Integrating a Climate Change Assessment Tool into Stakeholder-Driven Water Management Decision-Making Processes in California

There is an emerging consensus in the scientific community that climate change has the potential to significantly alter prevailing hydrologic patterns in California over the course of the 21st Century. This is of profound importance for a system where large investments have been made in hydraulic infrastructure that has been designed and is operated to harmonize dramatic temporal and spatial water supply and water demand variability. Recent work by the authors led to the creation of an integrated hydrology/water management climate change impact assessment framework that can be used to identify tradeoffs between important ecosystem services provided by the California water system associated with future climate change and to evaluate possible adaptation strategies. In spite of the potential impact of climate change, and the availability of a tool for investigating its dimensions, actual water management decision-making processes in California have yet to fully integrate climate change analysis into their planning dialogues. This paper presents an overview of decision-making processes ranked based on the application of a 3S: Sensitivity, Significance, and Stakeholder support, standard, which demonstrates that while climate change is a crucial factor in virtually all water-related decision making in California, it has not typically been considered, at least in any analytical sense. The three highest ranked processes are described in more detail, in particular the role that the new analytical framework could play in arriving at more resilient water management decisions. The authors will engage with stakeholders in these three processes, in hope of moving climate change research from the academic to the policy making arena.     

邯郸市区不同下垫面降雨径流水质变化特征研究

为缓解邯郸市城区水资源供需矛盾,合理利用雨洪资源,在对生活区屋面、城区道路、公园绿地降雨径流水质进行检测的基础上,分析了雨水径流中主要污染物的变化过程,探讨降雨径流水质受环境条件影响情况。通过研究得出城区初期雨水径流污染最为严重,随降雨历时的延长,污染物浓度逐渐下降并趋于稳定。不同城区下垫面雨水径流污染物含量差异明显,城区主干道路降雨径流水质最差。     

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%.     

A Semi-Distributed Monthly Water Balance Model and its Application in a Climate Change Impact Study in the Middle and Lower Yellow River Basin

Abstract

Human activities and climatic change have greatly impacted hydrological cycles and water resources planning in the Yellow River basin. In order to assess these impacts, a semi-distributed monthly water balance model was proposed and developed to simulate and predict the hydrological processes in the middle and lower Yellow River basin. GIS techniques were used as a tool to analyze topography, river networks, land-use, human activities, vegetation, and soil characteristics. The model parameters were calibrated in 35 gauged sub-basins in the middle Yellow River, and then the relationships between the model parameters and the basin physical characteristics were established. A parameterization scheme was developed in which the model parameters were estimated for each grid element by regression and optimization methods. Based on the different outputs of general circulation models (GCMs) and regional climate models (RCMs), the sensitivities to global warming of hydrology and water resources for the Yellow River basin were studied. The proposed models are capable of producing both the magnitude and timing of runoff and water resources conditions. The runoffs are found to be very sensitive to temperature increases and rainfall decreases. Results of the study also indicated that runoff is more sensitive to variation in precipitation than to increase in temperature. The additional uncertainty of climate change has posed a challenge to the existing water resources management practices, and the integration of water resources management will be necessary to enhance the water use efficiency in the Yellow River basin.     

Climate Change and Resource Management in the Columbia River Basin

Abstract

Scenarios of global climate change were examined to see what impacts they might have on transboundary water management in the Columbia River basin. Scenario changes in natural streamflow were estimated using a basin hydrology model. These scenarios tended to show earlier seasonal peaks, with possible reductions in total annual flow and lower minimum flows. Impacts and adaptation responses to the natural streamflow scenarios were determined through two exercises: (a) estimations of system reliability using a reservoir model with performance measures and (b) interviews with water managers and other stakeholders in the Canadian portion of the basin. Results from the two exercises were similar, suggesting a tendency towards reduced reliability to meet objectives for power production, fisheries, and agriculture. Reliability to meet flood control objectives would be relatively unchanged in some scenarios but reduced in others. This exercise suggests that despite the high level of development and management in the Columbia, vulnerabilities would still exist, and impacts could still occur in scenarios of natural streamflow changes caused by global climate change. Many of these would be indirect, reflecting the complex relationship between the region and its climate.     

