Top PDF Water supply reservoir operation in the framework of climate variability and change

Water supply reservoir operation in the framework of climate variability and change

Water supply reservoir operation in the framework of climate variability and change

Recent local studies also suggest that due to climate change there is a likelihood of a uniform annual increase in temperature and caused the regional precipitation patterns vary considerably (Zakaria and Shaaban, 2007; Shaaban et al., 2011) for most of the watersheds of the country. Regarding the annual rainfall, the east coast region is expected to experience 10% increase while the west coast and southern areas may drop by 5% (Zakaria and Shaaban, 2007). Similarly, the projected increase of annual surface temperature in between 1.0°C to 1.5°C for a future period of 25 years (Salmah and Liew, 2008; Tangang et al., 2007) over all regions may have directly influenced the potential evapotranspiration and subsequently the quantity of the runoff component. Consequently, the availability of water resources in the region would be affected whereby in the past, many operational decisions depend explicitly on the assumptions about future climatic conditions. A few studies have been carried out to incorporate the variation of climate change factor in reservoir planning and operation (Eum and Simonovic, 2010; Karamouz et al., 2012). Therefore there is a need to develop an integrated approach to consider these factors on climate change impact on streamflow and derive adaptive policies for possible optimal reservoir operation.
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Adapting or maladapting? Climate change, climate variability, disasters and resettlement in Malawi

Adapting or maladapting? Climate change, climate variability, disasters and resettlement in Malawi

When people who occupy places that are exposed to floods are provided with the option of relocating to safer places, many opt to remain in high-risk areas than move, or return after relocating. This paper applies a theoretical framework grounded in social- psychological and socio-economic factors to understand why some households resettle while others stay. Applying the protection motivation theory, the study finds that those that feel that resettlement will only protect them from floods but not drought or other hazards are less likely to resettle. Although socio-economic factors are found to be weaker predictors of resettlement outcomes compared to socio-psychological ones, the study shows that those with high income are less likely to resettle and thus remain ‘trapped’ in risky areas. These findings demonstrate some of the challenges that vulnerable households in low-income countries face as they adapt to climate change, within the context of equally demanding livelihood needs. The study, conducted through a mixed methods design in rural Malawi, also demonstrates the need to pay more attention to social-psychological factors when designing and implementing adaptation and disaster risk reduction policies. By demonstrating that both those moving and those who stay are mostly coping or maladapting rather than adapting, the findings challenge the commonly promoted short-term mechanical fixes. Rather, they point to the need for policy options that are more encompassing and promote sustainable adaptation and disaster risk reduction.
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A modelling framework to project future climate change impacts on streamflow variability and extremes in the West River, China

A modelling framework to project future climate change impacts on streamflow variability and extremes in the West River, China

Many studies indicate that the risk of both floods and droughts is very likely to rise in many parts of the world under a warmer climate with increased climate variability (IPCC 2007). To effectively manage our water resources and adapt to climate change induced natural hazards, investigation of the global warming effects on future hydro-climate extreme events, the possible changes in future streamflow variability and extremes is essential. Such investigation is usually achieved by performing macro-scale hydrological modelling, driven by climate scenario datasets from either general circulation models (GCMs) or regional climate models (RCMs).
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Streamflow Forecast and Reservoir Operation Performance Assessment Under Climate Change

Streamflow Forecast and Reservoir Operation Performance Assessment Under Climate Change

