Water resources availability could be affected by alterations of hydrologic processes as a result of climate change. Global projections of climate change indicate negative impacts on water systems with increasing flooding and drought events. This investigation presents the modeling of climate change effects on the hydrology and water resources availability in the Rio Conchos basin, the main tributary of the lower portion of the bi-national Rio Grande/Bravo basin, and its impact on the water treaty signed between the United States of America and Mexico in 1944. One of the problems most relevant to the study basin is the frequent occurrence of long drought periods. Coupled with increased water demands and low irrigation efficiencies, the competition for water resources is high on both sides of the border. Three main parts are addressed in this research. First, a hydrologic model has been developed using the one-dimensional, 2 layer soil moisture accounting scheme embedded in a water evaluation and planning model. Second, downscaled precipitation and temperature data, from five general circulation models for two emission scenarios, A1B and A2, were used as inputs to the Rio Conchos hydrologic model to determine the effect on basin hydrology. A multi-model ensemble is developed and several techniques, such as probability density functions, wavelet analysis, and trend analysis, are used to assess the impacts. Third, a water resources planning model for the basin has been developed, which integrates the hydrologic model and water management modeling, to evaluate the impacts on the entire water system and simulate adaptive strategies to mitigate climate change in the study basin. Skill-weighted multi-model ensemble results show that annual average runoff may be reduced by 12% ± 53% and 20% ± 45% in 2080-2099 relative to 1980-1999 for the A1B and A2 scenarios, respectively. Likewise, results show that reliability and resiliency of the water system will tend to decrease; consequently, the vulnerability of the system increases over time. Proposed adaptation measures could make the system more reliable and less vulnerable in meeting water demands for irrigation and municipal uses. / text

Mudanças climáticas podem afetar a distribuição espacial e temporal das variáveis hidrológicas, tendo como consequências alterações nos regimes de precipitação e vazão dos rios. Aumentos ou reduções no volume de escoamento de uma bacia hidrográfica podem, por exemplo, produzir danos aos ecossistemas, afetar a produção de alimentos, abastecimento de água, navegação e geração de energia. Atualmente buscam-se relações que permitam entender os processos de mudanças climáticas a fim avaliar os impactos e mitigá-los, assim como avaliar as incertezas inerentes ao processo de modelagem hidrológica de tais mudanças. Neste contexto este trabalho apresenta uma metodologia de quantificação e análise de incertezas para estudos de mudanças climáticas, tomando como estudo de caso a bacia hidrográfica do Rio Uruguai (BHRU) com área aproximada de 110,000 Km². Para tanto três fontes de incerteza foram analisadas e comparadas: o modelo hidrológico, técnicas de remoção de viés e modelos climáticos. O modelo hidrológico MGB-IPH foi avaliado quanto ao processo de parametrização, utilizando diferentes períodos de simulação para calibração: (i) Período de calibração 1 – MGB/P1: representando a série completa de observações de 1960-1990 com verificação no período de 1992-1999; (ii) Período de calibração 2 - MGB/P2: calibração em período seco e verificação de período de cheias (iii) Período de calibração 3 – MGB/P3: calibração em período característico de cheias e verificação de período de estiagem. Três diferentes técnicas de remoção de viés foram aplicadas para analisar o grau de incerteza que a escolha de um determinado método de correção pode agregar ao resultado final: (i) RV1 - Técnica de Mapeamento Quantil-Quantil; (ii) RV2 - Técnica de Escalonamento Linear e (iii) RV3 - Técnica Delta change. Os modelos climáticos globais (GMC’s) foram analisados quanto a sua estrutura, comparando projeções de cinco diferentes modelos: MPEH5 (ECHAM5/MPIOM), GFCM21 (GFDL-CM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Adicionalmente, também foram analisadas as projeções climáticas de cinco diferentes versões do modelo climático regional (RCM) ETA/CPTEC: CT20, CT40, LOW, MID e HIGH. Inicialmente os resultados das simulações provenientes de cada uma destas fontes foram comparados de maneira isolada e em seguida de maneira combinada. Portanto, a metodologia foi dividida em Etapa (1) e Etapa (2). A Etapa (1) teve por objetivo responder a seguinte pergunta: Qual dentre as fontes de incerteza selecionadas agrega maior variação ao resultado final? Ou