Impacts of climate change on lakes and reservoirs dynamics and restoration policies

Meteorological-driven processes exert large and diverse impacts on lakes and their water quality; these impacts can be hydrologic, thermal, hydraulic, chemical, biochemical, or ecological. The impact of climate change on Lake Tahoe (California–Nevada) was investigated here as a case study of climate change effects on the physical processes occurring within lakes. The already published trends of meteorological variables were used to assess the effects of global warming on Lake Tahoe dynamics. Records from the period 1969–2002 show that Lake Tahoe has became warmer and more stable. A series of simulation years into the future (i.e., 2000–2040) was established using flows, loads, and meteorology data sets for the period 1994–2004. Results of 40-year simulations show that the lake continues to become warmer and more stable, and mixing is reduced. Possible changes in water quality because of global warming are discussed through inference, although these are not specifically simulated. Many existing problems may be exacerbated due to climate change, yet extreme uncertainty depends on the rate and magnitude of climate change. Therefore, shifts in water quality and quantity due to climate change should be integrated into contemporary planning and management in an adaptive manner, and the research and development of impact assessment methodology should focus on approaches that can handle extreme uncertainty. The general alternatives for lake management due to climate change are discussed. Depending on the specific case, further intensive research is suggested to restore lake water quality.     

Climate Change Impacts and Adaptation Strategies in Kenya

Abstract

To determine the climate changes that are due to natural variability and those due to human activities is quite challenging, just like delineating the impacts. Moreover, it is equally difficult to ascertain the adaptive strategies for coping with the climate changes and in particular for developing countries like Kenya. While climate change is a global phenomenon, the impacts are more or less specific to local areas such as observed in Kenyan case. Therefore climate change impacts adaptation strategies are appropriately applicable to a given local perspective. The study investigated the main indicators of climate change and effective adaptive strategies that can be employed in Kenya. Based on online questionnaire survey, the study established unpredictable rainfall patterns as the major indicator of climate change in the country, while water harvesting and change of cropping methods are the best adaptive strategies.     

Climate adaptation of interconnected infrastructures: a framework for supporting governance

Infrastructures are critical for human society, but vulnerable to climate change. The current body of research on infrastructure adaptation does not adequately account for the interconnectedness of infrastructures, both internally and with one another. We take a step toward addressing this gap through the introduction of a framework for infrastructure adaptation that conceptualizes infrastructures as complex socio-technical “systems of systems” embedded in a changing natural environment. We demonstrate the use of this framework by structuring potential climate change impacts and identifying adaptation options for a preliminary set of cases—road, electricity and drinking water infrastructures. By helping to clarify the relationships between impacts at different levels, we find that the framework facilitates the identification of key nodes in the web of possible impacts and helps in the identification of particularly nocuous weather conditions. We also explore how the framework may be applied more comprehensively to facilitate adaptation governance. We suggest that it may help to ensure that the mental models of stakeholders and the quantitative models of researchers incorporate the essential aspects of interacting climate and infrastructure systems. Further research is necessary to test the framework in these contexts and to determine when and where its application may be most beneficial.     

Climate change impacts on irrigation water requirements in the Guadalquivir river basin in Spain

Irrigated production in the Guadalquivir river basin in Spain has grown significantly over the last decade. As a consequence, water resources are under severe pressure, with an increasing deficit between available supplies and water demand. To conserve supplies, the water authority has reduced the volume of water assigned to each irrigation district. Major infrastructural investments have also been made to improve irrigation efficiency, including the adoption of high technology micro-irrigation systems. Within a context of increasing water scarcity, climate change threatens to exacerbate the current supply-demand imbalance. In this study, the impacts of climate change on irrigation water demand have been modelled and mapped. Using a combination of crop and geographic information systems, maps showing the predicted spatial impacts of changes in agroclimate (climate variables that determine the irrigation requirements) and irrigation need have been produced. The maps highlight a significant predicted increase in aridity and irrigation need. Modelling of irrigation water requirements shows a typical increase of between 15 and 20% in seasonal irrigation need by the 2050s, depending on location and cropping pattern, coupled with changes in seasonal timing of demand.     