Decisions regarding reservoir operations are especially important for seasonally balanced water supplies and the protection of reservoir downstream from drought or flooding in the North American prairie where snow accumulation and snowmelt act as an important water source for streamflow generation. Global warming may bring a more uncertain change in air temperature and precipitation which seriously influence the hydrological processes and water supply. In order to investigate the potential impact of climate change on the hydrological processes and water resources in the region, this study applies system dynamics as an effective methodology to organize and integrate existing information available on climate change scenarios, watershed hydrologic processes, reservoir operation and water resource assessment system. As a result, demand is assumed to remain constant for the next 100 years. The global climate model CGCM2 is applied to generate the climate change scenarios showing a clear picture of climate change in a large scale with daily climate change data series for hydrologic modeling. Watershed-based hydrologic and water volume dynamics modeling focus on the dynamics process of both streamflow formation within the wa- tershed driven by climatic parameters, and the reservoir water volume change under reservoir operation rules. The selected hydrologic model explains the interactions among the surface and subsurface storage, and reflects the phenomena of dynamic change in vegetation canopy and soil physical state as active temperature changes in the winter as well as the contribution of snowpack accumulation and snowmelt to streamflow. The reservoir water volume dynamics modeling follows the reservoir operation rules which are based on the demands from the different stakeholders. The reliability measure describes the effectiveness of present reservoir operation rules to meet the demands on drought protection, water security and flood control. The results indicate that fast global population growth with rather slow economic and technological development may accelerate an increase in the temperature in the prairie region, which may bring more high-peak-streamflow occurrences and more water resources in terms of annual total streamflow in the region. Reliability assessment demonstrates that current reservoir operation rules can provide a high reliability in drought protection and flood control for the reservoir downstream under two selected climate change scenarios. More water resources from climate variation and change imply a shifting of current high priority of reservoir operating rules from drought protection to water secure aspects. Different stakeholder may benefit more from this priority adjustment.
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Assessing the Impacts of Climate Change on Streamflow and Reservoir Operation in Central Florida

Assessing the Impacts of Climate Change on Streamflow and Reservoir Operation in Central Florida

Climate change is a global concern but how will this impact water supply? This is a major question that water managers are trying to answer using General Circulation Models (GCMs). A GCM is a numerical model that simulates how oceans, atmosphere, land surface and cryosphere will respond to increasing greenhouse gas concentrations. There are multiple GCMs and runs, each taking into account different forcing scenarios. These scenarios include varied amounts of greenhouse gas emissions by certain time periods, changes in temperature, population growth and more. GCMs are created at a coarse resolution, around 250 and 600 kilometers (km) to simulate the entire earth. To support the spatial resolution of regional hydrologic simulations required for water supply, hydrologists have developed dynamical and statistical techniques to downscale a GCM to a regional scale (~1 to 10 km) (Ahmed et al. 2012, Daniels et al. 2012, and Sharma et al. 2013); however, these techniques cause biases such as variances in mean precipitation, underestimation of high precipitation, or differences in number of drizzle days (Grillakis et al. 2013; IPCC 2013). It is unknown if these techniques alter precipitation signals embedded in these models or if they reproduce climate states that are viable for water resource planning and management. Replicating important historical climate states such as wet or dry season or El Niño Southern Oscillation (ENSO) is vital for water supply; therefore it is critical to understand GCM shortcomings prior to implementation for future projection scenarios.
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Comparative study on the reservoir operation planning

with the climate change adaptation

Comparative study on the reservoir operation planning with the climate change adaptation

Figure  11 reveals the proposed monthly water release and WL for Analysis 1 and Analysis 2 using NSGA-II for time period of 2040–2069. The monthly optimum res- ervoir storage was designed between 200 MCM/month (69 m) and 1050 MCM/month (97 m). Considering all the objectives, the water balance can be achieved. The water storage of Pedu reservoir was predicted to achieve its optimal water level using both analyses. The reservoir needs to sustain its capability to supply water espe- cially in early cultivation period. However, Fig.  11 shows Analysis 1 proposed higher WL and water demand for every month than Analysis 2 except in March. During these years, zero water transfer from Muda reservoir and more water spillover were recorded prove by the incre- ment of water inflow and decrement of water demand at study area due to the climate simulation in the future. In the future year, the proportion of irrigation demand for Muda Irrigation Scheme was estimated to change
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Long-Term Evaluation of Norris Reservoir Operation Under Climate Change

