Potential Impact of Climate Change on Residential Energy Consumption in Dhaka City

This study aimed to assess the impacts of climate change on residential energy consumption in Dhaka city of Bangladesh. The monthly electricity consumption data for the period 2011–2014 and long-term climate variables namely monthly rainfall and temperature records (1961–2010) were used in the study. An ensemble of six global circulation models (GCMs) of coupled model intercomparison project phase 5 (CMIP5) namely, BCCCSM1-1, CanESM2, MIROC5, MIROC-ESM, MIROC-ESM-CHEM, and NorESM1-M under four representative concentration pathway (RCP) scenarios were used to project future changes in rainfall and temperature. The regression models describing the relationship between historical energy consumption and climate variables were developed to project future changes in energy consumptions. The results revealed that daily energy consumption in Dhaka city increases in the range of 6.46–11.97 and 2.37–6.25 MkWh at 95% level of confidence for every increase of temperature by 1 °C and daily average rainfall by 1 mm, respectively. This study concluded that daily total residential energy demand and peak demand in Dhaka city can increase up to 5.9–15.6 and 5.1–16.7%, respectively, by the end of this century under different climate change scenarios.     

Evaluating climatic and non-climatic stresses for declining surface water quality in Bagmati River of Nepal

Both climatic and non-climatic factors affect surface water quality. Similar to its effect across various sectors and areas, climate change has potential to affect surface water quality directly and indirectly. On the one hand, the rise in temperature enhances the microbial activity and decomposition of organic matter in the river system and changes in rainfall alter discharge and water flow in the river ultimately affecting pollution dilution level. On the other hand, the disposal of organic waste and channelizing municipal sewage into the rivers seriously worsen water quality. This study attempts to relate hydro-climatology, water quality, and impact of climatic and non-climatic stresses in affecting river water quality in the upper Bagmati basin in Central Nepal. The results showed that the key water quality indicators such as dissolved oxygen and chemical oxygen demand are getting worse in recent years. No significant relationships were found between the key water quality indicators and changes in key climatic variables. However, the water quality indicators correlated with the increase in urban population and per capita waste production in the city. The findings of this study indicate that dealing with non-climatic stressors such as reducing direct disposal of sewerage and other wastes in the river rather than emphasizing on working with the effects from climate change would largely help to improve water quality in the river flowing from highly populated urban areas.     

Study of the Climate Change Impacts on Water Quality in the Upstream Portion of the Cau River Basin,Vietnam

This paper presents simulations of climate change impacts on water quality in the upstream portion of the Cau River Basin in the North of Vietnam. The integrated modeling system GIBSI was used to simulate hydrological processes, pollutant and sediment wash-off in the river basin, and pollutant transport and transformation in the river network. Three projections for climate change based on emission scenarios B1, B2, and A2 of IPCC Special Report on Emission Scenarios (SRES) were considered. By assuming that the input pollution sources and watershed configuration were constant, based on 2008 data, water quality in the river network was simulated up to the terminal year 2050. For each climate change scenario, patterns of precipitation in wet and dry year were considered. The change in annual and monthly trends for dissolved oxygen (DO), biochemical oxygen demand (BOD), and ammonium ions (NH4+) load and concentration for different portions of the watershed have been analyzed. The results of these simulations show that climate change has more impact on changing the seasonal water quality parameters than on altering the average annual load of the pollutants. The percent change and change pattern in water quality parameters are different for wet and dry year, and the changes in wet year are smaller than those in dry year.     

Variable-source flood pulsing in a semi-arid transboundary watershed: the Chobe River, Botswana and Namibia

