SERDP Moves into Cold Regions Research
High latitude (cold) regions are on the front line with respect to rapid climate change. The Department of Defense (DoD) also manages large extents of training lands and other assets in cold regions. As a result, SERDP was prompted to take a deeper look into the effects of climate change in these regions. As early as 2011 SERDP initiated funding of three projects that are conducting ongoing investigations on how permafrost (soil and rock that remains below 0°C for two or more years) dynamics are affected by changes in climate and associated changes in vegetation, fire regime, and hydrology in interior Alaska.
Interior Alaska—which contains key DoD training assets—is a region of discontinuous permafrost. For this particular region the temperature at which permafrost thawing and embedded ice melting create unstable ground conditions is close to a tipping point. This has significant implications for DoD’s natural and built infrastructure. As a result, this initial set of research projects was directed at improving our understanding of permafrost behavior and the implications of its changing dynamics under climate change. Based on the early results from these projects and in recognizing that long-term, sustained stewardship of DoD’s natural and built infrastructure in cold regions will be a challenge, SERDP recently created a new sub-area for funded research: Cold Regions Ecology and Management.
Although the sub-area implies a focus on natural resources, SERDP also intends to pursue research in cold regions related to built infrastructure and the effects of climate change. As a result, SERDP began funding a group of research projects in 2014 to improve our understanding and capacity to respond to potential climate change impacts on DoD built infrastructure in Alaska and similar climates. The focus is not only on the implications of changing permafrost dynamics but also on potential changes in snow loads. This latest cohort of projects (described briefly below) will provide models and tools to aid engineers and infrastructure planners with future design of built infrastructure as well as the future operation and maintenance of existing built infrastructure.
The greater warming that has been documented in the Arctic compared to lower latitudes is hypothesized to result in more persistent weather patterns in latitudes south of the Arctic Circle, known as Arctic amplification. Under SERDP project RC-2435, Ms. Kathleen Jones of the U.S. Army Corps of Engineers (USACE)-Cold Regions Research and Engineering Laboratory (CRREL) and her research team are investigating the effect of Arctic amplification on design snow loads for structures in Alaska. More persistent winter weather patterns may result in a greater variation from year to year in the accumulated snow on the ground. For example, preliminary results from an analysis of Snow Telemetry (SNOTEL) data collected by the Natural Resources Conservation Service indicate that the area around Anchorage and a portion of northern Alaska have been experiencing increased variability in the annual maximum snow load. This project will investigate further changing snow load patterns and their implications for roof loading design.
The DoD has five major installations in Alaska and Greenland that are constructed on permafrost. Built infrastructure such as buildings, roadways, and runways, introduce heat to the subsurface, melting the embedded ice and thawing the soil and causing costly settlement. Led by Mr. Kevin Bjella from the USACE-CRREL, SERDP project RC-2436 will determine the best application of borehole drilling, electrical resistivity, and ground-penetrating radar to provide a decision support system to inform planners and engineers on the best pathway to characterizing the status of permafrost. In addition, the project will provide guidance as to the appropriate building foundation to construct based on permafrost condition.
SERDP project RC-2437, led by Dr. Jonathan Ajo-Franklin of the Lawrence Berkeley National Lab and Dr. Anna Wagner of USACE-CRREL, is exploring the use of distributed fiber-optic sensors to monitor the state of permafrost underlying transportation infrastructure, such as roads, runways, and rail lines. The approach combines distributed measurement of temperature and strain as well as seismic waves generated by infrastructure use to infer zones at risk of failure due to climate-induced thaw. This research involves both controlled experiments as well as two field trials in Fairbanks, Alaska and will culminate in a controlled thaw test monitored by the proposed fiber-optic package. Results from this project will potentially provide integration of sensor networks into future infrastructure constructed at high latitudes. Such “smart” installations would have improved reliability in the context of a rapidly changing climate.
For more information, visit SERDP and ESTCP’s Cold Regions Ecology and Management sub-area.