呼伦湖水生态环境遥感监测及其对气候变化的响应

以位于内蒙古的第一大湖-呼伦湖为研究对象,综合应用RS、GIS等现代分析技术手段,通过解译该区1973、1975、1986～2009年近36a的MSS、TM、ETM遥感影像,实现了呼伦湖湖泊水位、面积的遥感动态监测,并建立了关系模型：研究发现呼伦湖面积在1999年达到了1959年以来的最大水面面积2106．95km2后开始骤然下降到2009年的最低水面面积1813．69km2。以24．44km2／a的速度减少了293．26km2,水面面积比1999年最大面积时减少了近14％。水位高程自1999年的最高水位下降了3．94m,是呼伦湖平均水深（9m）的39．4％。收集、整理了呼伦湖及上游流域4个气象站点、3个水文站点近52a的气象、水文资料。分析了呼伦湖区域尺度内的水热状况变化,发现研究区域温度升高。降水呈波动性减少．并且在1999年后温度和降水的变率增大,是呼伦湖面积减小、水位下降的主要原因。最后．分析了气候变化对呼伦湖生态环境的影响效应。并建立了湖泊水位和降水、气温等气象因子以及径流量之间的关系模型．研究可为寒旱区湖泊水环境管理提供参考。     

径流对气候变化响应的定量分析研究

全球变暖导致的水文水资源问题越来越突出,已成为全社会关注的焦点问题之一。本文选择河南省境内5个水文站、44个气象站的气象资料,对径流对气候变化的响应运用多元回归方法作了定量分析,结果表明:年、月径流随降水量的增加而增加;随着平均气温的升高而减少。降水量越少,温度越高,则径流越少;反之降水量越多,温度越低,则径流越多。不同流域的月径流变化对各种气候变化情景的响应表现出一定的差异性,且差异相对年径流变化较小。     

Impacts of Global Climate Change Scenarios on Water Supply and Demand in Jordan

Abstract

The potential impact of global climate change is one of the least addressed factors in water resources planning in developing countries. The potential impacts of climate change are examined for Jordan, where a methodology is presented for improved management of water demand under the uncertainties associated with climate change. A temperature/precipitation sensitivity model is constructed and combined with water demand forecasts to project deficits for the year 2020. Deficit reducing options are then evaluated in terms of social and economic viability. The study concludes that only some of the deficits may be alleviated, illustrating the significance of considering climate change in planning for countries that already experience water imbalances.     

Quantifying the Urban Water Supply Impacts of Climate Change

The difference in timing between water supply and urban water demand necessitates water storage. Existing reservoirs were designed based upon hydrologic data from a given historical period, and, given recent evidence for climatic change, may be insufficient to meet demand under future climate change scenarios. The focus of this study is to present a generally applicable methodology to assess the ability of existing storage to meet urban water demand under present and projected future climatic scenarios, and to determine the effectiveness of storage capacity expansions. Uncertainties in climatic forcing and projected demand scenarios are considered explicitly by the models. The reservoir system in San Diego, California is used as a case study. We find that the climate change scenarios will be more costly to the city than scenarios using historical hydrologic parameters. The magnitude of the expected costs and the optimal investment policy are sensitive to projected population growth and the accuracy to which our model can predict spills.     

Impacts of Climate Change and Human Activities on the Surface Runoff in the Tarim River Basin over the Last Fifty Years

The impacts of climate change and human activities on the surface runoff were analyzed by the Mann–Kendall and trend analysis methods based on the hydrological, meteorological and socioeconomic data over the last 50 years in the Tarim River basin. Results show that the runoff in the headstreams increased but that in the mainstreams decreased significantly during the past 50 years. The former is a response to climate change, and the later is due to human activities. The surface runoff in the mainstreams decreased by 41.59, 63.77 and 75.15% in the 1970s, 1980s and 1990s, respectively, as compared to that without being disturbed by human activities in the same period. The main human activities are the irrigated agriculture combined with population increase in the region. As a consequence, the ecosystem in the lower reaches of Tarim River has degenerated, largely owing to inappropriate allocation of water resources.     