Application of the City Blueprint Approach to assess the challenges of water management and governance in Quito (Ecuador)

In this paper, we provide an assessment of the challenges of water, waste and climate change in the city of Quito by performing the City Blueprint Approach consisting of three assessment frameworks: (1) the Trends and Pressure Framework (TPF), (2) the City Blueprint Framework (CBF) and (3) the water Governance Capacity Framework (GCF). The TPF summarizes the main social, environmental and financial aspects that may affect urban water management. The CBF provides a clear overview of sustainable urban water management performance and its bottlenecks in municipalities and regions. The GCF comprises nine governance conditions which each consist of three indicators. The GCF provides insight in the most effective improvements to increase the governance capacity to address the identified urban water challenges. Our results show that poor wastewater treatment and long-term drinking water security are Quito’s main water challenges that may be jeopardized given the city’s rapid urbanization and economic pressure. The GCF analysis reveals that cooperation between stakeholders, implementing capacity and citizens’ awareness are the most important conditions for further development to find adequate solutions for Quito’s long-term drinking water security. We also suggest that more attention should be drawn to the transparency, accountability and participation principles. The results of Quito show that the City Blueprint Approach can serve as an affordable quick-scan to facilitate cities in their strategic planning to reach their sustainable development goals.     

Economic water management decisions: trade-offs between conflicting objectives in the sub-middle region of the São Francisco watershed

Hydro-economic models can measure the economic effects of different reservoir operating rules, environmental restrictions, maintenance of ecosystems, technical constraints, institutional constraints, land use change, and climate change. To determine the optimal economic water allocation, for its main uses in the sub-middle of the São Francisco River Basin, a hydro-economic optimization model was developed and applied. Demand curves were used rather than fixed requirements for water resources. The results show that operation rules of reservoirs and institutional constraints, such as priorities for human consumption, have high impacts on costs and benefits of the principal economic uses in the study area. Especially, costs of environmental demands, like minimum ecological river flow, have high impacts on the water resource management. Scarcity costs of irrigation users associated with maintaining ecosystems and environmental constraints are particularly significant. The results from this study provide a better understanding of the water trade-offs for future policymaking and efficient water management. Policymaking for the water resources should consider the food-water-energy-environment nexus at a regional scale to minimize environmental and economic cost under water scarcity and land use change.     

Assessment of regional climate change impacts on Hungarian landscapes

The assessment of regional climate change impacts combined with the sensitivity of landscape functions by predictive modelling of hazardous landscape processes is a new fundamental field of research. In particular, this study investigates the effects of changing weather extremes on meso-regional-scale landscape vulnerability. Climatic-exposure parameter analysis was performed on a predicted climate change scenario. The exposure to climate change was analysed on the basis of the original data of the meso-scale IPCC A1B climate scenario from the REMO and ALADIN regional models for the periods of 2021–2050 and 2071–2100, and the regional types of climate change impacts were calculated by using cluster analysis. Selected climate exposure parameters of the REMO and ALADIN models were analysed, in particular, for extreme events (days with precipitation greater than 30 mm, heat waves, dry periods, wet periods) and for daily temperature and precipitation. The landscape functions impacted by climate change are proxies for the main recent and future problematic processes in Hungary. Soil erosion caused by water, drought, soil erosion caused by wind, mass movement and flash floods were analysed for the time periods of 1961–1990, 2021–2050 and 2071–2100. Based on the sensitivity thresholds for the impact assessments, the landscape functional sensitivity indicators were interpreted, and an integrative summary of the five indicators was made, differentiating the regions facing only a few or multiple sensitivities. In Central Hungary, the increasing exposure and sensitivity to droughts will be a serious problem when following the REMO scenario. In several regions, most indicators will change the sensitivity threshold from a tolerable risk to an increased or very high risk.     

A commentary on recent water safety initiatives in the context of water utility risk management

Over the last decade, suppliers of drinking water have recognised the limitations of relying solely on end-product monitoring to ensure safe water quality and have sought to reinforce their approach by adopting preventative strategies where risks are proactively identified, assessed and managed. This is leading to the development of water safety plans; structured 'route maps' for managing risks to water supply, from catchment to consumer taps. This paper reviews the Hazard Analysis and Critical Control Point (HACCP) procedure on which many water safety plans are based and considers its appropriateness in the context of drinking water risk management. We examine water safety plans in a broad context, looking at a variety of monitoring, optimisation and risk management initiatives that can be taken to improve drinking water safety. These are cross-compared using a simple framework that facilitates an integrated approach to water safety. Finally, we look at how risk management practices are being integrated across water companies and how this is likely to affect the future development of water safety plans.     

