Showing papers on "Water scarcity published in 2015"

Water Scarcity and Future Challenges for Food Production

Abstract: Present water shortage is one of the primary world issues, and according to climate change projections, it will be more critical in the future. Since water availability and accessibility are the most significant constraining factors for crop production, addressing this issue is indispensable for areas affected by water scarcity. Current and future issues related to “water scarcity” are reviewed in this paper so as to highlight the necessity of a more sustainable approach to water resource management. As a consequence of increasing water scarcity and drought, resulting from climate change, considerable water use for irrigation is expected to occur in the context of tough competition between agribusiness and other sectors of the economy. In addition, the estimated increment of the global population growth rate points out the inevitable increase of food demand in the future, with an immediate impact on farming water use. Since a noteworthy relationship exists between the water possessions of a country and the capacity for food production, assessing the irrigation needs is indispensable for water resource planning in order to meet food needs and avoid excessive water consumption.

The Potential Role of Neglected and Underutilised Crop Species as Future Crops under Water Scarce Conditions in Sub-Saharan Africa.

Abstract: Modern agricultural systems that promote cultivation of a very limited number of crop species have relegated indigenous crops to the status of neglected and underutilised crop species (NUCS). The complex interactions of water scarcity associated with climate change and variability in sub-Saharan Africa (SSA), and population pressure require innovative strategies to address food insecurity and undernourishment. Current research efforts have identified NUCS as having potential to reduce food and nutrition insecurity, particularly for resource poor households in SSA. This is because of their adaptability to low input agricultural systems and nutritional composition. However, what is required to promote NUCS is scientific research including agronomy, breeding, post-harvest handling and value addition, and linking farmers to markets. Among the essential knowledge base is reliable information about water utilisation by NUCS with potential for commercialisation. This commentary identifies and characterises NUCS with agronomic potential in SSA, especially in the semi-arid areas taking into consideration inter alia: (i) what can grow under water-scarce conditions, (ii) water requirements, and (iii) water productivity. Several representative leafy vegetables, tuber crops, cereal crops and grain legumes were identified as fitting the NUCS category. Agro-biodiversity remains essential for sustainable agriculture.

The future of water resources systems analysis: Toward a scientific framework for sustainable water management

Abstract: This paper presents a short history of water resources systems analysis from its beginnings in the Harvard Water Program, through its continuing evolution toward a general field of water resources systems science. Current systems analysis practice is widespread and addresses the most challenging water issues of our times, including water scarcity and drought, climate change, providing water for food and energy production, decision making amid competing objectives, and bringing economic incentives to bear on water use. The emergence of public recognition and concern for the state of water resources provides an opportune moment for the field to reorient to meet the complex, interdependent, interdisciplinary, and global nature of today's water challenges. At present, water resources systems analysis is limited by low scientific and academic visibility relative to its influence in practice and bridled by localized findings that are difficult to generalize. The evident success of water resource systems analysis in practice (which is set out in this paper) needs in future to be strengthened by substantiating the field as the science of water resources that seeks to predict the water resources variables and outcomes that are important to governments, industries, and the public the world over. Doing so promotes the scientific credibility of the field, provides understanding of the state of water resources and furnishes the basis for predicting the impacts of our water choices.

Reusing wastewater to cope with water scarcity: Economic, social and environmental considerations for decision-making