seja, qual destas fontes propaga maior incerteza em termos de impactos de mudanças climáticas na BHRU? Os resultados obtidos por cada uma das fontes de incerteza foram comparados em termos de anomalias de vazões médias de longo período (QMLP), máximas e mínimas anuais. Na Etapa (2) foi realizada a análise total de incerteza, ou seja, a análise combinada dos resultados obtidos na Etapa (1). As anomalias de vazões foram apresentadas utilizando as curvas de distribuição acumulada (CDF’s) e a incerteza total expressa pela diferença entre os percentis 5% e 95%. Considerando os resultados obtidos para as vazões médias de longo período (QMLP), as fontes podem ser ordenadas de forma decrescente, em relção ao grau de incerteza que propagam: modelos climáticos globais > modelos climáticos regionais > técnicas de remoção de viés > modelo hidrológico. Para as vazões extremas os RCM’s apresentam as maiores variações de anomalias se comparadas às dos modelos hidrológicos e técnicas de remoção de viés, inclusive para ambos os extremos, máximos e mínimos. Esta variação se dá principalmente, pelos resultados de LOW e MID. Estas informações podem ajudar os gestores e tomadores de decisão no adequado gerenciamento e planejamento dos recursos hídricos sob condições de mudanças climáticas, assim como o entendimento da incerteza associada. / Climate change can affect the spatial and temporal distribution of hydrological variables, with the consequences of changes in precipitation regimes and river flows. Increase or decrease the flow of rivers, for example, can cause damage to ecosystems, affecting food production, water supply, navigation and power generation. Currently seeking to relationships that allow understand climate change processes in order to assess the impacts and mitigate them, and assess the uncertainties inherent in hydrologic modeling process of such climate change. This thesis aimed at the development of a methodology for quantification and analysis of uncertainties for climate change studies in hydrology , taking as a case study the basin of the Uruguay River (BHRU) with a drainage area near 110,000 km². For that three sources of uncertainty were analyzed and compared: the hydrologic model, bias removal techniques and climate models. The hydrological model MGB-IPH was evaluated for parameterization, using different simulation periods for calibration: (i) MGB /P1: full range with calibration period (1960-1990) and validate (1992-1999); (ii) MGB / P2: calibrated in the period of dry and validated in the flood season (iii) MGB/P3: calibrated in the period of floods and validated in the dry season. Three different bias correction methods were applied to analyze the degree of uncertainty that the choice of a particular method of correction can add to the final result: (i) RV1 - Quantil-Quantil Mapping; (ii) RV2 - Linear Scaling, and (iii) RV3 - Delta Change Technique. Global climate models (GMC's) were analyzed for their structure, comparing projections of five different models: MPEH5 (ECHAM5/MPI-OM), GFCM21 (GFDLCM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Additionaly, climate projections from five different versions of the regional climate model (RCM) ETA / CPTEC were also analyzed: CT20, CT40, LOW, MID e HIGH. Initially the simulation results from each of the sources of uncertainty were compared individually (single propagation) and then in a combined way (multi propagation). Therefore, the methodology was divided in Step (1) and Step (2). Step (1) aimed to answer: Which of the selected sources of uncertainty adds more variation to the final result? Which of these sources propagates greater uncertainty in terms of impacts of climate change on BHRU? The results for each of the sources of uncertainty were compared in terms of long-term mean flow (QMLP), maximum and minimum annual flow. In Step (2) total uncertainty analysis was performed, therefore the combined analysis of the results obtained in Step (1). The anomalies in discharge were presented using the cumulative distribution function (CDF's) and the total uncertainty expressed by the difference between the percentiles 5% and 95%. Throughout the application of the proposed methodology it was concluded that: (i) for the extremes (maximum and minimum) annual discharges the largest source of uncertainty are the projections of the RCM's, followed by the the bias removal technique and finally the hydrological model; (ii) for the QMLP the largest source of uncertainty are followed global climate models, then the regional climate models. This information can help managers and decision makers in the proper management and planning of water resources under climate change conditions, as well as the understanding of the associated uncertainty.

