气候变化背景下水资源脆弱性研究与展望

论述了气候变化背景下水资源脆弱性概念、内涵及其与适应性管理的联系;综述了水资源脆弱性定量评估方法,包括指标权重法、函数及综合指标法等;介绍了减少水资源脆弱性的适应对策研究。分析表明,联系水资源供需矛盾的水资源脆弱性既有自然变化脆弱性的一面,又有气候变化影响导致水资源供需关系发生变化以及旱涝灾害影响加剧水资源脆弱性的问题。关键是要识别影响水资源脆弱性变化的主要调控变量,通过应对气候变化的适应性对策研究,最大限度地减少水资源脆弱性。未来气候变化背景下水资源脆弱性研究,将在进一步发展脆弱性影响与评估基础上,逐步转到适应性水资源管理与对策的研究。     

Vulnerability and adaptation in a dryland community of the Elqui Valley, Chile

Livelihoods in drylands are already challenged by the demands of climate variability, and climate change is expected to have further implications for water resource availability in these regions. This paper characterizes the vulnerability of an irrigation-dependent agricultural community located in the Elqui River Basin of Northern Chile to water and climate-related conditions in light of climate change. The paper documents the exposures and sensitivities faced by the community in light of current water shortages, and identifies their ability to manage these exposures under a changing climate. The IPCC identifies potentially increased aridity in this region with climate change; furthermore, the Elqui River is fed by snowmelt and glaciers, and its flows will be affected by a warming climate. Community vulnerability occurs within a broader physical, economic, political and social context, and vulnerability in the community varies amongst occupations, resource uses and accessibility to water resources, making some more susceptible to changing conditions in the future. This case study highlights the need for adaptation to current land and water management practices to maintain livelihoods in the face of changes many people are not expecting.     

气候变化和水的最新科学认知

政府间气候变化专门委员会（IPCC）于2008年4月8日正式通过了"气候变化和水"技术报告。该报告建立在IPCC 3个工作组第四次评估报告的基础上,客观、全面而审慎地评估了与水有关的气候变化以及对水的过去、现在和未来的认知。最重要的进展是：过去几十年观测到全球变暖已经与大尺度水文循环的大规模变化联系在一起;气候模型对21世纪的模拟结果一致显示出降水在高纬和部分热带地区将增加,而在部分亚热带和中低纬地区将减少的结果;预计到21世纪中期,河流年平均径流和水量可能会因为高纬和部分湿润热带地区的气候变化而增加,而在中低纬和干旱热带将可能减少;许多地方降水强度和变率的增加将使洪旱危险性上升;预计冰雪储藏的水的补给将在本世纪减少;预计较高的水温和极端变化,包括洪旱等,将影响水质并加剧水污染;对全球而言,气候变化对淡水系统负面影响将超过收益;预计由于气候变化导致的水量-水质变化将影响食物的产量、稳定性、流通和利用;气候变化影响现有水的基础设施的功能和运行,包括水电、防洪、排水、灌溉系统,同时影响到水的管理;目前的水管理措施不足以应对气候变化的影响;气候变化挑战"过去水文上的经验能得到未来的情况"的传统说法;为保障平水和干旱情况所设计的适应选择,必须综合需水和供水双方的战略;减缓措施可以降低升温对全球水资源的影响程度,进而减低适应的需求;水资源管理明显地影响到很多其他政策领域。     

全球变暖背景下的气候服务

气候与人的关系密不可分.气候学本身就是人类认识自然、利用气候的科学.最近五十多年,地球气候明显地受到了人类活动的影响,而变化的气候又通过各种途径影响人类的生产和生活.21世纪人类必须高度重视并积极应对气候变化及与其相伴随的各种极端天气气候事件.通过进一步加强气候监测,加强气候科学研究和模式研发,迅速提升气候预测能力,并通过加强建立与用户之间的伙伴关系,建立气候服务系统,从而不断提高服务水平,以适应日趋严峻的气候变化.     

