Climate Change and Water Resource Availability: An Impact Assessment for Bombay and Madras,India

ABSTRACT

Global climate change associated with rising atmospheric concentrations of greenhouse gases may alter regional temperature and precipitation patterns. Such changes could threaten the availability of water resources/Or rapidly growing Third World cities, many of which are already experiencing severe water supply deficiencies. This paper investigates the potential impacts of climate change on water resource availability for two Indian cities, Bombay and Madras. The paper begins by discussing future trends for population growth and water demand in each city. Nat, using climate change scenarios based on three general circulation models (GCMs), the paper assesses how climate change may affect water availability in the two urban regions. The assessment is conducted through the use of a monthly dryness index measuring potential evapotranspiration and precipitation. For each region, the dryness index under “normal” climatic conditions is compared with indexes created using GCM scenarios. The results of this assessment indicate that, unless large increases in regional precipitation accompany climate warming, higher rates of evapotranspiration will mean reduced water availability for both cities. The paper concludes by discussing some implications for water management in Third World cities.     

Using Large Climate Ensembles to Plan for the Hydrological Impact of Climate Change in the Freshwater Environment

We explore the use of large ensembles of climate scenarios to inform climate change adaptation in response to hydrological impacts on the freshwater environment, using a sensitive chalk river in south east England to illustrate the approach. The climateprediction.net experiment provides large ensembles of transient climate series from 1920 to 2080. We use 246 transient climate series in the CATCHMOD rainfall-run-off model to develop large ensembles of plausible river flows for the River Itchen. This transient ensemble allows the exploration of how flows may change through the twenty-first century, and demonstrates the range of possible consequences for freshwater ecosystems, based on invertebrate community impacts. Hydrological modelling of flow sequences including abstraction allows the continued effectiveness of river support from groundwater to be assessed. A new environmental impact matrix considers the response of the freshwater ecosystem in the Itchen, concentrating particularly on macro-invertebrates. Through the century increasing numbers of models fail the flow targets, with a minority of models suggesting flows that would lead to irreversible change to the invertebrate community. The large ensemble provides a richer picture of the range of possible change, allowing managers to explore a range of different responses. The approach used is illustrative, but demonstrates that large ensembles may be of great value in improving the understanding of the possible impact of climate change, provided that they can be communicated effectively to decision-makers.     

Water Resource Availability in Three Catchments of Swaziland under Expected Climate Change

Abstract

The greenhouse gases (CO₂, CH₄, N₂O, HFCs, PFCs, and SF₆) concentrations in the atmosphere have increased very much since the industrial revolution. The greenhouse gas effect has been projected to cause a global average temperature increase on the order of 1.4 to 5.8°C over the period of 1990 to 2100. The global average annual precipitation is projected to increase during the 21^st century due to the greenhouse effect. The impact of climate change on hydrology and water resources in the three catchments of Swaziland (Komati, Mbuluzi and Ngwavuma) has been evaluated using General Circulation Model results (rainfall, potential evapotranspiration, air temperature etc.) as inputs to a rainfall runoff model. Three General Circulation Models (GCMs) namely: Canadian Climate Change Equilibrium (CCC-EQ); Geophysical Fluid Dynamics Laboratory (GFDL) and United Kingdom Transient Resilient (UKTR) were found appropriate for use to project the temperature and precipitation changes for Swaziland for year 2075. This information was used to generate the temperature, precipitation and potential evapotranspiration values for the three catchments for year 2075 which was input into a calibrated WatBall rainfall runoff model. Simulation results without taking into consideration of water use projections show that there will be high flows during the summer months but low flows during the winter months. Simulation results after taking into consideration of water use projections show a water deficit from June to September in both the Komati, and Ngwavuma catchments and a water deficit from May to September in the Mbuluzi catchment. This means that the environmental water needs and Swaziland's water release obligation in the three catchments to South Africa and Mozambique will not be met during the winter months under expected climate change conditions.     

气候变化与清洁发展机制（五）

1CDM项目开发根据《马拉喀什协定》,一个典型的CDM项目从开始准备到实施,并最终产生减排量,需要经历如下一些主要阶段：（1）项目识别（2）项目设计（3）参与国的批准（4）项目审定（5）项目注册     

气候变化与清洁发展机制(三)

1EU-ETS简介为了履行《京都议定书》规定的减排目标,欧盟启动全球第一个温室气体排放交易体系——欧盟温室气体排放交易体系(European Union Emission Trading Scheme,简称EU-ETS)。自2005年1月运行以来,EU-ETS已发展为全球最大的温室气体排放交易体系。     

