José Nilson B. Campos

Paradigms and Public Policies on Drought in Northeast Brazil: A Historical Perspective

AbstractThis paper describes the evolution of drought-related public policies in Northeast Brazil (NEB). Using a historical approach, we show that the evolution of public policy has not been characterized by abrupt shifts, but has instead been shaped through debates between renowned intellectuals. The resulting public policies formed a hydrological infrastructure that delivers clean water needed for robust economic activity. However, outcomes of the 2012–2013 drought show that populations that depend on rain fed agriculture are as vulnerable to drought as they were at the start of the 20th century. Although government, social, and emergency programs have aided drought victims, drought analysts agree that rain fed agriculture has remained vulnerable since drought policies were first formulated. Drought policies formulate integrated water resources management (IWRM) strategies that are geared toward supplying safe drinking water, and debates surrounding the IWRM paradigm have been affected by outcomes of major international events such as the World Water Forum.

An Historical Perspective on the Administration of Water in Brazil

Abstract This article focuses on two instruments of water resources management—charging for water and reallocation of water use through a water market. Charging for water in nature has been practiced for centuries in some cases. On the other hand, a culture of free access to water was dominant in most countries during ancient times. An historical review of the charging of water and its administration is presented. The article covers the time of ancient Rome to the present. A current example is the model practiced in the semi-arid region of Ceará State in northeast Brazil. Regarding water use reallocation by a water market, as an alternative to improve water efficiency, the experience presented comes from the south of Ceará State one century ago. Based on past experience, the article then presents a model to implement a water market bounded in space to an irrigation district, and in time to periods of water deficit in reservoirs. Six prerequisites of market-based transfers of water are analyzed, and it is shown that in the proposed model they can be addressed.

Secas e políticas públicas no semiárido: ideias, pensadores e períodos

O artigo analisa a evolucao das politicas publicas contra as secas praticadas no Nordeste a partir do periodo Colonial. Uma proposta de periodizacao com base nas politicas predominantes e apresentada. A periodizacao e organizada em cinco fases: 1) defrontando-se com as secas; 2) a busca do conhecimento; 3) a hidraulica da solucao; 4) o desenvolvimento regional; 5) a gestao das aguas e o desenvolvimento sustentavel. As logicas e os pensamentos dos principais intelectuais que deram suporte a essas politicas sao objetos de analise e discussao.

Reservoir Management Using Coupled Atmospheric and Hydrological Models: The Brazilian Semi-Arid Case

This study investigated the sensitivity of a dynamic downscaling atmospheric model system coupled with a rainfall-runoff model to hindcast an example of reservoir water management in the semi-arid region of Northeast Brazil (NEB). A regional atmospheric spectral model (RSM) is driven by the outputs of an atmospheric general circulation model (AGCM), itself forced by the observed sea surface temperature over the World Ocean. Daily precipitation simulated by the RSM was then used as the input to a hydrological rainfall-runoff model for the Upper Jaguaribe River Basin to estimate inflows at the Orós Reservoir in the state of Ceará. A hindcast analysis of precipitation was performed during the rainy season over NEB (January to June) from 1971 to 2000. The RSM captured the precipitation variability relatively well when a probability density function (PDF) was used to correct the numerical bias. Three hindcast series of inflow using (i) the observed rainfall, (ii) the simulated rainfall before the PDF correction, and (iii) the simulated rainfall after the PDF correction were performed during the study period and then compared to the series of observed inflow. The atmospheric-rainfall-runoff “cascade” model efficiency was evaluated by comparing the Orós Reservoir release decisions from different scenarios based on observed, simulated (RSM, RSM-PDF), and mean historical reservoir inflows. The cascade model has the potential, relatively well balanced during dry, normal or wet years, to be a useful tool to correctly forecast the decision managements of reservoirs in the semi-arid region of NEB. Additional progress in the numerical simulation is however necessary to improve the performance.

