Threshold hydrologic change across the intermittent-persistent snow transition

间歇性-持续积雪过渡期间的阈值水文变化

• 批准号: 1446870
• 负责人: Stephanie Kampf
• 金额: $ 26.81万
• 依托单位: Colorado State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-03-01 至 2020-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1446870&HistoricalAwards=false
• 关键词: Threshold; hydrologic; change; across; intermittent

This project will develop a geographic synthesis of snow, streamflow, and soil moisture data across the western U.S. and the analyses will provide key information that can be used to identify areas most vulnerable to large hydrologic changes due to smaller snowpack accumulation. Datasets produced will be publicly available and this information can be incorporated into land and aquatic resource management, particularly in locations that lack hydrologic data. The project will train a PhD student and undergraduate research assistants, develop an interactive digital display for education outreach and student recruitment, and develop a hydrology class activity using soil moisture simulations. Loss of persistent winter snowpack impacts water resources in mountain and high latitude regions throughout the world, and the need to understand water resource vulnerability to snow loss is pressing. The central hypothesis guiding this research is that loss of a persistent snowpack triggers changes in both stream flow and soil moisture, but the magnitude of this change is greater in more arid climates. This project will document the geographic distribution of intermittent-persistent snow transitions in the western U.S. and examine how streamflow and soil moisture are affected by these transitions. Snow transitions will be mapped using both MODIS snow cover imagery and snow water equivalent data from SNOTEL sites. Indices of snow transitions will then be compared to streamflow and soil moisture data at both annual-decadal time scales and event-seasonal time scales. HYDRUS-1D simulations of soil moisture changes in response to varying scenarios of snow persistence will be developed for SNOTEL sites in two different climate regions to examine how process interactions between snow loss and hydrologic response vary with climate. The study synthesizes a top-down approach examining runoff and soil moisture changes across geographic gradients of snow persistence with a bottom-up process modeling approach examining how soil moisture responds to a transition from persistent to intermittent snow. The multi-scale approach will help in understanding how regional long-term patterns link with local conditions in individual seasons.

该项目将在美国西部开发雪，流量和土壤水分数据的地理综合，分析将提供关键信息，这些信息可用于确定由于较小的积雪堆积而遭受大型水文变化的区域。 生产的数据集将公开可用，并且可以将这些信息纳入土地和水上资源管理中，尤其是在缺乏水文数据的位置。该项目将培训博士生和本科研究助理，开发用于教育外展和学生招聘的交互式数字显示，并使用土壤水分模拟开发水文学课程。 失去持续的冬天积雪会影响世界各地的山区和高纬度地区的水资源，并且需要了解水资源易受雪流失的需求。指导这项研究的中心假设是，持续的积雪的丧失触发了河流和土壤水分的变化，但是在更干旱的气候下，这种变化的幅度更大。该项目将记录美国西部间歇性降雪过渡的地理分布，并检查流量和土壤水分如何受这些过渡的影响。雪过渡将使用MODIS雪图像和Snotel站点的雪水等效数据进行映射。然后，将在年度时间尺度和事件季节时间尺度上将雪过渡的指标与水流和土壤水分数据进行比较。在两个不同气候区域中的Snotel地点将开发对土壤水分变化的水力1D模拟，以响应不同的雪持续状态，以研究雪流失和水文反应之间的过程相互作用如何随气候而变化。该研究综合了一种自上而下的方法，研究了径流和土壤水分的变化，从雪持续的地理梯度进行了自下而上的过程建模方法，研究了土壤水分如何响应从持续到间歇性雪的过渡。多尺度方法将有助于理解区域长期模式如何与各个季节的当地情况联系在一起。