气候变化与清洁发展机制（一）

1气候变化与清洁发展机制简介二氧化碳（CO2）、甲烷（CH4）、及氟利昂（CFC）等气体通过吸收地球表面反射的太阳能红外线而温暖大气,从而避免地球表面温度的急剧变化,使地球表面的平均温度保持在15℃左右以适合人类生活。     

气候变化与清洁发展机制(七)

1CDM项目开发本期继续为大家介绍CDM项目开发的八个阶段中的第三、第四阶段:参与国的批准和项目审定。参与国的批准所谓批准是指参与项目的各缔约方批准该项目作为CDM项目,而非一般意义上的项目批准。根据规定,一个CDM项目要进行注册,必须由参加该项目的每个缔约方的国家清洁发展机制主管机构出具该缔约方自愿     

气候变化与清洁发展机制(四)

1VERs简介自愿减排市场(Voluntary Carbon Market)是一个不属于《京都议定书》体制内,但与CDM平行的碳交易市场,其产生的是自愿减排量VERs(Voluntary Emission Reduction,简称VERs)。VERs市场(如芝加哥气候交易所CCX)与强制碳交易市场(如EUETS)相比,也是对CDM市场的有益补充。     

气候变化与清洁发展机制(二)

1碳交易碳交易是建立在《Kyoto Protocol京都议定书》基础上的一种温室气体减排交易。《京都议定书》首先确定了温室气体的种类:二氧化碳(CO2)、甲烷(CH4)、氧化亚氮(N2O)、氢氟碳化物(HFCs)、全氟化碳(PFCs)、     

Impacts of Climate Change on Water Resources Availability and Agricultural Water Demand in the West Bank

Global climate change is predicted as a result of increased concentrations of greenhouse gasses in the atmosphere. It is predicted that climate change will result in increasing temperature by 2 to 6°C and a possible reduction of precipitation of up to 16% in the Mediterranean basin. In this study, the West Bank is taken as a case study from the Mediterranean basin to evaluate the effects of such climate change on water resources availability and agricultural water demands. Due to the uncertainty in climate change impacts on temperature and precipitation, a number of scenarios for these impacts were assumed within the range of predicted changes. For temperature, three scenarios of 2, 4 and 6°C increase were assumed. For precipitation, two scenarios of no change and 16% precipitation reduction were assumed. Based on these scenarios, monthly evapotranspiration and monthly precipitation excess depths were estimated at seven weather stations distributed over the different climatic and geographical areas of the West Bank. GIS spatial analyses showed that the increase in temperature predicted by climate change could potentially increase agricultural water demands by up to 17% and could also result in reducing annual groundwater recharge by up to 21% of existing values. However, the effects of reduced precipitation resulting from climate change are more enormous as a 16% reduction in precipitation could result in reducing annual groundwater recharge in the West Bank by about 30% of existing value. When this effect is combined with a 6°C increase in temperature, the reduction in groundwater recharge could reach 50%.     

Impact of Spatial Data Availability on Climate Change Prediction in the Weyib River Basin in Ethiopia

Impact of spatial data availability on the temperature and precipitation prediction characteristics of Weyib River basin in Ethiopia has been investigated using CMIP5-CanESM2 model for the RCP8.5, RCP4.5 and RCP2.6 scenarios. The objective of the present study is to characterize how future temperatures and precipitation prediction under CMIP5-CanESM2 model output varies against diverse averaged arbitrary spatial weather stations found in the basin. The statistical downscaling model tested and verified using the observed daily data for twelve, six and three averaged arbitrary spatial weather stations as well as for a single weather station was used to predict the future climate scenarios. The results revealed that the mean annual daily maximum and minimum temperature and precipitation for twelve, six and three arbitrary spatial stations have revealed an increasing trend in the upcoming periods until the end of the century. In single station analysis, the trend itself has changed from increasing trend to decreasing trend in case of maximum and minimum temperature. In case of precipitation, no visible trend has been observed in case of single station analysis. Therefore, the variation in amount and distribution of precipitation and temperature among the four averaged spatial stations in the same study area might affect the water resources and agriculture of the basin and also instead of using a single weather station to predict future climate variables for a particular study basin, it is more reliable using averages of numerous spatial weather stations data.     

Assessment of Water Resources Vulnerability and Adaptation to Climate Change

This paper provides an overview of the 'standard' methodology developed for the United States Country Studies Program on the Assessment of Water Resources Vulnerability and Adaptation to Clim ate Change. The methodology is described in more detail in accompanying articles in this issue. A standard methodology was developed for two reasons. First, for countries with little or no experience in hydrologic and water resources modelling, it provided a simple, yet appropriate set of modelling tools that could be quickly learned and applied with a limited data set. Second, it provided a consistent methodology for synthesizing results for regional and global assessments as well as cross-country and cross-regional comparisons.     