Role of Education and Training in Agricultural Meteorology to Reduce Vulnerability to Climate Variability

Agricultural meteorologists are concerned with many operational aspects of the effects of climate on crop production, livestock, and natural resource management. For them to continue to make a contribution to the economy of a country they must continually sharpen their skills and remain updated on the latest available information. Training should include a variety of skills, including transferable skills (e.g. communication, numeracy), professional skills (including cognitive skills) and information technology skills. Problem-based learning can be used to promote critical thinking, decision making and analytical skills. More use should be made of computer-aided learning for agricultural meteorologists’ in-service training. In particular, the Internet or CDs could be used to disseminate specific recently developed techniques and applications to improve the understanding of the variability in climate and its effect on agricultural production and natural resource management. Examples that can address the vulnerability of farmers include crop–climate matching, the use of indices, crop modelling and risk assessment together with seasonal outlooks. A strategy needs to be formulated to address these needs and implement changes in the education and training of agricultural meteorologists. These training needs must be constantly updated to meet the changing demands of new technology to cope with climate change and climate variability.     

Climate change impacts on Laurentian Great Lakes levels

Scenarios of water supplies reflecting CO₂-induced climatic change are used to determine potential impacts on levels of the Laurentian Great Lakes and likely water management policy implications. The water supplies are based on conceptual models that link climate change scenarios from general circulation models to estimates of basin runoff, overlake precipitation, and lake evaporation. The water supply components are used in conjunction with operational regulation plans and hydraulic routing models of outlet and connecting channel flows to estimate water levels on Lakes Superior, Michigan, Huron, St. Clair, Erie, and Ontario. Three steady-state climate change scenarios, corresponding to modeling a doubling of atmospheric CO₂, are compared to a steady-state simulation obtained with historical data representing an unchanged atmosphere. One transient climate change scenario, representing a modeled transition from present conditions to doubled CO₂ concentrations, is compared to a transient simulation with historical data. The environmental, socioeconomic, and policy implications of the climate change effects modeled herein suggest that new paradigms in water management will be required to address the prospective increased allocation conflicts between users of the Great Lakes.GLERL Contribution No. 645.     

Impact of Climate Change and Variability on Irrigation Requirements: A Global Perspective

Anthropogenic climate change does not only affect water resources but also water demand. Future water and food security will depend, among other factors, on the impact of climate change on water demand for irrigation. Using a recently developed global irrigation model, with a spatial resolution of 0.5° by 0.5°, we present the first global analysis of the impact of climate change and climate variability on irrigation water requirements. We compute how long-term average irrigation requirements might change under the climatic conditions of the 2020s and the 2070s, as provided by two climate models, and relate these changes to the variations in irrigation requirements caused by long-term and interannual climate variability in the 20th century. Two-thirds of the global area equipped for irrigation in 1995 will possibly suffer from increased water requirements, and on up to half of the total area (depending on the measure of variability), the negative impact of climate change is more significant than that of climate variability.     

Climate Change and Water Resources in Britain

This paper explores the potential implications of climate change for the use and management of water resources in Britain. It is based on a review of simulations of changes in river flows, groundwater recharge and river water quality. These simulations imply, under feasible climate change scenarios, that annual, winter and summer runoff will decrease in southern Britain, groundwater recharge will be reduced and that water quality – as characterised by nitrate concentrations and dissolved oxygen contents – will deteriorate. In northern Britain, river flows are likely to increase throughout the year, particularly in winter. Climate change may lead to increased demands for water, over and above that increase which is forecast for non-climatic reasons, primarily due to increased use for garden watering. These increased pressures on the water resource base will impact not only upon the reliability of water supplies, but also upon navigation, aquatic ecosystems, recreation and power generation, and will have implications for water quality management. Flood risk is likely to increase, implying a reduction in standards of flood protection. The paper discusses adaptation options.     

Stochastic Hydrology in the Context of Climate Change

Hydrologic trends, real (physical) or perceived (statistical), suggest that water management be predicated on the assumption of hydrologic nonstationarity. The assumption leaves open the question to what extent will the "trends" be sustained locally and regionally over the future 25, 50 or 100 years corresponding to the economic time horizons of water projects. Whether hydrologic trends are real or perceived, record events of hydrologic extremes, floods and droughts, will be broken with exceedingly high probabilities over the economic lives of water projects. Before the assumption of hydrologic nonstationarity is accepted, the ability to cope with the uncertain impacts of global warming on water management via the operational assumption of hydrologic stationarity should be carefully examined. In the absence of strong physical evidence, trends cannot be unequivocally distinguished from slow oscillations. Slow oscillations can be mimicked by persistence in stationary processes. It is time to examine the relative merits of the assumptions of stationarity and nonstationarity in the operational context of water management. The strategy of wait-and-see, i.e. delaying the making of important, expensive and essentially irreversible capital investments, could served water managers well in coping with the uncertainties regarding climate change.     