Mudanças climáticas podem afetar a distribuição espacial e temporal das variáveis hidrológicas, tendo como consequências alterações nos regimes de precipitação e vazão dos rios. Aumentos ou reduções no volume de escoamento de uma bacia hidrográfica podem, por exemplo, produzir danos aos ecossistemas, afetar a produção de alimentos, abastecimento de água, navegação e geração de energia. Atualmente buscam-se relações que permitam entender os processos de mudanças climáticas a fim avaliar os impactos e mitigá-los, assim como avaliar as incertezas inerentes ao processo de modelagem hidrológica de tais mudanças. Neste contexto este trabalho apresenta uma metodologia de quantificação e análise de incertezas para estudos de mudanças climáticas, tomando como estudo de caso a bacia hidrográfica do Rio Uruguai (BHRU) com área aproximada de 110,000 Km². Para tanto três fontes de incerteza foram analisadas e comparadas: o modelo hidrológico, técnicas de remoção de viés e modelos climáticos. O modelo hidrológico MGB-IPH foi avaliado quanto ao processo de parametrização, utilizando diferentes períodos de simulação para calibração: (i) Período de calibração 1 – MGB/P1: representando a série completa de observações de 1960-1990 com verificação no período de 1992-1999; (ii) Período de calibração 2 - MGB/P2: calibração em período seco e verificação de período de cheias (iii) Período de calibração 3 – MGB/P3: calibração em período característico de cheias e verificação de período de estiagem. Três diferentes técnicas de remoção de viés foram aplicadas para analisar o grau de incerteza que a escolha de um determinado método de correção pode agregar ao resultado final: (i) RV1 - Técnica de Mapeamento Quantil-Quantil; (ii) RV2 - Técnica de Escalonamento Linear e (iii) RV3 - Técnica Delta change. Os modelos climáticos globais (GMC’s) foram analisados quanto a sua estrutura, comparando projeções de cinco diferentes modelos: MPEH5 (ECHAM5/MPIOM), GFCM21 (GFDL-CM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Adicionalmente, também foram analisadas as projeções climáticas de cinco diferentes versões do modelo climático regional (RCM) ETA/CPTEC: CT20, CT40, LOW, MID e HIGH. Inicialmente os resultados das simulações provenientes de cada uma destas fontes foram comparados de maneira isolada e em seguida de maneira combinada. Portanto, a metodologia foi dividida em Etapa (1) e Etapa (2). A Etapa (1) teve por objetivo responder a seguinte pergunta: Qual dentre as fontes de incerteza selecionadas agrega maior variação ao resultado final? Ou seja, qual destas fontes propaga maior incerteza em termos de impactos de mudanças climáticas na BHRU? Os resultados obtidos por cada uma das fontes de incerteza foram comparados em termos de anomalias de vazões médias de longo período (QMLP), máximas e mínimas anuais. Na Etapa (2) foi realizada a análise total de incerteza, ou seja, a análise combinada dos resultados obtidos na Etapa (1). As anomalias de vazões foram apresentadas utilizando as curvas de distribuição acumulada (CDF’s) e a incerteza total expressa pela diferença entre os percentis 5% e 95%. Considerando os resultados obtidos para as vazões médias de longo período (QMLP), as fontes podem ser ordenadas de forma decrescente, em relção ao grau de incerteza que propagam: modelos climáticos globais > modelos climáticos regionais > técnicas de remoção de viés > modelo hidrológico. Para as vazões extremas os RCM’s apresentam as maiores variações de anomalias se comparadas às dos modelos hidrológicos e técnicas de remoção de viés, inclusive para ambos os extremos, máximos e mínimos. Esta variação se dá principalmente, pelos resultados de LOW e MID. Estas informações podem ajudar os gestores e tomadores de decisão no adequado gerenciamento e planejamento dos recursos hídricos sob condições de mudanças climáticas, assim como o entendimento da incerteza associada. / Climate change can affect the spatial and temporal distribution of hydrological variables, with the consequences of changes in precipitation regimes and river flows. Increase or decrease the flow of rivers, for example, can cause damage to ecosystems, affecting food production, water supply, navigation and power generation. Currently seeking to relationships that allow understand climate change processes in order to assess the impacts and mitigate them, and assess the uncertainties inherent in hydrologic modeling process of such climate change. This thesis aimed at the development of a methodology for quantification and analysis of uncertainties for climate change studies in hydrology , taking as a case study the basin of the Uruguay River (BHRU) with a drainage area near 110,000 km². For that three sources of uncertainty were analyzed and compared: the hydrologic model, bias removal techniques and climate models. The hydrological model MGB-IPH was evaluated for parameterization, using different simulation periods for calibration: (i) MGB /P1: full range with calibration period (1960-1990) and validate (1992-1999); (ii) MGB / P2: calibrated in the period of dry and validated in the flood season (iii) MGB/P3: calibrated in the period of floods and validated in the dry season. Three different bias correction methods were applied to analyze the degree of uncertainty that the choice of a particular method of correction can add to the final result: (i) RV1 - Quantil-Quantil Mapping; (ii) RV2 - Linear Scaling, and (iii) RV3 - Delta Change Technique. Global climate models (GMC's) were analyzed for their structure, comparing projections of five different models: MPEH5 (ECHAM5/MPI-OM), GFCM21 (GFDLCM2.1), MRCGCM (MRI-CGCM2.3.2), HADCM3 (UKMO-HadCM3) e NCCCSM (CCSM3). Additionaly, climate projections from five different versions of the regional climate model (RCM) ETA / CPTEC were also analyzed: CT20, CT40, LOW, MID e HIGH. Initially the simulation results from each of the sources of uncertainty were compared individually (single propagation) and then in a combined way (multi propagation). Therefore, the methodology was divided in Step (1) and Step (2). Step (1) aimed to answer: Which of the selected sources of uncertainty adds more variation to the final result? Which of these sources propagates greater uncertainty in terms of impacts of climate change on BHRU? The results for each of the sources of uncertainty were compared in terms of long-term mean flow (QMLP), maximum and minimum annual flow. In Step (2) total uncertainty analysis was performed, therefore the combined analysis of the results obtained in Step (1). The anomalies in discharge were presented using the cumulative distribution function (CDF's) and the total uncertainty expressed by the difference between the percentiles 5% and 95%. Throughout the application of the proposed methodology it was concluded that: (i) for the extremes (maximum and minimum) annual discharges the largest source of uncertainty are the projections of the RCM's, followed by the the bias removal technique and finally the hydrological model; (ii) for the QMLP the largest source of uncertainty are followed global climate models, then the regional climate models. This information can help managers and decision makers in the proper management and planning of water resources under climate change conditions, as well as the understanding of the associated uncertainty.

Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-07-04T11:51:54Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Mestrado Ráurium versão final.pdf: 6757441 bytes, checksum: b3d2956882bd467a5f2fcb592d7f079c (MD5) / Made available in DSpace on 2016-07-04T11:51:54Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) Dissertação Mestrado Ráurium versão final.pdf: 6757441 bytes, checksum: b3d2956882bd467a5f2fcb592d7f079c (MD5) Previous issue date: 2015-10-26 / A costa litorânea do Estado de Pernambuco no Nordeste do Brasil é dotada por várias bacias hidrográficas onde pode-se destacar a bacia do rio Pirapama, que abrange sete municípios e é constituída dos principais mananciais de abastecimento da Região Metropolitana do Recife. O presente estudo apresenta a simulação da disponibilidade hídrica da bacia do Pirapama, e propõe regras de operação para os reservatórios de abastecimento hídrico inclusos na bacia, levando-se em conta a variabilidade climática com ênfase a evitar as condições de racionamento e colapso do reservatório Pirapama frente aos eventos de seca. A partir do modelo hidrológico SMAP foi gerada a série de vazões em 7 sub-bacias da bacia do rio Pirapama abrangendo o período de 1933 a 2014. Essa série de dados foi inserida no modelo de simulação AcquaNet que permitiu elaborar a rede de fluxo representativa da bacia e simular a disponibilidade hídrica nas suas sub-bacias e reservatórios estratégicos. Embasadas em metodologias distintas, foram apresentadas duas propostas de regras de operação para o reservatório Pirapama e uma para o reservatório Sicupema. A primeira proposta, as curvas-guia, consistiu no zoneamento do volume útil do reservatório de acordo com o estado de severidade de seca, sendo os eventos de seca quantificados através do índice de escoamento padronizado SRI (Standardized Runoff Index). A segunda proposta foi a simulação das Curvas de Aversão a Risco – CAR através do AcquaNet, que possibilitou analisar o comportamento do reservatório para várias vazões de retiradas, tendo por base as afluências no biênio mais critico da série simulada. Para o reservatório Sicupema, foram realizadas simulações no AcquaNet, estabelecendo regras de operação através do volume meta. Os resultados mostraram um ajuste satisfatório na calibração e validação do modelo hidrológico, assim como, na análise comparativa dos volumes simulados e monitorados do reservatório Pirapama. O comportamento dos 82 anos simulados no reservatório Pirapama demonstrou a necessidade de se alterar as regras de operação atuais, pois o mesmo esteve por 5 anos e meio nas condições de racionamento ou colapso. As regras de operação propostas, quando aplicadas ao reservatório Pirapama, se mostraram eficientes e eficazes, eliminando o risco de colapso, e reduzindo a condição de racionamento de 39 para 4 e 7 meses, nas curvas-guia e CAR, respectivamente, constituindo numa importante ferramenta de tomada de decisão na gestão do maior sistema de abastecimento do Estado de Pernambuco. / The coastline of the state of Pernambuco in northeastern Brazil is endowed by various river basins where we can highlight the basin of the Pirapama river, covering seven cities and is responsible for most of the supply of the Metropolitan Region of Recife.This study presents the simulation of water availability of Pirapama River basin, located in the coastline of the state of Pernambuco in northeastern Brazil, and proposes operating rules for water supply reservoirs included in the basin, taking into account the variability climate with emphasis on avoiding rationing conditions and collapse of Pirapama reservoir forward to drought events. From the hydrological model was generated series of discharges in 7 sub-basins of Pirapama river basin in period from 1933 to 2014.This data set was inserted into the simulation model AcquaNet which established the network of representative outflow of the basin and simulate water availability in their sub-basins and strategic reservoirs. Based on different methodologies were presented two proposals for operating rules for Pirapama reservoir and one for Sicupema dam. The first proposal, the rules curves, consisted of the zoning of the useful volume of the reservoir according to drought severity state, and drought events quantified by Standardized Runoff Index- SRI. The second proposal was the simulation of Aversion to Risk Curves - CAR through AcquaNet, which made it possible to analyze the reservoir behavior for several withdrawals flows, based on two years of critical inflows simulated series. For Sicupema reservoir simulations were performed in AcquaNet, establishing operating rules by volume goal. The results showed a satisfactory adjustment in the calibration and validation of hydrological model, as well as the comparative analysis of the simulated volumes and monitored the Pirapama reservoir. The behavior of the simulated 82 years in Pirapama reservoir demonstrated the need to change the current operating rules, because it was for 5 years and a half in the rationing conditions or collapse. The rules of operation proposals when applied to Pirapama reservoir, were efficient and effective, eliminating the risk of collapse, and reducing 39 rationing condition for 4 and 7 months, the guide curves and CAR, respectively, constituting an important decision-making tool in managing the largest supply system of the State of Pernambuco.