Long-Term Evaluation of Norris Reservoir Operation Under Climate Change

As hydro-climatic databases have expanded and confidence in climate models have increased, professional climatology researchers have consistently concluded that climate change will impact to water resource infrastructure (Frederick and Major 1997, IPCC 2013). Furthermore, the Intergovernmental Panel on Climate Change’s (IPCC) Fifth Assessment Report (AR5) states that the period from 1983-2012 has likely been the warmest 30-year period in the past 1400 years, and that there has been a linear trend of the globally averaged combined land and ocean temperature increasing 0.85 °C since 1880 (IPCC 2013). Studies have also shown that climate change has increased the probability of occurrence for extreme climatic events (Allen and Ingram 2002, Bell et al. 2004, Gao et al. 2012, WMO 2013, IPCC 2013). The southeastern United States has experienced increases in moderate to extreme summer droughts since the 1970’s and annual average autumn precipitation since 1901 by 14 and 30 percent, respectively (Karl et al. 2009). Due to these increases, major infrastructure concerns regarding water supply and reservoir proficiency (flood and reservoir failure prevention, hydroelectric generation, transportation, etc.) have become apparent (Christensen et al. 2004, Payne et al. 2004, Helton et al. 2006, Choi 2011).
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Reservoir Operation Under Different Climate Change Scenarios

Reservoir Operation Under Different Climate Change Scenarios

Abstract— As a result of tropical monsoon climate with strongly variable flow in time and space, India has lot of reservoirs, which play a significant role in the development of the country economy. Most of the reservoir is multipurpose including flood control. Hydropower generation, water supply, navigation, restoration, etc. Design of hydrological systems has traditionally been carried out on the assumption that the available flow records for a location reflect stationary climatic conditions. In view of the ongoing climate change the assumption of stationarity of climatic data is not justified. Operational decisions for water resources infrastructure such as reservoirs are dependent on both the timings and magnitude of flows, and therefore climate change impact assessment must consider both these characteristics. In this paper, optimal storage trajectories have been determined for Bhakra reservoir in Satluj River Basin for four different inflow sequences reflecting diverse set of climatic conditions using dynamic programming. The objective of operation was to maximize revenues from power generation subject to constraints on storages and releases from the reservoir. The intent was to create an ensemble of reservoir operating rules that would correspond to diverse climatic conditions, and therefore assist reservoirs managers in decision making. The results of analysis of derived storage trajectories clearly indicate that the climate change has potentially important implications for the operation of Bhakra reservoir. Analysis presented herein is likely to lend credibility to recent climate change modelling efforts for a reservoir fed by Himalayan rivers that are anticipated to experience potentially serious impacts of climate change. A distinct practical advantage of the simulation model presented here is that it can be used to simulate the operation of reservoirs under various user defined operating policies.
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Evaluating the variability in surface water reservoir planning characteristics during climate change impacts assessment

Evaluating the variability in surface water reservoir planning characteristics during climate change impacts assessment

quick juxtaposition of both figures will reveal that R t < R v as expected, which is why caution should be exercised when adopting the time-based reliability for system evaluation: the fact that time-based reliability is low does not make the water supply situ- ation of the system poor. Thus, as noted by Adeloye (2012) , while the initial evaluation of systems performance can be based on the time based reliability R t because it is simple to estimate and might be readily recognised by users who are already familiar with the concept of return periods, the volumetric reliability should also be evaluated and any necessary adjustments made to system’s characteristics in the light of this. For example, the R t may be relaxed (or reduced), such as through increasing the release from the reservoir to meet additional needs or adopting a lower reser- voir capacity during planning, if the R v is very high. From Fig. 11 b, it is evident that, R t is improving when the rainfall is increasing as expected; similarly temperature increases also improved the R t , due to additional runoff availability from snow and glacier melt from the Himalayas. Contrary to R t , the R v shows less variability for all the scenarios.
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Climate change and climate variability: personal motivation for adaptation and mitigation