Adapting to Climate Impacts on the Supply and Demand for Water

The prospect of climate change adds to future water supply and demand uncertainties and reinforces the need for institutions that facilitate adaptation to changing conditions and promote efficient management of supplies and facilities. High costs and limited opportunities for increasing water supplies with dams, reservoirs, and other infrastructure have curbed the traditional supply-side approach to planning in recent decades. Although new infrastructure may be an appropriate response to climate-induced shifts in hydrologic regimes and water demands, it is difficult to plan for and justify expensive new projects when the magnitude, timing, and even the direction of the changes are unknown. On the other hand, evaluating margins of safety for long-lived structures such as dams and levees should consider the prospect that a greenhouse warming could produce greater hydrologic variability and storm extremes. Integrated river basin management can provide cost-effective increases in reliable supplies in the event of greenhouse warming. With water becoming scarcer and susceptible to variations and changes in the climate, demand management is critical for balancing future demands with supplies. Although regulatory and voluntary measures belong in a comprehensive demand management strategy, greater reliance on markets and prices to allocate supplies and introduce incentives to conserve will help reduce the costs of adapting to climate change. Federal water planning guidelines allow for consideration of plans incorporating changes in existing statutes, regulations, and other institutional arrangements that might be needed to facilitate water transfers and promote efficient management practices in response to changing supply and demand conditions.     

Seasonal and Inter-Annual Climate Forecasting: The New Tool for Increasing Preparedness to Climate Variability and Change In Agricultural Planning And Operations

Climate variability and change affects individuals and societies. Within agricultural systems, seasonal climate forecasting can increase preparedness and lead to better social, economic and environmental outcomes. However, climate forecasting is not the panacea to all our problems in agriculture. Instead, it is one of many risk management tools that sometimes play an important role in decision-making. Understanding when, where and how to use this tool is a complex and multi-dimensional problem. To do this effectively, we suggest a participatory, cross-disciplinary research approach that brings together institutions (partnerships), disciplines (e.g., climate science, agricultural systems science, rural sociology and many other disciplines) and people (scientist, policy makers and direct beneficiaries) as equal partners to reap the benefits from climate knowledge. Climate science can provide insights into climatic processes, agricultural systems science can translate these insights into management options and rural sociology can help determine the options that are most feasible or desirable from a socio-economic perspective. Any scientific breakthroughs in climate forecasting capabilities are much more likely to have an immediate and positive impact if they are conducted and delivered within such a framework. While knowledge and understanding of the socio-economic circumstances is important and must be taken into account, the general approach of integrated systems science is generic and applicable in developed as well as in developing countries. Examples of decisions aided by simulation output ranges from tactical crop management options, commodity marketing to policy decisions about future land use. We also highlight the need to better understand temporal- and spatial-scale variability and argue that only a probabilistic approach to outcome dissemination should be considered. We demonstrated how knowledge of climatic variability (CV), can lead to better decisions in agriculture, regardless of geographical location and socio-economic conditions.     

Climate Change Impacts for the Conterminous USA: An Integrated Assessment

Global climate change will impact the hydrologic cycle by increasing the capacity of the atmosphere to hold moisture. Anticipated impacts are generally increased evaporation at low latitudes and increased precipitation at middle and high latitudes. General Circulation Models (GCMs) used to simulate climate disagree on whether the U.S. as a whole and its constituent regions will receive more or less precipitation as global warming occurs. The impacts on specific regions will depend on changes in weather patterns and are certain to be complex. Here we apply the suite of 12 potential climate change scenarios, previously described in Part 1, to the Hydrologic Unit Model of the United States (HUMUS) to simulate water supply in the conterminous United States in reference to a baseline scenario. We examine the sufficiency of this water supply to meet changing demands of irrigated agriculture. The changes in water supply driven by changes in climate will likely be most consequential in the semi-arid western parts of the country where water yield is currently scarce and the resource is intensively managed. Changes of greater than ±50% with respect to present day water yield are projected in parts of the Midwest and Southwest U.S. Interannual variability in the water supply is likely to increase where conditions become drier and to decrease under wetter conditions.     