Abstract: Wastewater reuse has been recognized as an encouraging solution to cope with the problem of water scarcity around the globe. Adopting Integrated Water Resources Management principles will ensure that the implementation of wastewater reuse projects will take into account all the various types of affected stakeholders, accounting in addition for the external costs and benefits derived from the reuse decision. The objective of this paper is to analyze the economic, social and environmental aspects surrounding the concept of wastewater reuse in order to assist policy-makers and managers on the implementation of economic instruments for decision-making. This study proposes a methodological framework for conducting cost-benefit analysis, which is later exemplified by the Yarqon Recycling Project case study in Israel. In this case study application, 3 different scenarios (“pessimistic”, “base-case” and “optimistic”) with a range of parameters values, were used to estimate the most relevant internal and external costs and benefits. Additionally, the most influential parameters were identified using a sensitivity analysis that included both Monte Carlo simulations and the standardized regression coefficients method. For the “base-case” scenario, the net present value obtained was approximately $4.83 million. Although the feasibility of the project is demonstrated, the sensitivity analysis results were less favorable (likelihood of obtaining a positive result was only 64.28%), being the external recreational costs derived from irrigating with reclaimed wastewater the most influential parameter. The results of this analysis led to the conclusion that including the relevant externalities might have a strong impact on the economic feasibility of the wastewater reuse projects. The proposed methodological framework aims to guide decision-makers in evaluating their success with respect to Integrated Water Resources Management in economic terms.

Climate Change and Water Scarcity: The Case of Saudi Arabia

Abstract: Background Climate change is expected to bring increases in average global temperatures (1.4°C–5.8°C [34.52°F–42.44°F] by 2100) and precipitation levels to varying degrees around the globe. The availability and quality of water will be severely affected, and public health threats from the lack of this valuable resource will be great unless water-scarce nations are able to adapt. Saudi Arabia provides a good example of how the climate and unsustainable human activity go hand in hand in creating stress on and depleting water resources, and an example for adaptation and mitigation. Method A search of the English literature addressing climate change, water scarcity, human health, and related topics was conducted using online resources and databases accessed through the University at Albany, State University of New York library web page. Results Water scarcity, which encompasses both water availability and water quality, is an important indicator of health. Beyond drinking, water supply is intimately linked to food security, sanitation, and hygiene, which are primary contributors to the global burden of disease. Poor and disadvantaged populations are the ones who will suffer most from the negative effects of climate change on water supply and associated human health issues. Examples of adaptation and mitigation measures that can help reduce the strain on conventional water resources (surface waters and fossil aquifers or groundwater) include desalination, wastewater recycling and reuse, and outsourcing food items or “virtual water trade.” These are strategies being used by Saudi Arabia, a country that is water poor primarily due to decades of irresponsible irrigation practices. The human and environmental health risks associated with these adaptation measures are examined. Finally, strategies to protect human health through international collaboration and the importance of these efforts are discussed. Conclusion International, multidisciplinary cooperation and collaboration will be needed to promote global water security and to protect human health, particularly in low-income countries that do not have the resources necessary to adapt on their own.

Solar desalination: A sustainable solution to water crisis in Iran

Abstract: Water has a significant role in all our daily activities and its overall consumption is growing every day because of increasing scheme of mankind living standards. Iran is located in the dry belt of the earth, where nearly 70% of its area is located in arid and semi-arid regions. At the present time, Iran is experiencing a serious water crisis. It has been projected that the total per capita annual renewable water of the country will reach to about 800 m 3 by 2021, which is less than the global threshold of 1000 m 3 . In this context, seawater desalination seems to be a potential solution to meet the water supply and demand balance in Iran as the country is surrounded by three main water bodies of the Caspian Sea at northern and Persian Gulf and Sea of Oman at the southern borders. Annually, about 120 million cubic meter of freshwater supply is from conventional desalination plants centralized in the southern coastal regions of Iran. The fossil-fuel powered desalination systems are no longer sustainable to overcome the water crisis in the country due to both depletion risks of available energy resources and increase of greenhouse gas emissions. This is while that Iran has excellent solar energy potentials of about 15.3 kWh/m 2 /day, which can effectively be harnessed to run desalination processes. Therefore, in the modern time, solar desalination is an emerging solution to close the water gap in the country by considering the required change in terms of policy, financing, and regional cooperation to make this alternative method of desalination a success.