The Chobe River, characterized by an unusual flood pulsing regime and shared between Botswana and Namibia, lies at the heart of the world’s largest transfrontier conservation area (the Kavango–Zambezi Transfrontier Conservation Area). Significant ecological changes and vegetation conversions are occurring along its floodplains. Various scenarios for agricultural and urban water use are currently being proposed by the government of Botswana. However, the understanding of the river’s annual flow regime and timing of the relative contributions of water from three different sources is relatively poor. In light of past and future climate change and variability, this means that allocating water between ecological flows and economic and domestic uses will become increasingly challenging. We reconstruct the inundation history in this basin to help ease this challenge. This paper presents a spatiotemporal approach to estimate the contribution of water from various sources and the magnitude of changes in the flooding extent in the basin between 1985 and 2010. We used time series analysis of bimonthly NOAA AVHRR and NASA MODIS data and climatologic and hydrologic records to determine the flooding timing and extent. The results indicate that between 12 and 62 % of the basin is flooded on an annual basis and that the spatial extent of the flooding varies throughout the year as a function of the timing of peak discharge in two larger basins. A 30-year trend analysis indicates a consistent decline in the average monthly flooded area in the basin. The results may prove useful in future water utilization feasibility studies, in determining measures for protecting ecological flows and levels, and in ecosystem dynamics studies in the context of current and future climate change and variability.     

Land Use and Climate Change Impacts on the Hydrology of the Bago River Basin,Myanmar

Assessment of land use and climate change impacts on the hydrological cycle is important for basin scale water resources management. This study aims to investigate the potential impacts of land use and climate change on the hydrology of the Bago River Basin in Myanmar. Two scenarios from the representative concentration pathways (RCPs): RCP4.5 and RCP8.5 recommended by the Intergovernmental Panel on Climate Change, Fifth Assessment Report (IPCC AR5) were used to project the future climate of 2020s, 2050s, and 2080s. Six general circulation models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) were selected to project the future climate in the basin. An increase of average temperature in the range of 0.7 to 1.5 °C and 0.9 to 2.7 °C was observed under RCP 4.5 and RCP 8.5, respectively, in future periods. Similarly, average annual precipitation shows a distinct increase in all three periods with the highest increase in 2050s. A well calibrated and validated Soil and Water Assessment Tool (SWAT) was used to simulate the land use and climate change impacts on future stream flows in the basin. It is observed that the impact of climate change on stream flow is higher than the land use change in the near future. The combined impacts of land use and climate change can increase the annual stream flow up to 68 % in the near future. The findings of this study would be beneficial to improve land and water management decisions and in formulating adaptation strategies to reduce the negative impacts, and harness the positive impacts of land use and climate change in the Bago River Basin.     

Hydrodynamic Simulation of River Yamuna for Riverbed Assessment: A Case Study of Delhi Region

A well known river hydrodynamic model RiverCAD has been used to simulate and visualize flood scenarios for different designated flood flows under complex riverbed geometry with several man made structures like bridges and barrages. The model applied successfully for the stretch of 23 km in the Yamuna floodplain of Delhi region from Wazirabad barrage in the upstream to Okhla barrage. Flood flows for various return periods namely once in 10, 25, 50 and 100 years were estimated based on recorded flow data for the period of 1963 to 2003 using standard flood frequency analysis techniques. The simulation results were compared and the model was calibrated with water surface elevation records of the previous floods at various barrage and bridge locations. Simulation results enabled prediction of maximum water levels, submergence scenarios and land availability under different designated flood flows for riverbed assessment, development and management.     

Estimation of environmental flow incorporating water quality and hypothetical climate change scenarios

Environmental flows (Eflow, hereafter) are the flows to be maintained in the river for its healthy functioning and the sustenance and protection of aquatic ecosystems. Estimation of Eflow in any river stretch demands consideration of various factors such as flow regime, ecosystem, and health of river. However, most of the Eflow estimation studies have neglected the water quality factor. This study urges the need to consider water quality criterion in the estimation of Eflow and proposes a framework for estimating Eflow incorporating water quality variations under present and hypothetical future scenarios of climate change and pollution load. The proposed framework is applied on the polluted stretch of Yamuna River passing through Delhi, India. Required Eflow at various locations along the stretch are determined by considering possible variations in future water quantity and quality. Eflow values satisfying minimum quality requirements for different river water usage classes (classes A, B, C, and D as specified by the Central Pollution Control Board, India) are found to be between 700 and 800 m³/s. The estimated Eflow values may aid policymakers to derive upstream storage-release policies or effluent restrictions. Generalized nature of this framework will help its implementation on any river systems.     