Watershed Modeling to Assessing Impacts of Potential Climate Change on Water Supply Availability

Climate change could have impacts on hydrologic systems threatening, availability of water supply resources. In Illinois, regional water supply planning efforts are attempting to better understand potential impacts on low flow and surface water availability through analysis of hydrologic sensitivity to a range of climate scenarios. This paper explores the development, calibration and validation of Fox River watershed model using the soil and water assessment tool (SWAT) and the model’s application to assess impacts of potential climate change. The watershed model is calibrated and validated using daily flow records at three gauging stations. Automatic model calibration followed by manual refinement of parameter values was performed. Calibration results were generally good for monthly and annual time step but only satisfactory for daily simulations. Based on simulations of global climate models produced for IPCC fourth assessment report, climate scenarios were prepared by the Illinois State Water Survey for water supply planning initiatives in north-east and east-central Illinois. These scenarios showed ranges of temperature change between 0°C to +3.3°C and annual precipitation changes between −127 to +127 mm in the next 50 years, excluding the 5% extreme ends of those climate model simulations considered. Changes in climate were reflected using adjustments to the historical record, instead of using direct outputs from individual climate models. The watershed model was used to assess the impact of potential climate change. Application results indicate that annual precipitation change of 127 mm on average increases annual water yield and 7-day low flows by 28% and 19%, respectively. In contrast, a temperature change of +3.3°C results in average reductions of annual water yield by 13% and 7-day low flows by 10%. Seasonal effects were investigated through evaluation of changes in average monthly flows. Increasing precipitation resulted in significant changes in streamflows in late summer and fall months where as increasing temperature greatly affects winter flows due to snowmelt. The key implication is that climate change-induced variability of streamflows could have major impacts on water supply availability in the Fox River watershed and in particular, increased periods of drought could result in deficit of supplies during seasons of peak water use. It must be noted that this analysis does not examine the potential impacts of population growth and water use on water supply availability, which are also expected to have substantial influences in the region.     

Evaluation of Socio-Economic Factors that Determine Adoption of Climate Compatible Freshwater Supply Measures at Farm Level: a Case Study in the Southwest Netherlands

The availability of freshwater resources in soil and groundwater bodies in the southwestern part of The Netherlands is expected to decrease during the agricultural growing season because of an expected increase of freshwater demands and a changing climate. This expected shortage of fresh water might negatively affect agricultural production. To cope with this problem, three pilots were initiated aimed at increasing freshwater supply at farm-level. The objective of this paper is to evaluate the socio-economic factors that determine the wider use of the measures investigated in these pilots. Therefore, the results of a feasibility study and a survey about drought risks were compared. The survey indicates that respondents do not make distinction between a dry and extremely dry year in their estimation of the return period. The results of a feasibility study illustrate that confidence and the level of common understanding regarding the reliability of these innovative measures has increased amongst project participants since 2012. The survey respondents were less optimistic about the wider implementation of the investigated technologies. A reliable freshwater supply and supportive legislation are the most decisive socio-economic factors for a future investment in additional freshwater supply for farmers in this region. Both studies illustrate that the impact of additional freshwater supply on farm economics strongly depends on farm type and crop cultivation plan. These insights may support the wider use of these innovations and may help to improve agro-hydrological models.     

Sustainability of Small Reservoirs and Large Scale Water Availability Under Current Conditions and Climate Change

Semi-arid river basins often rely on reservoirs for water supply. Small reservoirs may impact on large-scale water availability both by enhancing availability in a distributed sense and by subtracting water for large downstream user communities, e.g. served by large reservoirs. Both of these impacts of small reservoirs are subject to climate change. Using a case-study on North-East Brazil, this paper shows that climate change impacts on water availability may be severe, and impacts on distributed water availability from small reservoirs may exceed impacts on centralised water availability from large reservoirs. Next, the paper shows that the effect of small reservoirs on water availability from large reservoirs may be significant, and increase both in relative and absolute sense under unfavourable climate change.     

Streamflow Forecast and Reservoir Operation Performance Assessment Under Climate Change

This study attempts to investigate potential impacts of future climate change on streamflow and reservoir operation performance in a Northern American Prairie watershed. System Dynamics is employed 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. The second version of the Canadian Centre for Climate Modelling and Analysis Coupled Global Climate Model is selected to generate the climate change scenarios with daily climatic data series for hydrologic modeling. Watershed-based hydrologic and reservoir water dynamics modeling focuses on dynamic processes of both streamflow generation driven by climatic conditions, and the reservoir water dynamics based on reservoir operation rules. The reliability measure describes the effectiveness of present reservoir operation rules to meet various demands which are assumed to remain constant for the next 100 years in order to focus the study on the understanding of the structure and the behaviour of the water supply. Simulation results demonstrate that future climate variation and change may bring more high-peak-streamflow occurrences and more abundant water resources. Current reservoir operation rules can provide a high reliability in drought protection and flood control.     