On inclusion of water resource management in Earth system models – Part 1: Problem definition and representation of water demand

Abstract: Human activities have caused various changes to the Earth system, and hence the interconnections between human activities and the Earth system should be recognized and reflected in models that simulate Earth system processes. One key anthropogenic activity is water resource management, which determines the dynamics of human–water interactions in time and space and controls human livelihoods and economy, including energy and food production. There are immediate needs to include water resource management in Earth system models. First, the extent of human water requirements is increasing rapidly at the global scale and it is crucial to analyze the possible imbalance between water demands and supply under various scenarios of climate change and across various temporal and spatial scales. Second, recent observations show that human–water interactions, manifested through water resource management, can substantially alter the terrestrial water cycle, affect land–atmospheric feedbacks and may further interact with climate and contribute to sea-level change. Due to the importance of water resource management in determining the future of the global water and climate cycles, the World Climate Research Program's Global Energy and Water Exchanges project (WRCP-GEWEX) has recently identified gaps in describing human–water interactions as one of the grand challenges in Earth system modeling (GEWEX, 2012). Here, we divide water resource management into two interdependent elements, related firstly to water demand and secondly to water supply and allocation. In this paper, we survey the current literature on how various components of water demand have been included in large-scale models, in particular land surface and global hydrological models. Issues of water supply and allocation are addressed in a companion paper. The available algorithms to represent the dominant demands are classified based on the demand type, mode of simulation and underlying modeling assumptions. We discuss the pros and cons of available algorithms, address various sources of uncertainty and highlight limitations in current applications. We conclude that current capability of large-scale models to represent human water demands is rather limited, particularly with respect to future projections and coupled land–atmospheric simulations. To fill these gaps, the available models, algorithms and data for representing various water demands should be systematically tested, intercompared and improved. In particular, human water demands should be considered in conjunction with water supply and allocation, particularly in the face of water scarcity and unknown future climate.

Freshwater ecosystem services supporting humans: Pivoting from water crisis to water solutions

Abstract: A new global scale water indicator, the freshwater provisioning index for humans (FPIh), maps the capacity of upstream source areas to provide water for human populations downstream. The freshwater provisioning index for humans combined with estimates of threats to water source areas assesses the compounded impacts on freshwater provisions at their point-of-service and the humans they support downstream. Nearly the entire world is serviced by freshwater sources compromised to a moderate extent through human activities, with 82% of the world’s population served by upstream areas exposed to high levels of threat. Globally, 75% of the world’s population benefits from engineered remediation of highly impaired source areas. Despite these gains, more than 80% of the global population still experiences moderate levels of threat impacting their freshwater provisions. Industrialized nations greatly limit their exposure to threats via infrastructure investments whereas regions in the developing world with moderate threat and little means of mitigation are viewed as the most vulnerable. Populations served by water source areas in industrialized countries receive highest threat reductions overall (50–70%) while those served by provision areas in the least developed countries receive <20% threat decrease. Better management of upstream source areas in poorer countries represents an opportunity to reduce threat lessening reliance on costly engineering solutions. Viewing the world in terms of the threats imposed on freshwater provisions combined with regional capacity to abate these impairments through infrastructure investments yields a spatial typology of freshwater resource development states reflecting region-specific challenges with unique management implications. Global mapping of threat development states provides a synoptic-scale diagnosis of key water resource challenges we link with state-specific water service management strategies including service area conservation, threat reduction, and green and gray infrastructure investments to more sustainably manage upstream freshwater provisions. This study provides a functional architecture to assess potential investment strategies to sustainably protect and manage critical upstream freshwater provisions addressing unique challenges faced by different regions of the world.