Risk as a challenge in practice: investigating climate change in water management

Climate change is one of the risks that society faces today. Among other things, it has the potential to interfere with the water environment, and thus it can be a relevant factor in current work with river basin management plans (RBMPs) in Denmark. At the same time, climate change in theory has characteristics that can pose challenges, if included in such a planning process. In this article, it is investigated what the attitudes towards climate change are among actors in the planning process, and what the main drivers, barriers and challenges related to including climate change in the RBMPs are, compared to the theoretical challenges. The investigation consists of a document study of hearing responses, interviews, and a survey among Danish municipalities. The overall results are that there are many attitudes towards the inclusion of climate change as a factor in RBMPs and that this diversity theoretically can be a challenge in the planning process. The main theoretical and practical barriers and challenges in connection with inclusion of climate change in RBMPs relate to lacking knowledge and uncertainty.     

Water pollution in Pakistan and its impact on public health--a review

Water pollution is one of the major threats to public health in Pakistan. Drinking water quality is poorly managed and monitored. Pakistan ranks at number 80 among 122 nations regarding drinking water quality. Drinking water sources, both surface and groundwater are contaminated with coliforms, toxic metals and pesticides throughout the country. Various drinking water quality parameters set by WHO are frequently violated. Human activities like improper disposal of municipal and industrial effluents and indiscriminate applications of agrochemicals in agriculture are the main factors contributing to the deterioration of water quality. Microbial and chemical pollutants are the main factors responsible exclusively or in combination for various public health problems. This review discusses a detailed layout of drinking water quality in Pakistan with special emphasis on major pollutants, sources of pollution and the consequent health problems. The data presented in this review are extracted from various studies published in national and international journals. Also reports released by the government and non-governmental organizations are included.     

An ecohydrological adaptive approach to a salt lake in the semiarid grasslands of Argentina: future management perspectives

Past extreme hydrological events, future climate change scenarios and approaches for lake management were studied in the Argentinean Pampa. Anthropogenic climate change will impact water bodies and create enormous challenges for water management. Adaptation strategies are needed urgently to deal with the uncertainties originated by climate change on inland or coastal basins. Only a few studies have addressed practical strategies to mitigate global change impacts on lakes and practically none in South America. The purpose of this work was to discuss management options and seek better adaptive alternatives for the nature reserve Lake Chasicó, and to propose future management experiments and actions at a regional level. The ecohydrological approach is likely to increase the ecological resilience of the lake, dampen climate-driven hydrological variations and reduce eutrophication problems. Future projects should include wetland creation, fish management, water quality control, engineering work studies and education programs. Ecohydrology as an integrative natural science should be considered as a water management strategy to build ecological resilience into water bodies. The building of social-ecological resilience is also crucial for the stability of coupled human-ecological systems. The integration of natural and social sciences into sustainability approaches represents a robust strategy for adapting to climate change.     

Sub-basin scale characterization of climate change vulnerability, impacts and adaptation in an Indian River basin

Knowledge of climate change vulnerability and impacts is a prerequisite for formulating locally relevant climate change adaptation policies. A participatory approach has been used in this study to determine climate change vulnerability, impacts and adaptation aspects for the Kangsabati River basin, India. The study approach involved engaging with stakeholders representing state (sub-national), district and community levels, through an interactive brainstorming method, to understand stakeholder perceptions regarding (a) local characteristics which influence vulnerability, (b) climate change impacts and (c) relevant adaptation options. The study reveals that vulnerability varies across upstream, midstream and downstream sections of the river basin. Suggested adaptation options, in this predominantly agricultural basin, are found to be applicable across spatial scales. Stakeholder perceptions, regarding vulnerability and impacts, vary with the level of interaction, academic background and type of experience. Interaction confirms the notion that stakeholders have inherent knowledge regarding adaptation, reveals their preferences and ability to think unconventionally. We discuss limitations of the approach while demonstrating its ability to deliver locally relevant and acceptable adaptation options, which could facilitate implementation. We conclude that engaging stakeholders at multiple levels was highly effective in assessing locally relevant aspects of climate change vulnerability, impacts and applicable adaptation options in the Kangsabati River basin. Based on this assessment, a sub-basin scale is recommended for evaluating these aspects, especially for water resources and agricultural systems, through multi-level stakeholder input.     

Policy entrepreneurs in international river basins—getting climate adaptation on the cross-border water policy agenda

In this study, we look at the role which water policy entrepreneurs play in promoting and stimulating climate adaptation measures in international river basins. In a Dutch-German case study in the Rhine delta, we explore the range of strategies that policy entrepreneurs employ in cross-border water management to effectively anchor and embed climate adaptation in the water policy debate.

We focus on climate adaptation on the local and regional scale in the Deltarhine region where increased flooding and prolonged drought periods are expected under the current climate change scenarios with a considerable impact on flood protection, agricultural activities, drinking water and ecosystem development.

