RUI: Water from Stone -- Investigating the Hydrologic Role of Rock Glaciers

Middlebury College, Middlebury VT

Investigators

Abstract

Rock glaciers form when ice glaciers are buried by rock avalanches, or when ice accumulates within loose piles of rubble at the base of steep cliffs. In both cases, this ice can deform, allowing the rock glacier to slowly move downhill. When rock glaciers extend to lower, warmer elevations, or when summer temperatures rise, this ice melts and water is released to feed streams and wetlands. This project will investigate how much water is coming out of the hundreds of rock glaciers in two mountain ranges in Utah that are important contributors of water to the Colorado River system, the Uinta Mountains and the La Sal Mountains. Undergraduate students at Middlebury College will be directly involved in all aspects of the field and laboratory research. These students will also participate in mentoring of students at Terra Academy, a public high school in northeastern Utah. Previous work has demonstrated that rock glaciers alter the timing and amount of runoff in high-elevation watersheds and serve as an important component of late summer baseflow. There is also evidence that thawing of permafrost within rock glaciers is releasing meltwater formerly archived as perennial ice. If the ice reservoir within rock glaciers is eliminated, then there may be less water available for these watersheds in the future. This project will test the hypothesis that melting of formerly perennial ice within rock glaciers is contributing unsustainably to the hydrology of high-elevation watersheds. Techniques will include a combination of satellite-based radar interferometry for monitoring rock glacier movement; deployment of dataloggers for recording the temperature of rock glacier surfaces and water discharges; sequential sampling and hydrochemical characterization of rock glacier discharge waters; dating of rock glacier melt water; and ground penetrating radar surveying to identify internal ice. This project will provide numerous opportunities for involvement and training of undergraduate students in cutting-edge research methods. The principal investigators and their students will also mentor high-school students at Terra Academy, a public school in northeastern Utah, who will conduct independent research on hydrology and related topics. Results will be communicated with the US Forest Service to aid management decisions and better predict future changes in water availability. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.