Improved Understanding of Permafrost Controls on Hydrology in Interior Alaska by Integration of Ground-Based Geophysical Permafrost Characterization and Numerical Modeling
RC-2111
Objective
Permafrost distribution in interior Alaska is the primary control on groundwater flow, recharge, and discharge; hence, permafrost influences the number and distribution of surface water bodies, ecosystem state, landscape evolution, and, thus, sustainable infrastructure. For lack of accurate evaluations of permafrost distribution, forecasting changes to Alaskan ecology as a result of climate change or human impacts is currently difficult, if not impossible. Changes in the distribution of wetlands and lakes are occurring and already are widespread in interior Alaska. Efforts are needed to characterize permafrost distribution and develop tools to predict evolving groundwater and permafrost interaction and ecosystem changes driven by climate change.
The objectives of this project are to (1) develop numerical modeling tools to enable prediction of groundwater flow and interaction with permafrost; (2) demonstrate ground-based geophysical methods at several test sites to discover the actual permafrost distribution; and (3) elucidate permafrost-controlled surface water and groundwater interaction at sites within the Yukon River Basin (YRB) by developing models based on field experimental data. These site-specific results will provide a framework to understand the current hydrologic state and to predict hydrologic changes across Alaska.
Technical Approach
The technical approach incorporates computer code development, field experiments, data processing, and modeling. Researchers will extend the U.S. Geological Survey SUTRA code, which currently simulates unsaturated flow, groundwater flow, and heat and solute transport, to incorporate the phase change between ice and liquid water, enabling numerical modeling application to investigate diverse problems critical to designing and ensuring sustainable infrastructure. Well-established geophysical methods will be used to investigate the spatial distribution and thickness of permafrost at several sites that span lacustrine, fluvial, and terrestrial environments. The geophysical results will inform the construction and calibration of site-specific flow and heat-transport numerical models to investigate aquifer/permafrost dynamics and the role of groundwater processes in lake-level declines in the YRB and elsewhere in Alaska. Further, the physics-based understanding developed between site hydrology and permafrost will enable extension of results from the study sites to other regions of Alaska and other permafrost-dominated regions.
Benefits
Results from this project will inform interpretations of the water cycle at many other similar sites in Alaska, enabling climate and human impacts to be distinguished and future impacts to be better predicted. The revised SUTRA model, version 3.0, will provide a critical new tool for the Department of Defense (DoD) and broader community to predict future hydrologic changes and ecosystem consequences associated with different climate change scenarios. The site-specific characterization will directly benefit DoD operations at Fort Wainwright’s Tanana Flats and Donnelly Training Areas where climate warming is resulting in hydrologic and vegetative changes. (Anticipated Project Completion - 2014)
Symposium & Workshop
FY 2013 New Start Project Selections
Points of Contact
Principal Investigator
Dr. Michelle Walvoord
U.S. Geological Survey
Phone: 303-236-4998
Program Manager
Resource Conservation and Climate Change
SERDP and ESTCP
Document Types
- Fact Sheet - Brief project summary with links to related documents and points of contact.
- Final Report - Comprehensive report for every completed SERDP and ESTCP project that contains all technical results.
- Cost & Performance Report - Overview of ESTCP demonstration activities, results, and conclusions, standardized to facilitate implementation decisions.
- Technical Report - Additional interim reports, laboratory reports, demonstration reports, and technology survey reports.
- Guidance - Instructional information on technical topics such as protocols and user’s guides.
- Workshop Report - Summary of workshop discussion and findings.
- Multimedia - On demand videos, animations, and webcasts highlighting featured initiatives or technologies.
- Model/Software - Computer programs and applications available for download.
- Database - Digitally organized collection of data available to search and access.