Impacts of Present and Future Climate Variability on Agriculture and Forestry in the Temperate Regions: Europe

Agriculture and forestry will be particularly sensitive to changes in mean climate and climate variability in the northern and southern regions of Europe. Agriculture may be positively affected by climate change in the northern areas through the introduction of new crop species and varieties, higher crop production and expansion of suitable areas for crop cultivation. The disadvantages may be determined by an increase in need for plant protection, risk of nutrient leaching and accelerated breakdown of soil organic matter. In the southern areas the benefits of the projected climate change will be limited, while the disadvantages will be predominant. The increased water use efficiency caused by increasing CO₂ will compensate for some of the negative effects of increasing water limitation and extreme weather events, but lower harvestable yields, higher yield variability and reduction in suitable areas of traditional crops are expected for these areas. Forestry in the Mediterranean region may be mainly affected by increases in drought and forest fires. In northern Europe, the increased precipitation is expected to be large enough to compensate for the increased evapotranspiration. On the other hand, however, increased precipitation, cloudiness and rain days and the reduced duration of snow cover and soil frost may negatively affect forest work and timber logging determining lower profitability of forest production and a decrease in recreational possibilities. Adaptation management strategies should be introduced, as effective tools, to reduce the negative impacts of climate change on agricultural and forestry sectors.     

气候变化对我国若干重大工程的影响

全球气候变化,特别是升温、降水强度增加以及极端天气气候事件频发,会通过影响重大工程的设施本身、重要辅助设备以及重大工程所依托的环境,从而进一步影响工程的安全性、稳定性、可靠性和耐久性,并对重大工程的运行效率和经济效益产生一定影响,气候变化还对重大工程的技术标准和工程措施产生影响。本文以青藏铁路（公路）工程、高速铁路工程、重大水利水电工程为典型工程阐述气候变化对重大工程的影响。青藏铁路（公路）沿线的冻土环境的热平衡极易打破,多年冻土环境一经破坏,难以恢复,气候变化已经使多年冻土环境发生变化,并且未来的多年冻土退化在全球变暖的背景下将变得更加严重。未来中国地区的地表气温、年平均降水量、台风等都将发生变化,极端天气气候事件频发,影响我国高速铁路的气候变化向着不利于高铁工程的趋势发展,将给高铁基础设施的服役寿命以及高铁运输秩序等方面带来影响。气候变化导致的温度变化、降水变化,改变了水资源的时空分布规律,对水工程和水安全在水量分配和调度、水资源利用和水文风险管理等产生影响。     

Tomorrow’s Forests: Adapting to A Changing Climate

Today’s forests are largely viewed as a natural asset, growing in a climate envelope, which favors natural regeneration of species that have adapted and survived the variability’s of past climates. However, human-induced climate change, variability and extremes are no longer a theoretical concept. It is a real issue affecting all biological systems. Atmospheric scientists, using global climate models, have developed scenarios of the future climate that far exceed the traditional climate envelope and their associated forest management practices. Not all forests are alike, nor do they share the same adaptive life cycles, feedbacks and threats. Much of tomorrow’s forests will become farmed forests, managed in a pro-active, designed and adaptive envelope, to sustain multiple products, values and services. Given the life cycle of most forest species, forest management systems will need to radically adjust their limits of knowledge and adaptive strategies to initiate, enhance and plan forests in relative harmony with the future climate. Protected Areas (IUCN), Global Biosphere Reserves (UNESCO) and Smithsonian Institution sites provide an effective community-based platform to monitor changes in forest species, ecosystems and biodiversity under changing climatic conditions.     

