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1.
Climate change presents a significant planning challenge for water management agencies in the western United States. Changing precipitation and temperature patterns will disrupt their supply and extensive distribution systems over the coming decades, but the precise timing and extent of these impacts remain deeply uncertain, complicating decisions on needed investments in infrastructure and other system improvements. Adaptive strategies represent an obvious solution in principle, but are often difficult to develop and implement in practice. This paper describes work helping the Inland Empire Utilities Agency (IEUA) explicitly develop adaptive policies to respond to climate change and integrating these policies into the organizations' long-range planning processes. The analysis employs Robust Decision Making (RDM), a quantitative decision- analytic approach for supporting decisions under conditions of deep uncertainty. RDM studies use simulation models to assess the performance of agency plans over thousands of plausible futures, use statistical “scenario discovery” algorithms to concisely summarize those futures where the plans fail to perform adequately, and use these resulting scenarios to help decisionmakers understand the vulnerabilities of their plans and assess the options for ameliorating these vulnerabilities. This paper demonstrates the particular value of RDM in helping decisionmakers to design and evaluate adaptive strategies. For IEUA, the RDM analysis suggests the agency's current plan could perform poorly and lead to high shortage and water provisioning costs under conditions of: (1) large declines in precipitation, (2) larger-than-expected impacts of climate change on the availability of imported supplies, and (3) reductions in percolation of precipitation into the region's groundwater basin. Including adaptivity in the current plan eliminates 72% of the high-cost outcomes. Accelerating efforts in expanding the size of one of the agency's groundwater banking programs and implementing its recycling program, while monitoring the region's supply and demand balance and making additional investments in efficiency and storm-water capture if shortages are projected provides one promising robust adaptive strategy — it eliminates more than 80% of the initially-identified high-cost outcomes.  相似文献   

2.
The Ganga Basin, one of the world's most densely populated and vulnerable regions, is also among the world's most dynamic hydrological systems. Rivers exiting the Himalaya deposit massive amounts of sediment in the plains and shift their courses regularly. The natural dynamics of this system have a direct impact on populations. On August 18th, 2008, for example, embankments on the Kosi River (a tributary to the Ganges), failed and the channel shifted by as much as 120 km (Sinha, 2008 [1]) displacing over sixty thousand people in Nepal and three and a half million in India. Transport and power systems disrupted across large areas. The embankment failure was not caused by an extreme event. Instead the breach represented a failure of interlinked physical and institutional infrastructure systems in an area characterized by complex social, political, and environmental relationships.Projected climate changes in the Ganga Basin are likely to greatly exacerbate vulnerability (Adaptation Study Team, 2008 [2]). While the Kosi breach had nothing to do with climate change, such events will increase if climatic variability, sediment transport, and extreme events increase. Understanding how populations can respond to the dynamic nature of rivers such as the Kosi is, as a result, essential to develop strategies for adapting to climatic change. Understanding is also essential at the policy level for building adaptive capacity. The challenge is to identify policy frameworks and their relationship to interlinked physical and institutional infrastructure combinations that create environments enabling adaptation within households, communities, and regions.This paper explores the challenges and opportunities facing the development of adaptive policy frameworks in the Ganga Basin. The characteristics of frameworks that are adaptive in themselves and enable adaptation along with their relationship to different types of interlinked institutional and infrastructure systems are explored first. Following this, the case of the Kosi embankment along with the projected impacts of climate change across the Ganga Basin is used to identify the key challenges and opportunities that are common in many regions. The paper concludes with specific observations on the development of adaptive policy frameworks for responding to climate change in complex developing country contexts.  相似文献   

3.
Frequent droughts and groundwater depletion are critical constraints to improving agricultural productivity in the semi-arid tropics. India has been promoting integrated watershed management in drought-prone areas to address these constraints. Watershed communities are being assisted to invest in groundwater re-charging facilities. While communities and the public bear such costs, individual farmers capture irrigation benefits. Groundwater is a free common property resource and land users hold de-facto use rights. This has accelerated private irrigation investments and depletion of aquifers resulting in iniquitous distribution of irrigation water. Power subsidies and negligible pumping costs aggravate the problem. These policy failures and low irrigation costs to farmers are displacing water-efficient crops in favor of water-intensive crops in water-scare areas. The paper reviews the village-level externalities that aggravate groundwater depletion and evaluates potential policy options to enhance local collective action in water management. Using 3SLS, an econometric crop-water productivity model is used to evaluate alternative water policy instruments. The results indicate that different types of water user charges can be introduced with modest consequences on profitability and farm incomes. If properly implemented and managed by the local communities, pro-poor policies could bring considerable sustainability benefits and also ensure enhanced equity in access to the resource.  相似文献   