Water resources and their management in central Asia in the early twenty first century: status, challenges and future prospects

Abstract: Large parts of Central Asia are characterized by a semiarid to arid climate. Therefore, areas close to shallow groundwater, rivers and lakes are characterized by unique water-dependent ecosystems and human societies which have developed over millennia in close interaction with the naturally limited water resources. In the early 21st century, global climate change, population growth, river damming, large-scale water abstractions and rising levels of pollution exert multiple pressures on the region’s water resources, aquatic and terrestrial ecosystems at historically high levels. Water scarcity threatens the livelihood of populations locally and in transboundary settings by a growing competition over a limited resource. This context is of particular importance since all major rivers of the region cross at least one international border. The complexity and character of water-related challenges in the region mean that management approaches need to be integrative, taking into account the natural resource basis, environmental limits and the socio-cultural and geopolitical dimension. This paper frames the thematic issue of Environmental Earth Sciences and provides a comprehensive overview about the current state of knowledge about water resources and their management in Central Asia. There is a focus on case studies looking at the Selenga–Baikal–Angara Basin, the Lake Aral Basin including the Syr Darya and Amu Darya river systems, the Tarim and the Illi River Basins. Aiming to be an up-to-date interdisciplinary scientific reference on the region’s water-related challenges, this thematic issue gives theoretical and practical insights into solutions and best practice examples of water management.

Water Scarcity and Birth Outcomes in the Brazilian Semiarid

Abstract: Roughly one-third of the rural population in developing countries lives in arid and semiarid regions, facing recurrent water scarcity. This is likely to become an even more common situation with climate change. This paper analyzes the impact of rainfall fluctuations during the gestational period on health at birth in the Brazilian semiarid, highlighting the role of water scarcity as a determinant of early life health. We find that negative rainfall shocks are robustly correlated with higher infant mortality, lower birth weight, and shorter gestation periods. Mortality effects are concentrated on intestinal infections and malnutrition, and are greatly minimized when the local public health infrastructure is sufficiently developed (municipality coverage of piped water and sanitation). We also find that effects are stronger during the fetal period (2nd trimester of gestation), for children born during the dry season, and for mortality immediately after birth. Our estimates suggest that expansions in public health infrastructure would be a cost-effective way of reducing the response of infant mortality to rainfall scarcity.

Balancing water scarcity and quality for sustainable irrigated agriculture

Abstract: The challenge of meeting the projected doubling of global demand for food by 2050 is monumental. It is further exacerbated by the limited prospects for land expansion and rapidly dwindling water resources. A promising strategy for increasing crop yields per unit land requires the expansion of irrigated agriculture and the harnessing of water sources previously considered “marginal” (saline, treated effluent, and desalinated water). Such an expansion, however, must carefully consider potential long-term risks on soil hydroecological functioning. The study provides critical analyses of use of marginal water and management approaches to map out potential risks. Long-term application of treated effluent (TE) for irrigation has shown adverse impacts on soil transport properties, and introduces certain health risks due to the persistent exposure of soil biota to anthropogenic compounds (e.g., promoting antibiotic resistance). The availability of desalinated water (DS) for irrigation expands management options and improves yields while reducing irrigation amounts and salt loading into the soil. Quantitative models are used to delineate trends associated with long-term use of TE and DS considering agricultural, hydrological, and environmental aspects. The primary challenges to the sustainability of agroecosystems lies with the hazards of saline and sodic conditions, and the unintended consequences on soil hydroecological functioning. Multidisciplinary approaches that combine new scientific knowhow with legislative, economic, and societal tools are required to ensure safe and sustainable use of water resources of different qualities. The new scientific knowhow should provide quantitative models for integrating key biophysical processes with ecological interactions at appropriate spatial and temporal scales.