Adaptation to Climatic Variability and Change: Asian Perspectives on Agriculture and Food Security

The impacts of climate change on potential rice production in Asia are reviewed in the light of the adaptation to climatic variability and change. Collaborative studies carried out by IRRI and US-EPA reported that using process-based crop simulation models increasing temperature may decrease rice potential yield up to 7.4% per degree increment of temperature. When climate scenarios predicted by GCMs were applied it was demonstrated that rice production in Asia may decline by 3.8% under the climates of the next century. Moreover, changes in rainfall pattern and distribution were also found suggesting the possible shift of agricultural lands in the region. The studies however have not taken the impacts of climatic variability into account, which often produce extreme events like that caused by monsoons and El Niño. Shifts in rice-growing areas are likely to be constrained by land-use changes occurring for other developmental reasons, which may force greater cultivation of marginal lands and further deforestation. This should be taken into account and lead to more integrated assessment, especially in developing countries where land-use change is more a top-down policy rather than farmers' decision. A key question is: To what extent will improving the ability of societies to cope with current climatic variability through changing design of agricultural systems and practices help the same societies cope with the likely changes in climate?     

Hydrology of mountainous areas in the upper Indus Basin, Northern Pakistan with the perspective of climate change

Mountainous areas in the northern Pakistan are blessed by numerous rivers that have great potential in water resources and hydropower production. Many of these rivers are unexploited for their water resource potential. If the potential of these rivers are explored, hydropower production and water supplies in these areas may be improved. The Indus is the main river originating from mountainous area of the Himalayas of Baltistan, Pakistan in which most of the smaller streams drain. In this paper, the hydrology of the mountainous areas in northern Pakistan is studied to estimate flow pattern, long-term trend in river flows, characteristics of the watersheds, and variability in flow and water resource due to impact of climate change. Eight watersheds including Gilgit, Hunza, Shigar, Shyok, Astore, Jhelum, Swat, and Chitral, Pakistan have been studied from 1960 to 2005 to monitor hydrological changes in relation to variability in precipitation, temperature and mean monthly flows, trend of snow melt runoff, analysis of daily hydrographs, water yield and runoff relationship, and flow duration curves. Precipitation from ten meteorological stations in mountainous area of northern Pakistan showed variability in the winter and summer rains and did not indicate a uniform distribution of rains. Review of mean monthly temperature of ten stations suggested that the Upper Indus Basin can be categorized into three hydrological regimes, i.e., high-altitude catchments with large glacierized parts, middle-altitude catchments south of Karakoram, and foothill catchments. Analysis of daily runoff data (1960-2005) of eight watersheds indicated nearly a uniform pattern with much of the runoff in summer (June-August). Impact of climate change on long-term recorded annual runoff of eight watersheds showed fair water flows at the Hunza and Jhelum Rivers while rest of the rivers indicated increased trends in runoff volumes. The study of the water yield availability indicated a minimum trend in Shyok River at Yogo and a maximum trend in Swat River at Kalam. Long-term recorded data used to estimate flow duration curves have shown a uniform trend and are important for hydropower generation for Pakistan which is seriously facing power crisis in last 5 years.     

Assessing different sources of uncertainty in hydrological projections of high and low flows: case study for Omerli Basin,Istanbul, Turkey

This study investigates the assessment of uncertainty contribution in projected changes of high and low flows from parameterization of a hydrological model and inputs of ensemble regional climate models (RCM). An ensemble of climate projections including 15 global circulation model (GCM)/RCM combinations and two bias corrections (change factor (CF) and bias correction in mean (BC)) was used to generate streamflow series for a reference and future period using the Hydrologiska Byråns Vattenbalansavdelning (HBV) model with the 25 best-fit parameter sets based on four objective functions. The occurrence time of high flows is also assessed through seasonality index calculation. Results indicated that the inputs of hydrological model from ensemble climate models accounts for greater contribution to the uncertainty related to projected changes in high flows comparing to the contribution from hydrological model parameterization. However, the uncertainty contribution is opposite for low flows, particularly for CF method. Both CF and BC increases the total mean variance of high and low flows. The variability in the occurrence time of high flows through RCMs is greater than the variability resulted from hydrological model parameters with and without statistical downscaling. The CF provides more accurate timing than BC and it shows the most pronounced changes in flood seasonality.     