Made available in DSpace on 2014-07-29T15:01:43Z (GMT). No. of bitstreams: 1 dissertacao claudio r da silva 2009.pdf: 998225 bytes, checksum: a40670e10535eb078839ce755dc77895 (MD5) Previous issue date: 2009-08-28 / This study presents the results of the analysis of the effect of the spatial scale in the hydrologic modeling. Nine watersheds were delimited in three different spatial scales: small (Capão da Onça River Basin), middle (Areias River Basin) and large (Corrente River Basin). The physiographic characteristics, area, length of the main river and slope of the river were obtained from digital cartographic maps in the three available scales for Goiás, 1:1.000.000, 1:250.000 and 1:100.000, using tools of Geographic Information Systems. The physical data of the basins were used as input in the hydrologic model - HEC HMS version 3.3 - developed by Hydrologic Engineering Center of the U.S. Army Corps of Engineers, projected to simulate the precipitation-runoff process in a watershed. After the simulation procedures and calibration of the model, the study shows that data obtained from different cartographic scales little influence the final result of the modeling in the three analyzed spatial scales. It was also evidenced that the modeling presented better results in the middle scale with a better adjustment between the observed and calculated hydrographs. / Este estudo apresenta os resultados da análise do efeito da escala espacial na modelagem hidrológica. Para isto foram delimitadas bacias hidrográficas em três diferentes escalas espaciais: pequena (Bacia do Córrego Capão da Onça), média (Bacia do Rio Areias) e grande (Bacia do Rio Corrente), em Goiás e no Distrito Federal. As características fisiográficas, área, comprimento do rio principal e desnível do rio foram obtidas a partir de bases cartográficas digitais nas três escalas disponíveis, 1:1.000.000, 1:250.000 e 1:100.000, utilizando-se ferramentas de Sistemas de Informações Geográficas. Os dados físicos das bacias foram utilizados como dados de entrada no modelo hidrológico HEC HMS versão 3.3 - desenvolvido pelo Hydrologic Engineering Center of the U.S. Army Corps of Engineers, projetado para simular o processo chuva-vazão em bacias hidrográficas. Após os procedimentos de simulação e de calibração do modelo, o estudo mostra que dados obtidos a partir de diferentes escalas cartográficas pouco influenciam o resultado final da modelagem nas três escalas espaciais analisadas. Foi evidenciado, também, que a modelagem apresentou melhores resultados na média escala com um melhor ajuste entre as hidrógrafas observadas e calculadas

<p>The presented work quantifies the impacts of inundated land area (ILA) on streamflow and crop development in the Upper Midwest, which is experiencing a changing climate with observed increases in temperature and precipitation. Quantitative information is needed to understand how upland and downstream stakeholders are impacted by ILA; yet the temporal and spatial extent of ILA and the impact of water storage on flood propagation is poorly understood. Excess water in low gradient agricultural landscapes resulting in ILA can have opposing impacts. The ILA can negatively impact crop development causing financial loss from a reduction or total loss in yield while conversely, ILA can also benefit downstream stakeholders by preventing flood damage from the temporary surface storage that slows water movement into channels. This research evaluates the effects of ILA on streamflow and crop development by leveraging the utility of remotely sensed observations and models.</p><p> </p><p>The influence of ILA on streamflow is investigated in the Red River basin, a predominantly agricultural basin with a history of damaging flood events. An inundation depth-area (IDA) parameterization was developed to parameterize the ILA in a hydrologic model, the Variable Infiltration Capacity (VIC) model, using remotely sensed observations from the MODIS Near Real-Time Global Flood Mapping product and discharge data. The IDA parameterization was developed in a subcatchment of the Red River basin and compared with simulation scenarios that did and did not represent ILA. The model performance of simulated discharge and ILA were evaluated, where the IDA parameterization outperformed the control scenarios. In addition, the simulation results using the IDA parameterization were able to explain the dominant runoff generation mechanism during the winter-spring and summer-fall seasons. The IDA parameterization was extended to the Red River basin to analyze the effects of ILA on the timing and magnitude of peak flow events where observed discharge revealed an increasing trend and magnitude of summer peak flow events. The results also showed that the occurrence of peak flow events is shifting from unimodal to bimodal structure, where peak flow events are dominant in the spring and summer seasons. By simulating ILA in the VIC model, the shift in occurrence of peak flow events and magnitude are better represented compared to simulations not representing ILA.