We analyse the impact of policy entrepreneurs while coping with the challenging cross-border setting and dealing with structural differences in national systems such as the legal and institutional framework. It is shown that whilst the European water guidelines advocate a river basin approach across borders, the guidelines do not (yet) play a catalyst role regarding climate adaptation, and the presence and activities of policy entrepreneurs contribute in putting climate adaptation on the cross-border policy agenda.

Finally, marked differences in the presence of entrepreneurs in Germany and the Netherlands are observed for which two important complementary explanations are offered relating to contextual elements of power asymmetry and dependency as well as different policy styles and organisational cultures in both countries.

     

How do soil and water conservation practices influence climate change impacts on potato production? Evidence from eastern Canada

We used a stochastic production function method together with a farm-level dataset covering 18 farms over a 23-year period to assess the role that soil and water conservation practices play in affecting the climate change impacts on potato yield in northwestern New Brunswick, Canada. Our analysis accounted for the yield effects of farm inputs, farm technologies, farm-specific factors, seasonal climatic variables, soil and water conservation practices, and a series of interaction terms between soil and water conservation practices and climatic variables. Regression results were used in combination with three climate change scenarios developed by the Intergovernmental Panel on Climate Change (A2, A1B, B1) and four general circulation model predictions over three 30-year time periods (2011–2040, 2041–2070, and 2071–2100) to estimate a range of potato yield projections over these time periods. Results show that accounting for soil and water conservation practices in climate–yield relationships increased the impacts of climate change on potato yield, with yield increases of up to 38 % by the 2071–2100 period. These findings provide evidence that adoption of soil and water conservation practices can help boost potato production in a changing Canadian climate.     

Perceptions of climate change risks in primary resource use industries: a survey of the Canadian mining sector

A survey documenting how climate change is perceived, experienced, and responded to in the Canadian mining sector was administered to industry practitioners at the Prospectors & Developers Association of Canada annual meeting. Nine key findings from the survey are discussed: (1) The Canadian mining sector is sensitive to climate-related conditions. (2) Climate change is perceived to be having a negative impact on mining operations. (3) Companies are taking action to manage the current impacts. (4) Cost and uncertainty are commonly identified barriers to adapting to current climate change. (5) Future climate change is expected to have impacts for the industry. (6) Climate change projections are perceived as threats by the majority of respondents. (7) Despite the perceived threat, companies are not currently taking action to plan for future impacts. (8) Cost and uncertainty are commonly identified barriers to adapting to future climate change impacts. (9) The mining sector is currently making efforts to reduce greenhouse gas emissions. The survey is exploratory in nature, establishing a baseline for targeted research to assess in greater detail the vulnerability of mining to climate change.     

Climate change threats to environment in the tropical Andes: glaciers and water resources

Almost all of the world’s glaciers in the tropical latitudes are located in the Central Andes (Peru, Bolivia, Ecuador and Colombia). Due to their high altitude, to the high level of radiation and to the tropical climate dynamics, they all are particularly threatened by climate change, as a result of not only warming, but also of changing variability of precipitation. Many glaciers are of crucial importance for the livelihood of the local populations and even for three capitals, Lima (Peru), La Paz (Bolivia) and Quito (Ecuador), which depend on them for water and energy supplies. This paper shows that after a period of increased flow due to the glacier melt disequilibrium, the available water resource will decrease along with the rapid shrinking of the glaciers considered as water reservoirs. The case of the Cordillera Blanca (Peru) is analyzed more in detail with the mid-term (20 years) and long-term (1–2 centuries) impact of the glacier shrinking on the local water resources. Associated risks for the population and consequences for the human activities (tourism, hydropower, agriculture and stock-breeding, large-scale irrigation) are described at each stage of the mountain range.     

Dangerous levels of climate change for agricultural production in China

There are increasing attempts to define the measures of ‘dangerous anthropogenic inference with the climate system’ in context of Article 2 of the Framework Convention on Climate Change, due to its linkage to goals for stabilizing greenhouse gas concentrations. The criteria for identifying dangerous anthropogenic interference may be characterized in terms of the consequences of climate change. In this study, we use the water stress index (WSI) and agricultural net primary production (NPP) as indictors to assess where and when there might be dangerous effects arising from the projected climate changes for Chinese agricultural production. The results showed that based on HadCM3-based climate change scenarios, the region between the North China Plain and Northeast China Plain (34.25–47.75°N, 110.25–126.25°E) would be vulnerable to the projected climate change. The analyses on inter-annual variability showed that the agricultural water resources conditions would fluctuate through the period of 2001–2080 in the region under IPCC SRES A2 scenario, with the period of 2021–2040 as critical drought period. Agricultural NPP is projected to have a general increasing trend through the period of 2001–2080; however, it could decrease during the period of 2005–2035 in the region under the IPCC SRES A2 scenario, and during the period of 2025–2035 under IPCC SRES B2 scenario. Generally, while projected climate change could bring some potentially improved conditions for Chinese agriculture, it could also bring some critical adverse changes in water resources, which would affect the overall outcome. At this stage, while we have identified certain risks and established the general shape of the damage curve expressed as a function of global mean temperature increase, more works are needed to identify specific changes which could be dangerous for food security in China. Therefore, there is a need for the development of more integrated assessment models, which include social-economic, agricultural production and food trade modules, to help identify thresholds for impacts in further studies.     