Evaluating climate change effects on water and salt resources in Salt Lake, Turkey using multitemporal SPOT imagery

The main goal of this study is to investigate the dimension of climate change effects in Salt Lake and its vicinity in Turkey using satellite remote sensing data. The first stage of the study includes evaluation of the multitemporal climatic data on the Salt Lake Basin Area, Turkey for a period of 35 years (1970–2005). The changes in mean temperature and precipitation are evaluated for the study area by comparing two periods, 1970–1992 and 1993–2005. In the second stage, the effects of climate changes in the Salt Lake are investigated by evaluating water and salt reserve changes through seasonal and multitemporal SPOT imagery collected in 1987 and 2005. The climatic data and remotely sensed and treated satellite images show that water and salt reserve in Salt Lake has decreased between 1987 and 2005 due to drought and uncontrolled water usage. It is suggested that the use of water supplies, especially underground waters, around the Salt Lake should be controlled and the lake should regularly be monitored by current remote sensing data for an effective management of water and salt resources in the region.     

Impacts of water resources development on flow regimes in the Brazos River

The Brazos River, the second largest basin in Texas, represents one of the most highly developed river systems in the state. Thirty-nine reservoirs with capacities greater than 5,000 acre-feet are currently in operation in the basin. Impacts on stream ecosystems are evidenced by changes in flow regimes and resulting changes in fish assemblages over the past 50 years. These changes have been widely attributed to human impacts, through the construction of dams, diversion of water supplies for agricultural and municipal uses, and land use change. However, streamflow regimes result from a complex mix of drivers that include climate, topography, land cover, land use practices, reservoir management practices, dam releases, and water consumption patterns, making determination of anthropogenic impacts problematic. This study quantifies changes in flow regime and probable historical drivers including precipitation, dam construction, population growth, and changing water demand in the Brazos River basin over the past 100 years. Results indicate that the climate of the basin has been relatively stable over the study period, while large-scale changes in human population densities and intense water resources development are correlated with impacts on flow regimes, decreasing the frequency and magnitude of high flow events and stabilizing low flows. These changes have resulted in an increase of habitat generalist fish species, a decrease of native obligate riverine fishes, and an overall homogenization of species assemblages. The results of this study indicate the importance of combining ecological data with an assessment of social drivers for a greater understanding of the dynamics of river basin systems.     

Water quality in Lis river, Portugal

In the past 30?years, the Lis river basin has been subjected to constant ecological disasters mainly due to piggery untreated wastewater discharges. The aim of this study was to evaluate the effect of existing domestic, agricultural, and industrial activities on the water quality, and to propose a watershed plan to protect and manage surface water resources within the Lis river basin. For this purpose, 16 monitoring stations have been strategically selected along the Lis river stretch and its main tributaries to evaluate the water quality in six different sampling periods (2003–2006). All samples were characterized in terms of organic material, nutrients, chlorophyll, and pathogenic bacteria. Generally, the Lis river presents poor water quality, according to environmental quality standards for surface water, principally in terms of dissolved oxygen, biochemical oxygen demand, total nitrogen, and fecal coliform, which can be associated mainly with the contamination source from pig-breeding farms.     

Modeling Wetland Plant Community Response to Assess Water-Level Regulation Scenarios in the Lake Ontario – St. Lawrence River Basin

The International Joint Commission has recently completed a five-year study (2000–2005) to review the operation of structures controlling the flows and levels of the Lake Ontario – St. Lawrence River system. In addition to addressing the multitude of stakeholder interests, the regulation plan review also considers environmental sustainability and integrity of wetlands and various ecosystem components. The present paper outlines the general approach, scientific methodology and applied management considerations of studies quantifying the relationships between hydrology and wetland plant assemblages (% occurrence, surface area) in Lake Ontario and the Upper and Lower St. Lawrence River. Although similar study designs were used across the study region, different methodologies were required that were specifically adapted to suit the important regional differences between the lake and river systems, range in water-level variations, and confounding factors (geomorphic types, exposure, sediment characteristics, downstream gradient of water quality, origin of water masses in the Lower River). Performance indicators (metrics), such as total area of wetland in meadow marsh vegetation type, that link wetland response to water levels will be used to assess the effects of different regulation plans under current and future (climate change) water-supply scenarios.The Canadian Crown reserves the right to retain a non-exclusive, royalty free licence in and to any copyright.     