气候变化背景下中国绿色水电评估体系探究

为了减缓温室气体排放、应对气候变化影响,以水电清洁能源与生态环境相互协调发展为核心的绿色水电评估成为研究热点。基于国内外绿色水电研究现状,提出以国际绿色水电认证体系、我国现行技术标准为基础,从防洪、航运、能源、生态环境、移民生态补偿、库区文化景观补偿等角度出发,分析长江上游典型区域梯级水电工程建设、运行各阶段对环境、经济、社会的影响,提炼出具有完备性、独立性、代表性、可比性、可操作性的指标体系,探寻我国绿色水电评价指标及其阈值。通过选择具有代表性的典型案例进行试点评估,建立覆盖水电工程项目全生命周期的生态保护-经济效益-社会影响评估体系,以保证我国水电工程项目建设中每个环节的“绿色性”,促进我国水电清洁能源的可持续发展。     

The Transboundary Impacts of Trade Liberalization and Climate Change on the Nile Basin Economies and Water Resource Availability

A multi-country, multi-sector computable general equilibrium (CGE) model is used for the first time to evaluate the economic and water resource availability effects of trade liberalization (removal of import tariffs) and facilitation (reducing non-tariff barriers) under climate change in the Nile Basin. The analysis uses the GTAP 9 Database and the GTAP-W model that distinguishes between rainfed and irrigated agriculture and implements water as a factor of production directly substitutable in the production process of irrigated agriculture. A full trade liberalization and improved trade facilitation scenario is considered with and without climate change. The study reveals that trade liberalization and facilitation generates substantial economic benefits and enhances economic growth and welfare in the Nile basin. The effect of instituting a free trade policy on water savings is found to be limited, while climate change improves water supply and hence irrigation water use, enhancing economic growth and welfare in the basin.     

Assessment of Water Resources Availability and Groundwater Salinization in Future Climate and Land use Change Scenarios: A Case Study from a Coastal Drainage Basin in Italy

The joint effect of changes in climate and land use on the future availability of water resources was assessed under the SRES A1B and A2 climate scenarios as well as five land use scenarios for the 2080–2100 time-frame in an Italian coastal watershed. The study area is a small coastal polder (100 km²) characterized by irrigated agriculture, urban expansion, drainage, quarrying and sensitivity to salt-water intrusion. The hydroclimatic budget and the GALDIT index have been computed for assessing water resources availability and groundwater vulnerability to salinization, respectively. The methodology developed is integrated into a tool based on Excel?, which supported the development of scenarios in participatory processes. The conclusions emerged from the analysis are the following: (1) climate change is more effective than land use change in controlling future freshwater availability and amplifies the imbalance between winter surplus and summer deficits, (2) freshwater availability in the summer will likely be affected by an increase in evaporation from open water surfaces due to increased temperature, whereas winter surplus would increase, (3) the vulnerability of the coastal aquifer to salinization will probably moderately increase but an inherent limitation of the GALDIT index to land use change parameters prevents a sound assessment. Strategies that may be proposed to administrators and stakeholders are based on increasing storage of seasonal water surplus.     

An Assessment of Climate Change,Water Resources,and Policy Research

ABSTRACT

A significant climate change can affect water resources and result in social and/or environmental impacts that can become policy issues. Review of the research in this emerging field of climate, water and policy reveals certain key issues that affect the transfer of information to policymakers. It also reveals the necessity for interdisciplinary analyses, a lack of information about parts of the hydrologic cycle, and the limited views many hydrologists have about climate changes and how to deal with them. The emphasis of recent research has been on effects on precipitation of CO, induced global warming on how climate changes might alter extreme events (droughts and floods), the relationship of climate alterations and water quality, and development of methods to better ascertain linkages of climate, water, and society. Policymakers attempting to address the effects of climate change on water resources generally ask six questions including: (1) the type of climate change apt to occur; 2) the changes beyond our recent (100-year) experience; 3) whether the changes can be predicted; 4) the certainty of change/s predicted; 5) the effects (social and environmental) that will occur; and (6) the potential adjustments needed.

Efforts to address adequately these questions are often hindered by four problem areas that need attention. First, climate impacts research is still in the developmental stage. Second, knowledge about certain hydrologic cycle variables is lacking and in particular, the interactions between climate and water quality. Third, many hydrologists assume stationarity in climate and find it difficult to accept and utilize climate change concepts. Finally, the impact of information on climate-water issues on the policy process is less than adequate often because scientists poorly understand the policy process.