Using climate information for supporting climate change adaptation in water resource management in South Africa

Water resources, and in particular run-off, are significantly affected by climate variability. At present, there are few examples of how the water management sector integrates information about changing intra-annual climate conditions in a systematic manner in developing countries. This paper, using the case study of Cape Town in the Western Cape, South Africa, identifies processes and products to facilitate increased uptake of seasonal climate forecasts among water resource managers. Results suggest that existing seasonal forecasts do not focus enough on specific users’ needs. In order to increase uptake, forecasts need to include information on the likely impact of precipitation variability on runoff and water availability. More opportunities are also needed for those with climate knowledge to interact with water resource managers, particularly in the developing country context where municipal managers’ capacity is strained. Although there are challenges that need to be overcome in using probabilistic climate information, seasonal forecast information tailored to the needs of water resource planners has the potential to support annual planning and is therefore a means of adapting to climate change.     

Global-Scale Relationships between Climate and the Dengue Fever Vector, Aedes Aegypti

Considerable interest exists inthe potential role climate may play in human healthissues, especially regarding the effect of climatechange on vector-borne disease. The Aedesaegypti mosquito, the principal vector for dengue,considered the most important vector-borne viraldisease in the world, is particularly susceptible toclimate variability and climatic change. Here wepresent a modeling analysis focusing on global-scaleassociations between climate and the development,potential distribution, and population dynamics ofAe. aegypti. We evaluate the model by comparingand contrasting model data with observed mosquitodensities. There is good agreement between theobserved and modeled global distribution of themosquito; however, the model results suggest thepotential for increased latitudinal distributionsduring warmer months. Seasonal fluctuations inmosquito abundance also compare well to observed data. Discrepancies possibly reflect the relatively lowresolution of the climate data and model output andthe inability of the model to account for localmicroclimate effects, especially in coastal areas.Future modeling efforts will involve study ofinterannual variability in mosquito dynamics.     

Context Matters: What Shapes Adaptation to Water Stress in the Okanagan?

This paper describes two case studies of demand-side water management in the Okanagan region of southern British Columbia, Canada. The case studies reveal important lessons about how local context shapes the process of adaptation; in these cases, adaptation to rising and changing water demand under a regime of increasingly limited supply in a semi-arid region. Both case studies represent examples of water meter implementation, specifically volume-based pricing in a residential area and as a compliance tool in a mainly farming district. While the initiative was successful in the residential setting, agricultural metering met with stiff resistance. These cases suggest many factors shape the character of the adaptation process, including: interpretation of the signal relative to context, newness of the approach, consumer values, and local and provincial political agendas. Although context has been explored in resource management circles, thus far climate change adaptation research has not adequately discussed the embeddedness of adaptation. In other words, how context matters and what aspects of context, unrelated to climate change, could encourage or thwart the act of adapting. This study is a simple illustration of the potential drivers, barriers and enabling factors that have influenced the adaptation process of water management decisions in the Okanagan.     

气候变化对密云水库水资源的影响及其适应性管理对策

密云水库近30 a入库水资源量日益减少,严重影响城市供水和可持续发展,其中气候变化对水资源的影响成为最受关注的问题之一。以海河流域密云水库的水资源供应为例,研究了气候变化对入库水资源的影响。结果表明：除SRES A2情景下在2025年入库流量减少外,其他情景均表现为入库流量增加。对入库流量增加的情景,采用"零调整方案",即不采取调整措施是可以的,但由于未来北京水资源压力较大,有必要采取一些综合对策。通过多目标条件分析,为解决北京的饮用水供应问题,建议采用开源（跨河流调水）、节流（水田改旱地）及污水治理三管齐下的方案。     

Climate change in mountain regions: some possible consequences in the Moroccan High Atlas

Mountain areas are particularly sensitive to climate change. Seasonal and annual variations in climate already strongly influence agro-ecosystems, and although there is much speculation about the precise effects in such areas, any response of the communities will emerge from existing coping practices. Using examples from the High Atlas in Morocco, the paper explores the implications for livestock management, arboriculture and tourism. Although the local agro-ecosystem may prove resilient initially, the need to change tenure conditions and other rules of management may lead to conflict which exceeds the capacity of local institutions to resolve. At the same time national considerations may also draw the state more fully into conflict with mountain communities over resource use. However, the paper argues that these issues are just as likely to emerge from the evolution of the national economy as from climate change.