Um estudo inter-comparativo de previsão sazonal estatística-dinâmica de precipitação no nordeste do Brasil

Despite significant advances of the dynamic atmosphere models over the last decades of the 20th century, the empirical atmospheric models have been widely used due mostly to both its general applicability and its little dependence on the computational resources. This study is show comparison of precipitation simulation to Northeast Brazil (NEB) - 1971-2000 from large scale dynamical modeling and regional model (downscaling) and the forecast of empirical modeling (K-nearest-neighbor (k-NN). Were user the general circulation model ECHAM4.5 together two regional models, the Regional Spectral Model (RSM/97) from the National Centers for Atmospheric Prediction-NCEP and the Regional Atmospheric Model System (RAMS) developed at Colorado State University. The regional models were nested in ECHAM4.5, forced with the observed Sea Surface Temperature as a boundary condition, for the period from February to May. The results show that the empirical model presented a smaller absolute error than the dynamic models for the periods February to April (FMA) and March to May (MAM) in isolated areas of the north of Maranhao and Piaui states, west and south of Ceara, center-south of Piaui and west and northeast of Bahia state. Regarding model biases, ECHAM4.5 and the RSM/97 produced, to a large extent, a humid bias over large areas of NEB, however with an average precipitation for the northern sector of NEB (2oS-12oS and 45oW-37oW) close to the observations. RAMS and the analog method had a dominance of a dry bias over NEB, with precipitation totals below the observed values. The model skills (using the Heidke score) were evaluated for three categories Dry (S), Normal (N), Rainy (C), showed that the analogous method has low skills, between 0,1 and 0,3 in all categories, while dynamic models presented superior skills, with larger values for categories S and C (of the order of 0,4 the 0,5), exceeding 0,6 in some areas of the northern sector of NEB for category C as seen in the models ECHAM4.5 and RSM/97 models.

Conflitos por águas e alocação negociada: o caso do vale dos Carás no Ceará

The paper describes a water conflict for using the water regulated by the Thomas Osterne and Manoel reservoirs in Caras river basin in southern part of Ceara State. Along the river, farmers have built small dams to withdraw waters released in the river from the reservoirs. In times of droughts, the conflict settled in due to the retention of water in upstream that prevented it came to users of downstream. The article also describes the Ceara States institutional model and the way it deals with water conflicts. It is analyzed the practice of negotiating the water allocation as a strategy for conflict mediation. The main actors involved in conflict and its mediation were: users, technical water managers, prosecutors, political, and environmental institutions. As a result, it has been achieved, peacefully, the removal of earths dams that interfered in the free flow of water.

O Intervalo de Tempo para uma Máxima Previsiblidade da Precipitação sobre o Semiarido Brasileiro

This paper presents an evaluation of the climate forecast in the upper valley of the river Jaguaribe, State of Ceara-Brazil. The forecast was performed using the global circulation model (ECHAM 4.5) boundary conditions to the regional model (RAMS 6.0). The model simulates the monthly scale rainfall in order to aggregate it in the regional rainy season (January to June). We used the Heidke Skill Score (HSS) as a metric of forecast skill. The simulations were performed for the wet season, covering the period from 1979 to 2010. The HSS was calculated for intervals of 1, 2, 10, 15, 21, 30, 45, 60, 120 and 180 days in order to find the Time Interval of Maximum Predictability (ITEMP). The obtained curve, HSS vs. time, presented a maximum HSS of 0.62 for 45 days. This result indicates that climate prediction even with its limitations (initial data of soil moisture and used parameterization) could be an important tool for the reservoir management in Brasilian Semiarid region.

Calculation method for charging water on shrimp farming

The increase of global water demand has stimulated the application of water charging to seek its rational use. However, the establishment of the water tariff for a certain use is not an easy task, given that this tariff must have an elevated value, sufficient to encourage the rational use, but not so elevated, in a manner that compromises or prevents the development of production activities. The present study aimed to evaluate different water tariff values proposed and applied to the shrimp farming industry in Ceara, from 2003 to 2016, and analyze the sensitivity of the industry to these values. The analyses considered the productive performance of the shrimp farming observed by the producers, production costs for the activity, and incomes earned by the producers in 2008. The present study demonstrated that the only tariff value that makes the sector financially attractive is R

Trade-off between reservoir yield and evaporation losses as a function of lake morphology in semi-arid Brazil

1.00/1,000m3, a lower value than the one previously proposed by the state of Ceara (R

Uma aplicação de conjuntos difusos na otimização do prognóstico de consenso sazonal de chuva no Nordeste do Brasil

31.20/1,000m3), which was reduced in the following years. In this context, a model was developed to fix tariffs for shrimp farming, which considers the payment capacity of the entrepreneur and the production costs to cultivate shrimp.