Statistical Modeling of Health Effects on Climate-Sensitive Variables and Assessment of Environmental Burden of Diseases Attributable to Climate Change in Nepal

An ecological time-series study is conducted to quantify health-effect coefficients associated with climate-sensitive variables namely temperature, rainfall, relative humidity, and wind speed and estimate environmental burden of diseases attributed to temperature as the main climatic variable together with climate change in Nepal. The study is based upon daily data of climate-sensitive variables and hospitalizations collected for 5 years between 2009 and 2014. Generalized linear model is used to estimate health-effect coefficients accounting distributed lag effects. Results show 3.08%, 10.14%, and 3.27% rise in water-borne, vector-borne, and renal disease hospitalizations, respectively, and 3.67% rise in water- and vector-borne disease deaths per 1 °C rise in average temperature. Similarly, 2.45% and 1.44% rise in heart disease hospitalization and all-cause mortality, respectively per 1 °C rise in absolute difference of average temperature with its overall average (20 °C). The computed attributable fractions are 0.3759, 0.6696, 0.2909, and 0.1024 for water-borne, vector-borne, renal, and heart disease hospitalizations, respectively, and 0.0607 and 0.4335 for all-cause mortality and disease-specific mortality of water- and vector-borne diseases, respectively. The percent change in attributable burdens due to climate change are found to be 4.32%, 4.64%, 7.20%, and ?2.29% for water-borne, vector-borne, renal, and heart disease hospitalizations, respectively, and ?1.39% and 6.55% for all-cause deaths and water-borne and vector-borne disease deaths, respectively. In conclusion, climate-sensitive variables have significant effects on many major health burdens in Nepal. In the context of changing climatic scenarios around the world including that of Nepal, such changes are bound to affect the health burden of Nepalese people.     

Constructing “not Implausible” Climate and Economic Scenarios for Egypt

A space of “not-implausible” scenarios for Egypt's future under climate change is defined along two dimensions. One depicts representative climate change and climate variability scenarios that span the realm of possibility. Some would not be very threatening. Others portend dramatic reductions in average flows into Lake Nassar and associated increases in the likelihood of year to year shortfalls below critical coping thresholds; these would be extremely troublesome, especially if they were cast in the context of increased political instability across the entire Nile Basin. Still others depict futures along which relatively routine and relatively inexpensive adaptation might be anticipated. The ability to adapt to change and to cope with more severe extremes would, however, be linked inexorably to the second set of social–political–economic scenarios. The second dimension, defined as “anthropogenic” social/economic/political scenarios describe the holistic environment within which the determinants of adaptive capacity for water management, agriculture, and coastal zone management must be assessed. This revised version was published online in July 2006 with corrections to the Cover Date.     

Regional impact analysis of climate change on natural and managed forests in the Federal State of Brandenburg, Germany

A methodology for regional application of forest simulation models has been developed as part of an assessment of possible climate change impacts in the Federal state of Brandenburg (Germany). Here we report on the application of a forest gap model to analyse the impacts of climate change on species composition and productivity of natural and managed forests in Brandenburg using a statistical method for the development of climate scenarios. The forest model was linked to a GIS that includes soil and groundwater table maps, as well as gridded climate data with a resolution of 10 × 10 km and simulated a steady-state species composition which was classified into forest types based on the biomass distribution between species. Different climate scenarios were used to assess the sensitivity of species composition to climate change. The simulated forest distribution patterns for current climate were compared with a map of Potential Natural Vegetation (PNV) of Brandenburg.In order to analyse the possible consequences of climate change on forest management, we used forest inventory data to initialize the model with representative forest stands. Simulation experiments with two different management strategies indicated how forest management could respond to the projected impacts of climate change. The combination of regional analysis of natural forest dynamics under climate change with simulation experiments for managed forests outlines possible trends for the forest resources. The implications of the results are discussed, emphasizing the regional differences in environmental risks and the adaptation potentials of forestry in Brandenburg.     