气候变化情景下黄河天然径流预测研究

1961—2000年黄河天然径流量呈减小趋势,且径流变化与降水量变化过程基本一致。选用IPCC提出的A2、B2两种温室气体排放方案,并采用北京大学在黄河流域未来气候情景研究中的降尺度成果,以黄河流域未来气候情景模式和预测成果为基础,建立黄河水量平衡模型,预测黄河主要断面的未来天然径流量并分析其时空变化。结果表明:黄河径流量2050年将减少29.3亿～61.1亿m3,2100年将减少42.2亿～71.2亿m3;从空间分布来看,上游兰州以上主要产水区的降水量、径流量有较大幅度减小,其他区域产流量有所增加;从径流年内分配来看,冬季、春季略有增加或基本不变,夏季、秋季减少明显。     

Modelling the Effects of Climate Change on Water Resources in Central Sweden

This article describes investigationsinto the effects of climate change on flow regimes oftwenty-five catchments (from 6 to 1293 km²) incentral Sweden. Hydrological responses of fifteenhypothetical climate change scenarios (e.g.combinations of T = +1, +2 and +4 °C andP = 0, ± 10%, ± 20%) were simulated by a conceptual monthly water balance model. The results suggest thatall the hypothetical climate change scenarios wouldcause major decreases in winter snow accumulation.Significant increase of winter flow and decrease ofspring and summer runoff were resulted from mostscenarios. Attendant changes in actualevapotranspiration were also examined for all climatechange scenarios. Despite the changes in seasonaldistribution of evapotranspiration, the change inannual total evapotranspiration was relatively smallwith the maximum change of 23% compared with the 76%for mean annual snow water equivalent changes and 52%for mean annual runoff changes. Such hydrologicresults would have significant implications on futurewater resources design and management.     

拉萨河流域径流对土地利用和气候变化的响应分析

拉萨河流域处青藏高原中南部,因其独特的地理位置是对气候变化较为敏感的区域之一,同时也是青藏高原人口和耕地较为密集区域.在建立SWAT模型对拉萨河流域水循环过程进行模拟的基础上,通过设置不同气候情景与土地利用状况,分析近30 a来拉萨河流域径流变化的成因,并研究径流对气候因子变化的敏感性.结果表明:①气候变化与土地利用对...     

三峡蓄水对局地气候变化的影响

大型水体会对局部地区(局地)气候条件造成影响,三峡工程是当今世界规模最大的水利水电枢纽工程,为了分析三峡蓄水对当地气候变化的影响,以三峡库区10个站点为研究对象,利用气候倾向率、CVM检验等方法,系统分析了三峡库区66 a来气候变化特征以及蓄水对局地气候变化的影响。结果表明,三峡蓄水后局地温度下降,影响大坝附近299.83 km²的地区,影响距离最远距大坝12.65 km,大坝最近的秭归站温度在1997年发生突变,蓄水后20 a秭归站年平均温度较蓄水前20 a下降1.15 ℃;蓄水造成局地降水量增加,影响大坝附近2 914.88 km²的地区,影响距离最远距大坝109.15 km,大坝最近的秭归站降水在1997年突变,蓄水后20 a秭归站平均降水量较蓄水前上升245.90 mm;蓄水造成局地相对湿度增加,秭归、兴山站相对湿度分别在1997年、2003年突变,蓄水后20 a秭归站相对湿度较蓄水前20 a上升5.29%;蓄水造成局地日照时数下降,影响大坝附近2 045.66 km²的地区,影响距离距大坝最远41.06 km,距大坝最近的秭归站日照时数在2002年突变,蓄水后20 a秭归站日照时数较蓄水前20 a下降33.87 h。蓄水对气象要素影响的范围较小,对各要素共同造成影响的范围仅75.27 km²,各要素全部在蓄水期间发生突变的仅秭归一站。     

