 
                         atua{\c{c}}{\~a}o de sistemas convectivos de mesoescala sobre o 
                         reservat{\'o}rio de Tucuru{\'{\i}} apresentou o potencial de 
                         aumentar a evas{\~a}o de CO\$_{2}\$ em cerca de 28\% nos dias 
                         em que ocorrem, uma vez que estes sistemas alteram as 
                         condi{\c{c}}{\~o}es ambientais na regi{\~a}o. Em 
                         condi{\c{c}}{\~o}es de clima futuro, os experimentos realizados 
                         apontam que o fluxo difusivo poder{\'a} ser impactado de 
                         diferentes formas, sendo a eutrofiza{\c{c}}{\~a}o do 
                         reservat{\'o}rio, associada {\`a}s mudan{\c{c}}as no uso e 
                         cobertura do solo na bacia de contribui{\c{c}}{\~a}o, um dos 
                         principais fatores que ir{\'a} influenciar as emiss{\~o}es de 
                         CO\$_{2}\$ no futuro. Os resultados alcan{\c{c}}ados na 
                         pesquisa permitiram aceitar a hip{\'o}tese inicial, sendo 
                         demonstrado que a varia{\c{c}}{\~a}o espacial e temporal do 
                         fluxo difusivo de CO\$_{2}\$ s{\~a}o aspectos importantes a 
                         serem considerados durante as estimativas de emiss{\~a}o de C em 
                         reservat{\'o}rio hidrel{\'e}tricos Amaz{\^o}nicos. Extrapolando 
                         os resultados obtidos nesta pesquisa para todo o bioma 
                         Amaz{\^o}nico, especula-se que a emiss{\~a}o total de carbono 
                         por reservat{\'o}rios de usinas hidrel{\'e}tricas possa ser 
                         at{\'e} 22\% menor do que a estimativa mais atual reportada na 
                         literatura (9 Tg C ano\$^{-1}\$). Esta diferen{\c{c}}a 
                         significativa n{\~a}o deve ser negligenciada, uma vez que a 
                         emiss{\~a}o de carbono {\'e} um fator chave quando se comparam 
                         os impactos ambientais de diferentes fontes de gera{\c{c}}{\~a}o 
                         de energia el{\'e}trica podendo influenciar a tomada de 
                         decis{\~a}o para a escolha da fonte mais adequada do ponto de 
                         vista ambiental e no local de constru{\c{c}}{\~a}o de novos 
                         empreendimentos hidrel{\'e}tricos. ABSTRACT: The hypothesis that 
                         motivated this research was that the current estimate of the total 
                         carbon emissions by Amazonian hydroelectric reservoirs is 
                         inaccurate, since the spatial and temporal variability of the 
                         diffusive CO\$_{2}\$ flux is not considered properly. Thus, this 
                         study aimed to study the spatial and temporal variability of the 
                         diffusive CO\$_{2}\$ flux in the Tucuru{\'{\i}} reservoir, 
                         Par{\'a}, along the summer and winter seasons, and for current 
                         and future climate conditions. For this purpose we used an 
                         innovative approach which integrates data collected \emph{in 
                         situ}, data obtained by remote sensing and the use of 
                         three-dimensional numerical modeling to simulate the CO\$_{2}\$ 
                         diffusive flux. Experiments were carried out for present climate 
                         conditions (year 2013) and future climate conditions (2100), 
                         considering two different scenarios of climate and land use and 
                         land cover changes in the reservoir basin. The results obtained 
                         for the experiments conducted under present climate conditions 
                         showed that the diffusive CO\$_{2}\$ flux has a high spatial and 
                         temporal variability in Tucuru{\'{\i}}. Temporally, the 
                         diffusive flux of CO\$_{2}\$ ranged, on average, between -86 and 
                         -24 mg C m\$^{-2}\$ hour\$^{-1}\$ throughout the day in the 
                         summer season and between -105 and -30 mg C m\$^{-2}\$ 
                         hour\$^{-1}\$ during the winter season. In seasons analyzed the 
                         highest emission rate was observed during the night and early 
                         morning, and the lowest rate during the afternoon. The mean daily 
                         value of the CO\$_{2}\$ diffusive flux obtained for the summer 
                         period was -1338 \$\pm\$ 1.335 mg C m\$^{-2}\$ day\$^{-1}\$ 
                         and -1395 \$\pm\$ 925 mg C m\$^{-2}\$ day\$^{-1}\$ for the 
                         winter period. From the spatial point of view, the diffusive flux 
                         of CO\$_{2}\$ showed a heterogeneous pattern during the summer, 
                         ranging between -6.950 (transition zone) and 32 mg C m\$^{-2}\$ 
                         day\$^{-1}\$ (absorption within the littoral zone). Moreover, 
                         during the winter season the diffusive flux of CO\$_{2}\$ showed 
                         a homogeneous pattern. The main environmental factors influencing 
                         the evasion of CO\$_{2}\$ in Tucuru{\'{\i}} reservoir were the 
                         gas exchange piston velocity, temperature of the water column, 
                         partial pressure of CO\$_{2}\$ in the water and the components 
                         of energy balance in the mixed layer. Thus the occurrence of 
                         mesoscale convective systems over Tucuru{\'{\i}} reservoir had 
                         the potential to increase the evasion of CO\$_{2}\$ by about 
                         28\% on days in which they occurs, since these systems change the 
                         environmental conditions in the reservoir region. For the 
                         experiments under future climate conditions, the results showed 
                         that the diffusive CO\$_{2}\$ flux may be affected in different 
                         ways and the eutrophication of the reservoir, associated with the 
                         changes in land use and land cover in the reservoir basin, is one 
                         of the main factors that will influence the emissions of 
                         CO\$_{2}\$ in the future. The outcomes of this research allowed 
                         to accept the initial hypothesis, and demonstrated that the 
                         spatial and temporal variability of CO\$_{2}\$ diffusive flux 
                         are important aspects to be considered for the total carbon 
                         emission estimates in hydroelectric reservoir located at Amazon 
                         biome. Extrapolating the results obtained in this study for the 
                         entire Amazon biome, it is speculated that the total carbon 
                         emissions by hydroelectric reservoirs can be up to 22\% less than 
                         the latest estimate reported in the literature (9 Tg C 
                         yr\$^{-1}\$). This significant difference should not be 
                         neglected, since the carbon footprint is a key factor when 
                         comparing the environmental impacts of different sources of 
                         electricity generation and can influence the decision-making 
                         process for choosing the most appropriate source and the 
                         construction site of new hydroelectric projects.",
            committee = "Stech, Jos{\'e} Luiz (presidente) and Lorenzzetti, Jo{\~a}o 
                         Antonio (orientador) and Kampel, Milton and Fernandez, Julio Pablo 
                         Reyes and Damazio, Jorge Machado and Tundisi, Jos{\'e} Galizia",
           copyholder = "SID/SCD",
         englishtitle = "Spatio-temporal variability of diffusive CO2 flux in the 
                         Tucuru{\'{\i}} hydroelectric reservoir, Amaz{\^o}nia, Brazil",
             language = "pt",
                pages = "183",
                  ibi = "8JMKD3MGP3W34P/3L6FL6E",
                  url = "http://urlib.net/rep/8JMKD3MGP3W34P/3L6FL6E",
           targetfile = "publicacao.pdf",
        urlaccessdate = "05 dez. 2020"
}


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