</p><p> </p><p>The impacts of ILA on crop development are investigated on soybean fields in west-central Indiana using proximal remote sensing from unmanned aerial systems (UASs). Models sensitive to ILA were developed from the in-situ and UAS data at the plot scale to estimate biomass and percent of expected yield between the R4-R6 stages at the field scale. Low estimates of biomass and percent of expected yield were associated with mapped observations of ILA. The estimated biomass and percent of expected yield were useful early indicators to identify soybean impacted by excess water at the field scale. The models were applied to satellite imagery to quantify the impacts of ILA on soybean development over larger areas and multiple years. The estimated biomass and percent of expected yield correlated well with the observed data, where low model estimates were also associated with mapped observations of ILA and periods of excessive rainfall. The results of the work link the impacts of ILA on streamflow and crop development, and why it is important to quantify both in a changing climate. By representing ILA in hydrologic models, we can improve simulated streamflow and ILA and represent dominant physical process that influence hydrologic responses and represent shift and seasonal occurrence of peak flow events. In the summer season, where there is an increased occurrence of peak flow events, it is important to understand the impacts of ILA on crop development. By quantifying the impacts of ILA on soybean development we can analyze the spatiotemporal impacts of excess water on soybean development and provide stakeholders with early assessments of expected yield which can help improvement management decisions.</p>

No description available.

The simple accumulation-based network identification method (ANIM) in a raster Geographic Information System (GIS) posed by O'Callaghan and Mark (1984) has been criticized for producing a spatially uniform drainage density (Tarboton 2002) at the watershed scale. This criticism casts doubt on the use of ANIMs for deriving properties such as overland flow length for nonpoint source pollution models, without calibrating the accumulation threshold value. However, the basic assumption that underlies ANIMs is that convergent topography will yield a more rapid accumulation of cells, and thus, more extensive flow networks, with divergent, or planar terrain yielding sparser networks. Previous studies have focused on networks that are coarser than the hill-slope scale, and have relied upon visual inspection of drainage networks to suggest that ANIMs lack the ability to produce diverse networks. In this study overland flow lengths were calculated on a sub-watershed basis, with standard deviation, and range calculated for sub-watershed populations as a means of quantifying the diversity of overland flow lengths produced by ANIM at the hill slope scale. Linear regression and Spearman ranking analyses were used to determine if the methods represented trends in overland flow length as suggested by manual delineation of contour lines. Three ANIMs were analyzed: the flow accumulation method (O'Callaghan and Mark, 1984), the terrain curvature method (Tarboton, 2000) and the ridge accumulation method (introduced in this study). All three methods were shown to produce non-zero standard deviations and ranges using a single support area threshold, with the terrain curvature method producing the most diverse networks, followed by the ridge accumulation method, and then the flow accumulation method. At an analysis unit size of 20 ha, the terrain curvature method produced a standard deviation that was most similar to those suggested by the contour crenulations, -13.5%, followed by the ridge accumulation method, -21.5%, and the flow accumulation method, -61.6%. The ridge accumulation produced the most similar range, -19.1%, followed by terrain curvature, -24.9%, and flow accumulation, -65.4%. While the flow accumulation networks had a much narrower range of predicted flow lengths, it had the highest Spearman ranking coefficient, Rs=0.722, and linear regression coefficient, R2=0.602. The terrain curvature method was second, Rs=0.641, R2=0.469, and then ridge accumulation, Rs=0.602, R2=0.490. For all methods, as threshold values were varied, areas of dissimilar morphology (as evidenced by the common stream metric stream frequency) experienced changes in overland flow lengths at different rates. This results in an inconsistency in ranking of sub-watersheds at different thresholds. When thresholds were varied to produce average overland flow lengths from 75 m to 150 m, the terrain curvature method showed the lowest incidence of rank change, 16.05%, followed by the ridge accumulation method, 16.73%, then flow accumulation, 25.18%. The results of this investigation suggest that for all three methods, a causal relationship exists between threshold area, underlying morphology, and predicted overland flow length. This causal relationship enables ANIMs to represent contour network trends in overland flow length with a single threshold value, but also results in the introduction of rank change error as threshold values are varied. Calibration of threshold value (varying threshold in order to better match observed overland flow lengths) is an effective means of increasing the accuracy of ANIM predictions, and may be necessary when comparing areas with different stream frequencies. It was shown that the flow accumulation method produces less diverse networks than the terrain curvature and ridge accumulation methods. However, the results of rank and regression analyses suggest that further investigation is required to determine if these more diverse ANIM are in fact more accurate than the flow accumulation method. / Master of Science