Changing mechanism of global water scarcity events: Impacts of socioeconomic changes and inter-annual hydro-climatic variability

Abstract: A B S T R A C T Changes in available fresh water resources, together with changes in water use, force our society to adapt continuously to water scarcity conditions. Although several studies assess the role of long-term climate change and socioeconomic developments on global water scarcity, the impact of inter-annual climate variability is less understood and often neglected. This paper presents a global scale water scarcity assessment that accounts for both temporal changes in socioeconomic conditions and hydro-climatic variability over the period 1960–2000. We thereby visualized for the first time possible over- and underestimations that may have been made in previous water scarcity assessments due to the use longterm means in their analyses. Subsequently, we quantified the relative contribution of hydro-climatic variability and socioeconomic developments on changing water scarcity conditions. We found that hydro-climatic variability and socioeconomic changes interact and that they can strengthen or attenuate each other, both regionally and at the global scale. In general, hydro-climatic variability can be held responsible for the largest share (>79%) of the yearly changes in global water scarcity, whilst only after six to ten years, socioeconomic developments become the largest driver of change. Moreover, our results showed that the growth in the relative contribution of socioeconomic developments to changing water scarcity conditions stabilizes towards 2000 and that the impacts of hydro-climatic variability remain significantly important. The findings presented in this paper could be of use for water managers and policy makers coping with water scarcity issues since correct information both on the current situation and regarding the relative contribution of different mechanisms shaping future conditions is key to successful adaptation and risk reduction.

Securing Water, Sustaining Growth: Report of the GWP/OECD Task Force on Water Security and Sustainable Growth

Abstract: The Global Dialogue for Water Security and Economic Growth is a joint initiative of the GWP and the OECD to promote and accelerate a transition to water security, by connecting policymakers and practitioners through global and country level consultations and through an expert task force analysis of the links between water security and sustainable economic growth. About GWP The mission of the Global Water Partnership (GWP) is to advance governance and management of water resources for sustainable and equitable development. GWP is an intergovernmental organisation and a global network of 13 Regional Water Partnerships, 85 Country Water Partnerships and more than 3,000 Partner organisations in 172 countries. The GWP network is committed to building a water secure world. About OECD The mission of the Organisation for Economic Cooperation and Development (OECD) is to promote policies that will improve the economic and social well-being of people around the world. The OECD provides a forum in which governments can work together to share experiences and seek solutions to common problems. We work with governments to understand what drives economic, social and environmental change. OECD work on water focuses on water economics and governance. It aims at facilitating the reform of water policies, so that they are better attuned to current and future challenges. The views expressed in this report do not necessarily represent the official views of the GWP, nor of the OECD and the governments of its constituent countries. Acknowledgements 8 Executive Summary 12 Chapter 1: Introduction 32 Chapter 2: Water security, sustainable growth, and well-being 36 2.1 The water security challenge 38 Framing the water security challenge 39 The importance of water endowments 41 2.2 The complex economics of water 44 The economic dynamics of water-related investments 44 Appraising investments in water security 46 Finding the right water security investments 47 2.3 A theoretical model of the dynamics of water-related risk, investment, and growth 50 2.4 An empirical analysis of the impact of hydrological variability on growth 54 The impact of hydro-climatic variability on economic growth 54 Two characteristics that influence vulnerability to water-related risks 62 2.5 Summary 64 Chapter 3: The global status of water security 68 3.1 Four headline risks 71 3.2 Risk-based indicators of water security 72 3.3 Global analysis of water security: (1) water scarcity 74 Likelihood of water scarcity 74 Consequence of surface and groundwater water scarcity 79 Projecting future agricultural risks and opportunities 83 …

Review and classification of indicators of green water availability and scarcity

Abstract: Research on water scarcity has mainly focussed on blue water (ground- and surface water), but green water (soil moisture returning to the atmosphere through evaporation) is also scarce, because its availability is limited and there are competing demands for green water. Crop production, grazing lands, forestry and terrestrial ecosystems are all sustained by green water. The implicit distribution or explicit allocation of limited green water resources over competitive demands determines which economic and environmental goods and services will be produced and may affect food security and nature conservation. We need to better understand green water scarcity to be able to measure, model, predict and handle it. This paper reviews and classifies around 80 indicators of green water availability and scarcity, and discusses the way forward to develop operational green water scarcity indicators that can broaden the scope of water scarcity assessments.