Climate proofing the Zuidplaspolder: a guiding model approach to climate adaptation

Climate change will have an impact on various sectors, such as housing, infrastructure, recreation and agriculture. Climate change may change spatial demands. For example, rising temperatures will increase the need for recreation areas, and areas could be assigned for water storage. There is a growing sense that, especially at the local scale, spatial planning has a key role in addressing the causes and impacts of climate change. This paper promotes an approach to help translate information on climate change impacts into a guiding model for adaptive spatial planning. We describe how guiding models can be used in designing integrated adaptation strategies. The concept of guiding models has been developed in the 1990s by Tjallingii to translate the principles of integrated water management in urban planning. We have integrated information about the present and future climate change and set up a climate adaptation guiding model approach. Making use of climate adaptation guiding models, spatial planners should be able to better cope with complexities of climate change impacts and be able to translate these to implications for spatial planning. The climate adaptation guiding model approach was first applied in the Zuidplaspolder case study, one of the first major attempts in the Netherlands to develop and implement an integrated adaptation strategy. This paper demonstrates how the construction of climate adaptation guiding models requires a participatory approach and how the use of climate adaptation guiding models can contribute to the information needs of spatial planners at the local scale, leading to an increasing sense of urgency and integrated adaptation planning process.     

Risk to water security for small islands: an assessment framework and application

The freshwater resources of small islands are particularly vulnerable to the impacts of climate change and human stressors due to their limited extent and adaptive capacity. A water security approach is useful for effective management of the water resources; however, understanding risk to water security is critical in order to effectively plan and adapt to future changes. Currently available assessment tools generally do not incorporate risk and are not suitable for application on small islands, where the hydrogeological setting has unique vulnerabilities. The aim of this work is to provide a framework to characterize risk to water security for small islands. The risk assessment was developed using Andros Island, the Bahamas, as a case study area. Numerical modelling characterizes the response of the water system to potential future stressors related to climate change and human development, the results of which are integrated into the assessment framework. Based on risk assessment principles, indicators are determined for susceptibility, hazard threat, vulnerability and loss, in order to define the risk to water security. The resulting indicators are presented in geospatial maps that rank areas of risk to water security. These maps were provided to local water managers and policy-makers in the Bahamas as a tool to identify high-risk areas for near-term action and to inform long-term planning. The maps have also been used as a platform to engage local residents and raise awareness about the impact climate change and land-use activities may have on water security.     

Human health effects of residual carbon nanotubes and traditional water treatment chemicals in drinking water

The volume of industrial and domestic wastewater is increasing significantly year by year with the change in the lifestyle based on mass consumption and mass disposal brought about by the dramatic development of economies and industries. Therefore, effective advanced wastewater treatment is required because wastewater contains a variety of constituents such as particles, organic materials, and emulsion depending on the resource. However, residual chemicals that remain during the treatment of wastewaters form a variety of known and unknown by-products through reactions between the chemicals and some pollutants. Chronic exposure to these by-products or residual chemicals through the ingestion of drinking water, inhalation and dermal contact during regular indoor activities (e.g., showering, bathing, cooking) may pose cancer and non-cancer risks to human health. For example, residual aluminium salts in treated water may cause Alzheimer's disease (AD). As for carbon nanotubes (CNTs), despite their potential impacts on human health and the environment having been receiving more and more attention in the recent past, existing information on the toxicity of CNTs in drinking water is limited with many open questions. Furthermore, though general topics on the human health impacts of traditional water treatment chemicals have been studied, no comparative analysis has been done. Therefore, a qualitative comparison of the human health effects of both residual CNTs and traditional water treatment chemicals is given in this paper. In addition, it is also important to cover and compare the human health effects of CNTs to those of traditional water treatment chemicals together in one review because they are both used for water treatment and purification.