Submitted by Cássia Santos (cassia.bcufg@gmail.com) on 2014-08-22T15:59:53Z No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Nayda Rocha.pdf: 4573500 bytes, checksum: b80c49f66c8b1cd85865a2ad652e95f0 (MD5) / Made available in DSpace on 2014-08-22T15:59:53Z (GMT). No. of bitstreams: 2 license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Dissertação - Nayda Rocha.pdf: 4573500 bytes, checksum: b80c49f66c8b1cd85865a2ad652e95f0 (MD5) Previous issue date: 2013-08-09 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The effect of urbanization and insufficient supervision of the use of natural resources by the government has led to increasing degradation of the environment in Brazil. This can be seen by the suppression of riparian vegetation, which is essential for the survival and maintenance of the quality of water sources. In this sense, the actions of development of land, housing provision and sanitation in Brazil must have, among other objectives, to ensure an environment conducive to ecosystems and human life support. This research aimed to identify the characteristics of occupation of Córrego Samambaia Basin in Goiânia, used for public water supply, correlating land use with hydrological processes. The methodology adopted consisted in: identifying the theoretical framework from literature and choose a basin to develop a case study; select and gather information from the object of study contained in published documents, restricted texts, satellite imagery, site visits, to generate the necessary data for modeling, and apply the hydrologic model Storm Water Management Model (SWMM) in three distinct periods and three proposed scenarios to understand the hydrological responses in the study area due to different levels of human occupation. The results obtained with this research indicate that the hydrological watershed responses can vary widely if the waterproofing process continue to increase. Results shown that between 1992 (with impervious area of 7%) and the proposed Scenario 3 (with impervious area of 70%) the increase in runoff is approximately 24 times while the infiltration becomes 70% smaller. If the basin achieves an index greater than 50% of impervious area, it will probably become unviable for public supply purposes. In order to preserve the watershed for its main purpose to continue supplying the municipality this study proposes an appropriated urban planning, with the construction of a Linear Park along the creek and the adoption of new levels of urban occupation. This planning model may be used in other urban basins, taking into account the characteristics of each site. / O efeito da urbanização e a insuficiente fiscalização do uso dos recursos naturais pelo poder público têm provocado crescente degradação do meio ambiente no Brasil. Isto pode ser constatado na supressão da vegetação ciliar, indispensável para a sobrevivência e manutenção da qualidade dos mananciais. Neste sentido, as ações de parcelamento do solo, provisão habitacional e saneamento no país devem ter, entre outros objetivos, o de assegurar um meio ambiente favorável aos ecossistemas e à vida humana. Esta dissertação teve como objetivo principal identificar as características de ocupação da bacia hidrográfica do Córrego Samambaia em Goiânia, utilizada para abastecimento público de água, correlacionando o uso do solo com os processos hidrológicos. A metodologia adotada consistiu em: identificar o referencial teórico a partir de pesquisa bibliográfica e escolher uma bacia para estudo de caso; selecionar e reunir informações do objeto de estudo contidas em documentos publicados, textos restritos, imagens de satélite, visitas in loco, para a geração dos dados necessários para realizar a modelagem; e aplicar o modelo hidrológico Storm Water Management Model (SWMM) em três períodos distintos e outros três cenários propostos para se conhecer as respostas hidrológicas na área de estudo frente a diferentes níveis de intervenção e ocupação urbana. Os resultados obtidos com esta pesquisa indicam que a bacia pode apresentar grandes variações hidrológicas caso o processo de impermeabilização continue aumentando. Com relação ao escoamento superficial na bacia, entre 1992 (com área impermeável de 7%) e o Cenário 3 proposto (com área impermeável de 70%) o aumento é de aproximadamente 24 vezes enquanto no mesmo período a infiltração tornou-se 70% menor. Se a bacia obtiver um índice maior que 50% de área impermeável, provavelmente irá se tornar inviável ao abastecimento público. Para que ela continue abastecendo o município, propõe-se neste estudo um planejamento urbano adequado, com a construção de um Parque Linear ao longo do córrego e a adoção de novos índices de ocupação urbana. Este modelo de planejamento poderá ser utilizado em outras bacias urbanas, levando em consideração as características de cada local.