气候变化对水资源影响的研究现状与展望

随着科技的发展、人口的激增,人类活动已经触及到地球的方方面面。温室气体的大量排放导致了近年来气候变化无常,也对水资源方面造成很大的影响,同时也对人类生活和自然生态方面造成了许多负面影响。本文综述了当前气候变化对流域水资源量、干旱洪涝频率、水质、农业灌溉水量等4方面的影响,综合考虑了国内国外的研究现状,并对未来研究方向提出一定的预想。     

Analysis of Climate Change Characteristics of Shanxi Province in Recent 54 Years

提 要：利用陕西省1960-2013年的气温和降水资料,分析了气温和降水时空变化特征。结果表明：(1)在时间尺度上,陕西省的年平均气温的上升速率约为0.23 ℃/10a,90年代后期以来,气温显著升高。四季气温也呈上升趋势,其中春、冬季上升速率较大。年降水量以8.78 mm/10a的速率下降,80年代后期以来,降水量明显减少。春、秋季降水量呈下降趋势,夏、冬季呈上升趋势。年平均气温在1996年发生突变,1996年以来为高温期,年降水量在1970年和1975发生突变,1970年以来为相对少雨期,陕西省气候趋于暖干化。(2)在空间尺度上,年平均气温由南向北递减,呈现出明显的纬度地带性特征。年降水量整体由南向北递减,部分山地形成地形雨。     

坡地自然降雨入渗产流的数值模拟

从动量定理和水量平衡原理出发,推导出自然降雨条件(即同时考虑变雨强、降雨动量和风影响下的坡地径流过程)下的坡地径流基本方程。在考虑一般问题定解条件的基础上,采用Preissmann隐式格式对模型进行数值求解。利用在江西省水土保持生态科技园内的10组实测资料对模型进行了验证,其计算值与实测值的相对误差不超过±11％;说明模型的计算结果是可靠的,提出的自然降雨条件下坡地径流模型是可行的。     

人类活动影响下的洛河产汇流特性变化

洛河位于黄河小浪底至花园口区间,是黄河十大支流之一,也是黄河下游主要的暴雨洪水来源区。60年代以后兴建了大量水利水保工程,流域下垫面发生了显著变化,流域产流特性发生了较大变化。相同降雨条件下,径流量和洪峰流量大幅度减少;大洪水发生的次数在不断减少,但如果遭遇大暴雨,仍可能出现大洪水。     

Analysis of Storm Water Runoff Impact on Water Quality of Dishui Lake in New Harbour Town, Shanghai

1 IntroductionThe Shanghai Municipality Government is planning a har-bour town,on the coast southeast of Shanghai , will be one ofprospective . The city centre of the new harbour town will be amixedland-use catchment with residential ,commercial ,and e-du…     

气候变化对可可西里盐湖流域湖泊水量变化的影响分析

湖泊是气候变化的敏感指示器。为了研究气候变化对湖泊水量的影响,以盐湖流域为研究区,应用统计方法对1989—2018年降雨、气温、蒸发进行线性趋势和突变分析,采用多源卫星遥感技术对湖泊面积等水文要素进行监测,分析湖泊面积与气象要素、湖泊面积与湖泊水量之间的相关性。利用VIC模型模拟径流并结合计算的冰川水量得到盐湖径流组成,定量探讨气象要素对湖泊水量变化的影响,综合分析2011年前后气象要素影响流域湖泊水量的差异。结合统计分析与水文模型定量计算可知:年降雨量、年平均气温显著升高,年蒸发量呈下降趋势,且与湖泊面积有较好的相关性。湖泊面积与湖泊水量间相关性较高,可间接体现气象要素对湖泊水量变化的影响。2011年前卓乃湖和盐湖水量变化主要受降雨量影响,库赛湖和海丁诺尔湖水量变化主要受气温影响;2011—2014年4个湖泊水量变化主要受降雨量影响;2015—2018年4个湖泊水量变化中降雨增加量、冻土释水和地下水补给增加量、冰川融水量对湖泊扩张的贡献约为34.48%、57.66%、7.86%,气温变化成为影响湖泊水量变化的主要因素,降雨量影响次之。