Climate change and climate variability: personal motivation for adaptation and mitigation

reactive responses to current climate impacts not cov- ered in our survey. They could be supported with tax incentives and technical solutions and government agen- cies should work with communities to address their needs. From the other predictors only gender was asso- ciated with either autonomous adaptation action, with women appearing to be less adaptive. The majority of study participants had adapted to extreme weather con- ditions by cooling off in air conditioned places, reducing physical exertion or using a fan. These autonomous adaptation actions are reactive in nature, more so than proactive and thus does not capture anticipatory (proac- tive or planned) adaptive intentions. The survey instru- ment was initially designed to capture anticipatory adaptation as well by asking respondents if they adapted their home to climate change. For example: have you installed an A/C, insulation, insect screens, eliminated mosquitoes breeding sites, etc. However, due to low fre- quency responses these questions were eliminated from the analysis; thus the results apply to autonomous adap- tation only and not to long-term impacts. Other studies that did not specifically examine the psychological con- structs of the HBM have shown that adaptive behaviour to climate change may be more strongly linked to fac- tors such as, environmental attitudes, political affiliation and attitudes towards scientists [39-41]. The relative dif- ferences in predictors of our mitigation and adaptation outcomes might in part be due to the wording of the survey questions. Nevertheless, health as a communica- tion frame can be used to complement other strategies to augment the public response [42].
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Adaptation to Climate Change and Variability in eastern Ethiopia

Adaptation to Climate Change and Variability in eastern Ethiopia

The parameter estimates of the MNL model provide only the direction of the effect of the independent variables on the dependent variable shown in Table 1. Thus, the marginal effects measure the expected change in probability of a particular choice being made with respect to unit change in an explanatory variable (Green, 2012; Long, 1997). The signs of the marginal effects and respective coefficients may be different, as the former depend on the sign and magnitude of all other coefficients. Then, the interpretations for each of the adaptive strategy are has reduced farm productivity and household food security. Although farmers have been able to deal with past related hazards is forcing farmers to engage more frequently in emergency coping strategies such as consuming seeds reserved for planting and
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Engaging Supply Chains in Climate Change

Engaging Supply Chains in Climate Change

to develop and maintain a GHG reporting system. Firms engaging in these efforts also bear the opportunity cost of the required capital and personnel time. Suppliers weigh these investments against the potential impact on their competitive position, such as whether they will be better positioned to win or retain contracts, whether these tasks can help develop a capability that can differentiate the firm from its competitors, and whether responding will help them avoid penalties that might arise from failing to comply with a buyer’s request. While some of the costs are relatively easy to quantify, the newness of this context and the rapidly changing public and political views regarding climate change render other costs and benefits highly uncertain. For example, since there is no established benchmark for an acceptable level of suppliers’ GHG emissions, a supplier might not know whether the information it shares will be viewed by its buyers as acceptable or unacceptable and whether sharing information might bring new business or penalties. The uncertainty about carbon costs that might be imposed by GHG emissions regulations and the uncertainty about consumer preference for less carbon-intensive products and services make it impossible for suppliers to know what—if any—strategic benefits they will achieve by sharing climate change information with their buyers.
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Reservoir operating rules for urban water supply systems

Reservoir operating rules for urban water supply systems

The general opinion of reviews by Yakowitz (1982) and Yeh (1985) on systems analysis applications of water resources systems is that dynamic programming (DP) can be successfully used [r]

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Climate Change and Water Transfers

Climate Change and Water Transfers

Real Choices: The Case for Market Valuation of Water, 38 TEX. The report cites to the example of Colorado, where "[dlespite additional available water supplies in the [r]

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Water constraints on European power supply under climate change: Impacts on electricity prices

Water constraints on European power supply under climate change: Impacts on electricity prices

Based on projected changes in thermoelectric and hydropower generating capacity under climate change, we calculated changes in wholesale electricity prices, production and electricity producer surplus. We used scenarios of future installed power plant capacities, electricity exchange capacities, cost figures and electricity demand based on the European Network of Transmission System Operators for Electricity (ENTSO-E 2010, 2011, 2012). Our calculations are based on the assumption that at each point in time electricity supply has to meet electricity demand. In addition, we assumed that existing power plants are used in order of their short-term marginal cost 6 . Country specific electricity supply curves were identified taking the cost for electricity imports into account. The wholesale price corresponds to the price where electricity supply meets demand, and the price at the wholesale market equals the production cost of the most expensive power plant in operation. We assumed a price elasticity of 0 for the demand for electricity, because changes in spot market prices have overall small impacts on end-user prices and demands. Equations (1a)–(1c) show the optimization approach (objective function) of our model. Equation (1b) reflects that electricity supply has to meet electricity demand, whereas electricity can be supplied either by using domestic power plants or by importing electricity from a foreign country. Equation (1c) describes the grid capacities, which could be used to export electricity from country n to country m.
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Energy Supply and Climate Change in Nigeria