Smart water meter system for user-centric consumption measurement

Abstract: Water scarcity and water stress issues pose a serious threat to the global population. The traditional way of manual meter reading is furthermore inconvenient and time consuming, and it wastes resources. This method is also unable to manage the sustainable water resources effectively since it requires efficient, accurate and reliable monitoring techniques that enable the utilities sector and consumers to know the level of water consumption in real-time. Real-time smart water meters that can be monitored by the user are essential and constitute a key component of the water management system. A smart watermonitoring system will make users mindful of their water consumption and help them to reduce their water usage. At the same time, users will be alerted to abnormal water usage to reduce water loss. This paper introduces the water management system based on wireless sensor networks (WSN). The system uses the IEEE 802.15.4 standard embedded in ContikiOS LibCoAP as an open-source application to create a robust and intelligent system. Visualisation and monitoring of the system is achieved following the development of a web-based system and through Pandora FMS.

China's rising hydropower demand challenges water sector

Abstract: Demand for hydropower is increasing, yet the water footprints (WFs) of reservoirs and hydropower, and their contributions to water scarcity, are poorly understood. Here, we calculate reservoir WFs (freshwater that evaporates from reservoirs) and hydropower WFs (the WF of hydroelectricity) in China based on data from 875 representative reservoirs (209 with power plants). In 2010, the reservoir WF totaled 27.9 × 109 m3 (Gm3), or 22% of China’s total water consumption. Ignoring the reservoir WF seriously underestimates human water appropriation. The reservoir WF associated with industrial, domestic and agricultural WFs caused water scarcity in 6 of the 10 major Chinese river basins from 2 to 12 months annually. The hydropower WF was 6.6 Gm3 yr−1 or 3.6 m3 of water to produce a GJ (109 J) of electricity. Hydropower is a water intensive energy carrier. As a response to global climate change, the Chinese government has promoted a further increase in hydropower energy by 70% by 2020 compared to 2012. This energy policy imposes pressure on available freshwater resources and increases water scarcity. The water-energy nexus requires strategic and coordinated implementations of hydropower development among geographical regions, as well as trade-off analysis between rising energy demand and water use sustainability.

Is Desalination Affordable?—Regional Cost and Price Analysis

Abstract: Desalination has proven to be a reliable and efficient water supply option in many countries, especially in times of water scarcity. However, high desalination costs and high prices for desalinated water (twice or three times higher than those from traditional water sources) have been hindering an uptake and the development of desalination in many countries. Applied desalination technology, capital and operational costs, production capacity, water salinity are just a few factors determining the final cost of desalinated water that varies considerably between $1.7–9.5/kgal ($0.45–2.51/m3). The final prices for desalinated water and the related costs for local municipalities are among the most crucial determinants of the overall short- and long-term effectiveness of desalination processes. This paper provides an in-depth analysis on economics of desalination with country specific examples. It depicts a comprehensive picture of cost variability of desalinated water and points out challenges for cost-effective desalination in the future.

Water Footprint of Cities: A Review and Suggestions for Future Research

Abstract: Cities are hotspots of commodity consumption, with implications for both local and systemic water resources. Water flows “virtually” into and out of cities through the extensive cross-boundary exchange of goods and services. Both virtual and real water flows are affected by water supply investments and urban planning decisions, which influence residential, commercial, and industrial development. This form of water “teleconnection” is being increasingly recognized as an important aspect of water decision-making. The role of trade and virtual water flows as an alternative to expanding a city’s “real” water supply is rarely acknowledged, with an emphasis placed instead on monotonic expansion of engineering potable water supplies. We perform a literature review of water footprint studies to evaluate the potential and importance of taking virtual flows into account in urban planning and policy. We compare and contrast current methods to assess virtual water flows. We also identify and discuss priorities for future research in urban water footprint analysis.