4.
The volume of international trade in agricultural commodities is increasing faster than the global volume of production, which is an indicator of growing international dependencies in the area of food supply. Although less obvious, it also implies growing international dependencies in the field of water supply. By importing food, countries also import water in virtual form. The aim of the paper is to assess the water footprints of Morocco, a semi-arid/arid country, and the Netherlands, a humid country. The water footprint of a country is defined as the volume of water used for the production of the goods and services consumed by the inhabitants of the country. The internal water footprint is the volume of water used from domestic water resources; the external water footprint is the volume of water used in other countries to produce goods and services imported and consumed by the inhabitants of the country. The study shows that both Morocco and the Netherlands import more water in virtual form (in the form of water-intensive agricultural commodities) than they export, which makes them dependent on water resources elsewhere in the world. The water footprint calculations show that Morocco depends for 14% on water resources outside its own borders, while the Netherlands depend on foreign water resources for 95%. It is shown that international trade can result in global water saving when a water-intensive commodity is traded from an area where it is produced with high water productivity to an area with lower water productivity. If Morocco had to domestically produce the products that are now imported from the Netherlands, it would require 780 million m3/year. However, the imported products from the Netherlands were actually produced with only 140 million m3/year, which implies a global water saving of 640 million m3/year.  相似文献   

5.
Over the last decades the concepts of Integrated Environmental Assessment (IEA) and Industrial Ecology (IE), both claiming to provide analyses and solutions for sustainability issues, have been developed separately as they emerged in response to questions from different policy-fields. In both fields, specific tools are used to support national and international environmental policy. The focus of IEA and IE tools, however, is different. IEA tools focus on one or a limited number of specific environmental issues. They often model the chain environmental processes with high spatial (and temporal) resolution, but have a low resolution for the material structure of the economy and only partly take into account indirect effects that occur via physical and socio-economic linkages. IE tools take into account all environmental issues related to a specific substance or product. They have a high resolution for the material structure of the economy and take into account indirect effects that occur via physical linkages, however, their environmental modelling is very limited. Both IE and IEA tools have proven to be very useful and neither is superior to the other. However, a combination of both can provide additional information that can be used for more effective policy making. We use the case of a hypothetical world-wide ban on PVC to show that a measure that is not directly related to climate change could still have significant climate effects. This indirect effect is a result of the linkages of material flows in society. We show that IEA tools are not well suited to include these types of effects and that IE tools can fill this gap partially. What is really needed is a broader systems perspective that takes into account the full range of possible side-effects of environmental policy measures.  相似文献   

6.
A payments for ecosystem services (PES) system came about in South Africa with the establishment of the government-funded Working for Water (WfW) programme that clears mountain catchments and riparian zones of invasive alien plants to restore natural fire regimes, the productive potential of land, biodiversity, and hydrological functioning. The success of the programme is largely attributed to it being mainly funded as a poverty-relief initiative, although water users also contribute through their water fees. Nevertheless, as the hydrological benefits have become apparent, water utilities and municipalities have begun to contract WfW to restore catchments that affect their water supplies. This emerging PES system differs from others in that the service providers are previously unemployed individuals that tender for contracts to restore public or private lands, rather than the landowners themselves. The model has since expanded into other types of ecosystem restoration and these have the potential to merge into a general programme of ecosystem service provision within a broader public works programme. There is a strong case for concentrating on the most valuable services provided by ecosystems, such as water supply, carbon sequestration, and fire protection, and using these as ‘umbrella services’ to achieve a range of conservation goals. The future prospects for expansion of PES for hydrological services are further strengthened by the legal requirement that Catchment Management Agencies be established. These authorities will have an incentive to purchase hydrological services through organisations such as WfW so as to be able to supply more water to their users.  相似文献   

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