downscaling procedures as a tool for integration of multiple air issues

In assessing the risks associated with climate change,downscaling has proven useful in linking surfacechanges, at scales relevant to decision making, tolarge-scale atmospheric circulation derived from GCMoutput. Stochastic downscaling is related to synopticclimatology, weather-typing approaches (classifyingcirculation patterns) such as the Lamb Weather Typesdeveloped for the United Kingdom (UK), the EuropeanGrosswetterlagen (Bardossy and Plate, 1992) and thePerfect Prognosis (Perfect Prog) method from numericalweather prediction. The large-scale atmosphericcirculation is linked with site-specific observationsof atmospheric variables, such as precipitation, windspeed or temperature, within a specified region. Classifying each day by circulation patterns isachieved by clustering algorithms, fuzzy rule bases,neural nets or decision trees. The linkages areextended to GCM output to account for climate change. Stochastic models are developed from the probabilitydistributions for extreme events. Objective analysiscan be used to interpolate values of these models toother locations. The concepts and some applicationsare reviewed to provide a basis for extending thedownscaling approach to assessing the integrated riskof the six air issues: climate change, UV-B radiation,acid rain, transport of hazardous air pollutants, smogand suspended particulates.     

Simulations of groundwater-surface water interaction and particle movement due to the effect of weir construction in the sub-watershed of the river Labe in the town of Děčín

Steady- and transient-state simulations of groundwater flow and particle movement in the sub-watershed of the river Labe in Dě?ín town was carried out using Visual MODFLOW software. The simulations were performed for calibration and for the scenarios that the change in the water level of the river Labe was undergoing. Steady-state simulation was carried out for the sake of calibration of model outputs. For transient simulation, two different scenarios were considered in order to investigate the response of the aquifer system to the stresses applied on surface water of the river. The simulation results have shown that the surface water and groundwater interactions, and the subsequent particle movement were affected by the stresses applied on the surface water in the river Labe. The first scenario involved the rapid recharge of surface water to the aquifer in the vicinity of the river while particles still move towards the river at the places far away from the river. At the end of the second scenario, particles still tend to move towards the river slowly and finally tend to stay within the aquifer as equilibrium of hydraulic gradient is reached between the surface and groundwater levels. The time series graphs of hydraulic heads at all observation wells show that the groundwater level in the surrounding aquifer rises significantly as a result of recharges from the river. The local water balance of the study area was calculated and expressed as the rates of water entering and leaving the system. At the end of the second scenario, the difference between the rate of flow into and out of the model area was 0.73 m³ day^?1.     

Biophysical and socioeconomic characterization of a water-stressed area and simulating agri-production estimates and land use planning under normal and extreme climatic events: a case study

This study aims in linking the biophysical and socioeconomic data base layers with the technical coefficients or simulation models for agri-production estimates and land use planning under normal and extreme climatic events, and exploring the resource and inputs management options in village Shikohpur, Gurgaon district located in the northwest part of India. The socioeconomic profile of Shikohpur is highly skewed with mostly small and marginal farmers. Though the areas under wheat in Shikohpur are increasing, the productivity is declining or remaining stagnant over the years. Most of the area during kharif season (June-September) remains fallow. Pearl millet based cropping systems (pearl millet-mustard and pearl millet-wheat) are predominant. Soils are mostly loamy sand to sandy loam with average of 70-80% sand content. Organic C content in soil is less than 0.3%, due to high prevailing temperature with little rainfall and also intensive agriculture followed in this region. Though the annual average seasonal rainfall in Gurgaon did not have much variation over the years, occurrence of extreme climate events has increased in the last two decades. The crop intensity is low and the water table is declining. Water and nitrogen production functions were developed for the important crops of the region, for their subsequent use in scheduling of the inputs. InfoCrop, WTGROWS and technical coefficients were used for crop planning and resource management under climate change and its variability, extreme events, limited resource availability and crop intensification. These will help in disseminating necessary agro-advisories to the farmers so that they will be able to manipulate the inputs and agronomic management practices for sustained agricultural production under normal as well as extreme climatic conditions.