Energy Supply and Climate Change in Nigeria

To what extent will changing climate being experienced all across the globe in various dimension impact the energy industry? What coping strategies or mechanism are available in addressing this critical menace that has been regarded as one of the greatest threat to humanity in the 21 st century? These are issues on top agenda for policy makers all around the world. Energy is very vital in driving the growth and development of any economy as it is an essential input to a nation ’s growth and development (Akinbami, 2009) and also strategic to increasing the competitiveness of any economy (Adenikinju, 2008). The energy sector plays a key and central role in the growth and development of any nation, therefore, the reliable and adequate supply of energy is essential to support economic activities and industrialization efforts that will enhance income and standard of living. This is evident in the fact that any form of shock in the sector automatically reverberates into other sectors of the economy as all the sectors require energy for power. The use of energy is, therefore, a prerequisite for virtually all economic activity, and it is crucial to be able to access sufficient amounts of energy at acceptable cost (both from an economic and environmental perspective), which gives r ise to the notion of ‘energy security’ (Greenleaf et al, 2009).
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Climate change and water supply in the Mekong Delta and Ho Chi Minh City

Climate change and water supply in the Mekong Delta and Ho Chi Minh City

Many of the 100 m deep wells show a significant increase in salinity over time; some of the 400 m deep wells also, although the salinity in others seems stable (Table 1). The water produced at WTP 2 at Phu Loi does not meet the Vietnamese standard for clean water of 250 mg/l with respect to chloride (Cl - ), nor the 300 mg/l as per special dispensation. The water company of Soc Trang province intends to use the water that will be produced by the Perfector-R surface water treatment plant to dilute the water produced at Phu Loi. Eventually water production at this well field may have to be stopped altogether.
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Water Resource Management & Climate Variability

Water Resource Management & Climate Variability

There are more than 11.8 million people living on the border today; estimates place the 2020 population at 19.4 million. Ninety percent of this population is concentrated in 14 interdependent “twin cities” that span the boundary. The rapid growth experienced in the cities on the Mexican side of the border has resulted in numerous challenges, including unplanned development, increased demand for land, energy, and water resources, greater traffic congestion, increased production of waste that strains already-inadequate waste treatment facilities, and other pressures

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Water Distribution Solution for More Efficient Operation of Water Supply

Water Distribution Solution for More Efficient Operation of Water Supply

worked by splitting the above network up into five large district metered areas (DMAs) and then further dividing each of these into three virtual areas, giving a total of 15 virtual areas for the purposes of leak management. The two existing methods involve using and not using DMAs respectively. The former method splits the network into 15 DMAs for leak management and the latter method manages the entire network as a single undivided area. The management cost in Fig. 9 consists of the sum of all costs associated with leak management, including capital investment for things like establishing the DMAs and installing sensors, leak survey costs, and the cost of water lost due to leaks. The results show that the management cost for the new technique is approximately 10% lower than the existing method using DMAs. This was because the new technique requires less capital investment for splitting the network into DMAs.
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Climate Change and Climate Variability for Mysore Taluk using RS and GIS

Climate Change and Climate Variability for Mysore Taluk using RS and GIS

find the climate change on in relation to climatic parameters for Mysore taluk. To analyze the variations in climatic parameters like Rainfall data, temperature data were used. NDVI analysis, MODIS TERRA data was used. Whereas, NCEP reanalysis, Relative Humidity, Soil Moisture, Solar radiation, water runoff were used. The findings of the study shows that the climate variability and climate change for Mysore Taluk from 1986 to 2016, the monthly rainfall is increase in trend and monsoon rainfall shows decrease in trend. And the monthly, summer, monsoon minimum temperature shows that decrease in trend. The monthly maximum temperature shows decrease in trend but in case of summer and monsoon seasons increase in trend respectively.
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