U.S. Department of Energy Office of Biological and Environmental Research

BER Research Highlights


Arctic Greening Thaws Permafrost, Boosts Groundwater Flow
Published: October 15, 2018
Posted: April 22, 2019

Models are used to understand how low-Arctic landscapes are changing in a warming climate.

The Science
Models of permafrost dynamics were used to show that snow drifts associated with tall shrub patches warm the underlying soil, resulting in holes called “through taliks” in the permafrost. Through taliks can activate deep flow pathways that significantly alter groundwater flow patterns in shrub-tundra landscapes.

The Impact
The resulting increases in groundwater discharge suggest that observed increases in tall shrub abundance throughout the Arctic may be a driver of observed increases in winter Arctic river discharge.

Summary
At hilly field sites in the southern Seward Peninsula, AK, patches of deep snow in tall shrubs are associated with higher winter ground temperatures. Researchers from the NGEE-Arctic study show that through taliks—thawed zones extending through the entire permafrost layer— can form under these patches. The formation of through taliks creates new hydrologic pathways connecting the near surface to deeper regions, with significant hydrological and biogeochemical consequences. In particular, through taliks enable exchange and transport of nutrients and soil carbon from shallow upland hillslope sources to streams and lakes through groundwater discharge. To better understand the processes controlling and consequences of through taliks, they used NGEE-Arctic’s permafrost hydrology model, ATS, to simulate through taliks associated with snow drifts. Scenarios were developed based on an intensively studied hillslope transect on the southern Seward Peninsula. In these scenarios, when through taliks formed, sub-permafrost groundwater flow greatly increased. The simulations showed that through talik can form quickly (over a few decades) and then drive a rapid increase in sub-permafrost groundwater.

Contacts (BER PM)
Daniel Stover
SC-23.1
Terrestrial Ecosystem Science
Daniel.Stover@science.doe.gov

Elchin Jafarov
Los Alamos National Laboratory
elchin@lanl.gov

Ethan Coon
Oak Ridge National Laboratory
coonet@ornl.gov

Funding
This work is part of the Next Generation Ecosystem Experiments (NGEE) Arctic project which is supported by the Office of Biological and Environmental Research in the DOE Office of Science.

Publications
Jafarov, E.E., E.T. Coon, D.R. Harp, C.J. Wilson, S.L. Painter, A.L. Atchley, & V.E. Romanovsky. “Modeling the role of preferential snow accumulation in through talik development and hillslope groundwater flow in a transitional permafrost landscape.” Environmental Research Letters 13, 105006 (2018). [DOI:10.1088/1748-9326/aadd30]

Related Links
NGEE Arctic

Topic Areas:

  • Research Area: Terrestrial Ecosystem Science
  • Research Area: Next-Generation Ecosystem Experiments (NGEE)

Division: SC-23.1 Climate and Environmental Sciences Division, BER

 

BER supports basic research and scientific user facilities to advance DOE missions in energy and environment. More about BER

Recent Highlights

May 10, 2019
Quantifying Decision Uncertainty in Water Management via a Coupled Agent-Based Model
Considering risk perception can improve the representation of human decision-making processes in age [more...]

May 09, 2019
Projecting Global Urban Area Growth Through 2100 Based on Historical Time Series Data and Future Scenarios
Study provides country-specific urban area growth models and the first dataset on country-level urba [more...]

May 05, 2019
Calibrating Building Energy Demand Models to Refine Long-Term Energy Planning
A new, flexible calibration approach improved model accuracy in capturing year-to-year changes in bu [more...]

May 03, 2019
Calibration and Uncertainty Analysis of Demeter for Better Downscaling of Global Land Use and Land Cover Projections
Researchers improved the Demeter model’s performance by calibrating key parameters and establi [more...]

Apr 22, 2019
Representation of U.S. Warm Temperature Extremes in Global Climate Model Ensembles
Representation of warm temperature events varies considerably among global climate models, which has [more...]

List all highlights (possible long download time)