CNH: Institutional Dynamics of Adaptation to Climate Change: Longitudinal Analysis of Snowmelt-Dependent Agricultural Systems

全球取水量在过去40年里翻了一番，灌溉农业用地从1.38亿公顷扩大到1961年至2003年期间的2.77亿公顷。灌溉土地占全球消耗性用水的85%以上，仅在全球20%的农田上生产了约45%的全球粮食供应。在农业生产中越来越多地使用灌溉，加上许多农业区融雪的重要性，导致世界上六分之一以上的人口依赖冰川和季节性积雪作为其主要的径流来源。气候变化过程预计将影响全球降雪量和排放的季节性。仅气候变化的温度效应就足以改变许多农业系统的积雪堆积和融雪动态。虽然气候变化对生长季降雨量、径流和干旱的额外影响可能会加剧或缓解融雪气候学对作物可用水的变化，但许多农业系统对融雪和灌溉的依赖可能会降低它们应对未来变化的能力。另一个令人关切的问题是，许多依赖冰川融化的温带和热带农业区现在正面临冰川完全消失的威胁，这使得这些地区的气候变化可能比只将季节性融雪作为水资源的地区更具破坏性。面对水资源短缺，为分配水资源而建立的治理机构可能会被打乱，并被迫改变。气候变化的潜在影响与高度依赖用于农业灌溉的冰川径流的现有和未来用水模式之间存在严重的紧张关系。这一跨学科研究项目将审查人类人口将如何受到这些变化的影响，以及冰川灌溉农业系统用户的适应能力。研究人员将研究依赖融雪的半干旱农业系统，这些系统分布在肯尼亚东部和美国西部形成强烈对比的机构和水文环境中。他们将整合从焦点小组、用水者访谈、实地水文测量、角色扮演游戏和基于情景的潜在气候变化影响模型收集的信息，以评估社区对气候变化的脆弱性，并了解社区可能如何应对未来水资源供应的变化。这些项目将涉及人类行为者之间的相互作用、它们构建和维护的物质和社会资本以及水的可获得性和跨空间规模分配的动态。该项目将对水资源的管理以及社区和家庭如何应对缺水问题产生重大影响。对过去和现在的水治理的经验分析将有助于开发基于情景的潜在气候变化影响模型，以评估社区对气候变化的脆弱性，并了解社区未来可能如何应对水资源供应的变化。该项目的发现将对政策制定者有价值，他们正在寻求更微妙的政策回应，而不是简单的“一刀切”的解决方案。许多政策分析人士建议，一种治理方式，如政府或私人所有制，是应对生态系统威胁的“理想”。这项研究将发展关于机构多样性如何有助于有效管理水资源的新知识。该项目得到了美国自然与人类耦合系统动力学(CNH)计划的支持。

Global withdrawals of water have doubled over the past 40 years as irrigated agricultural land expanded from 138 million ha to 277 million hectares during the period from 1961 to 2003. Irrigated land is responsible for more than 85 percent of global consumptive water use, producing approximately 45 percent of the global food supply on only 20 percent of global cropland. The combination of the increasing use of irrigation in agricultural production and the importance of snowmelt in many agricultural areas has led to a situation where more than one-sixth of the world's population relies on glaciers and seasonal snow packs as their primary source of streamflow. Climate change processes are projected to impact the amount of snowfall and the seasonality of discharge around the globe. Temperature effects of climate change alone will be sufficient to alter both snowpack accumulation and snowmelt dynamics of many agricultural systems. While additional climate change impacts on growing season rainfall, streamflow, and drought could serve to either exacerbate or mitigate shifts in snowmelt climatology on water available for crops, the dependence on snowmelt and irrigation in many agricultural systems may reduce their ability to respond to future changes. Of additional concern is the fact that many temperate and tropical agricultural areas dependent on glacial meltwater are now facing the threat of complete glacier loss, making climate changes in these regions potentially more disruptive than in areas where only seasonal snowmelt is used as a water resource. In the face of water shortages, governance institutions established to allocate water may be disrupted and forced to change. Critical tensions exist between the potential impacts of climate change and existing and future patterns of water use in regions highly dependent on glacier-fed streamflow for agricultural irrigation. This interdisciplinary research project will examine how human populations will be impacted by these changes and the capacity of users in glacier-irrigated agricultural systems to adapt. The investigators will examine semi-arid agricultural systems that are dependent on snowmelt located across strongly contrasting institutional and hydrological settings in eastern Kenya and the western United States. They will integrate information gathered from focus groups, water-user interviews, field hydrological measurements, role-playing games, and scenario-based models of potential climate change impacts to assess community vulnerability to climate variability and understand how communities might respond to changes in water availability in the future. They will address interactions among human actors, the physical and social capital they construct and maintain, and the dynamics of water availability and allocation across spatial scales.This project will have significant implications for the governance of water resources and how communities and households cope with water scarcity. The empirical analysis of past and present water governance will support the development of scenario-based models of potential climate change impacts to assess community vulnerability to climate variability and to understand how communities might respond to changes in water availability in the future. Findings from this project will be of value to policy makers who are seeking more nuanced policy responses than simple "one size fits all" solutions. Many policy analysts recommend one-type of governance, such as government or private ownership, as being "ideal" to cope with threats to ecological systems. This research will develop new knowledge about the ways in which institutional diversity can contribute to the effective management of water resources. This project is supported by the NSF Dynamics of Coupled Natural and Human Systems (CNH) Program.