FundaÃÃo de Amparo à Pesquisa do Estado do Cearà / A premissa pelo uso racional da Ãgua tem demandado informaÃÃes em escalas de espaÃo e tempo cada vez menores. Neste estudo investiga-se a sensibilidade da simulaÃÃo climÃtica de um downscaling dinÃmico de precipitaÃÃo (1971-2000) acoplado a um modelo chuva-vazÃo e sua aplicaÃÃo na operaÃÃo de um reservatÃrio hÃdrico na regiÃo semi-Ãrida do Estado do CearÃ. Foi dada uma Ãnfase a escala intrasazonal (abaixo de um mÃs) em anos de contrastess climÃticos classificados como de La NiÃa, El NiÃo e Normais ocorridos no Oceano PacÃfico Tropical. Foram usados o modelo de circulaÃÃo geral da atmosfera ECHAM4.5, e o modelo regional, denominado de Modelo Regional Espectral (MRE), versÃo 97, do National Centers for Atmospheric Prediction- NCEP. O MRE foi aninhado aos dados simulados pelo ECHAM4.5 tendo como condiÃÃo de contorno a Temperatura da SuperfÃcie do Mar observada no perÃodo de janeiro a junho de 1971-2000. Para a estimativa de vazÃo foi usado o modelo SMAP. Entre os principais resultados citam-se: apÃs a correÃÃo pela tÃcnica das Probability Density Functions (PDFs), os dados simulados pelo MRE, conseguiram capturar melhor a variabilidade diÃria da precipitaÃÃo no posto fluviomÃtrico de Iguatu, mÃdia entre 01 de janeiro e 30 de junho. A explicaÃÃo da variÃncia antes da correÃÃo foi de menos de 5%, passando a em torno de 40% apÃs as correÃÃes pelas PDFs. As simulaÃÃes de vazÃo, analisadas pela explicaÃÃo da variÃncia, coeficiente de correlaÃÃo ao quadrado, mostraram que hà um ganho de explicaÃÃo desta variÃncia de duas ou mais vezes, quando se compara esta explicaÃÃo em relaÃÃo à precipitaÃÃo. Este ganho foi observado tanto para perÃodos diÃrios, pentadais e quinzenais e para todo o perÃodo (1971-2000). Mais de 70% do sinal das anomalias pentadais de vazÃo foram bem simulados. SimulaÃÃes de volume de um reservatÃrio hipotÃtico (com as caracterÃsticas do AÃude OrÃs), com volume inicial V0=0,25k (capacidade mÃxima - 1940 hm3), 0,50k e 0,75k, mostraram que hà potencial do uso dessa informaÃÃo de precipitaÃÃo em cascata com o modelo chuva-vazÃo, em particular para os anos classificados como Normais. A explicaÃÃo da variÃncia entre os volumes simulados e observados diÃrios, para os meses de janeiro a junho, para estes anos Normais tiveram resultados mais expressivos. Esta ficou torno ou mais de 80%. Em sÃntese, os resultados evidenciaram o potencial de uso da simulaÃÃo acoplada da modelagem dinÃmica atmosfÃrica com a modelagem hidrolÃgica associada à operaÃÃo do reservatÃrio. / The premiss for the rational use of water has demanded information on smaller space and time scales. This study investigates the sensitivity of climate simulation of a dynamic downscaling of precipitation (1971-2000) coupled to a rain-flow model and its application to the operation of a water reservoir in the semi-arid region of Cearà State. Emphasis was given to intra seasonal scale (smaller than a month) in years of climatic contrasts classified with La NiÃa, El NiÃo and Normals (averaged) in the Tropical Pacific Ocean. We used atmospheric general circulation model ECHAM4.5, and the Regional Spectral Model (RMS), version 97 of National Center for Atmospheric Prediction-NCEP. The RSM was nested with data simulated by ECHAM4.5, taking as boundary condition the sea surface temperature observed in the period January to June 1971-2000. For estimating streamflow we rate used the SMAP model. Results show that after the technique of Probability Density Functions (PDFs) correction, the simulation by RSM, best captured daily variability of precipitation at fluviometric post of Iguatu, average, from 01 January to 30 June. The explaned variance before the correction was less than 5%, rising to around 40% after the correction by PDFs. The simulations of streamflow, analyzed by the explaned variance, square of correlation coefficient, shows that there is a two or more gain of explaned this variance, as compared with explanation to streamflow in relation to rainfall. This gain is observed for all periods (daily and accumulated five and fifteen days), and for the entire period (1971-2000). More than 70% pentads anomalies of stramflow were well simulated. Simulations of volume of a hypothetical reservoir (with the characteristics of the OrÃs Dam) with initial volum V0 = 0.25k ( maxim capacity - 1940 hm3), 0.50k and 0.75k, showed that there is the potential use of that cascade information of precipitation with rain-flow model, in particular for averaged years classified. The explanation of the variance between simulated and observed daily volumes for the months of January to June, for these years Normal results was more expressive. This was about 80%. In summary, the results showed the potential for use of coupled simulation model between atmospheric modeling water associated with the reservoir operation.