Unfrozen Permafrost Presence in Shrub-Dominated Landscapes

Field observations and model simulations confirm the presence of unfrozen permafrost in shrub-dominated landscapes.

November 27th, 2019
The Science: 
  • Shrubs, especially tall shrubs, trap snow and provide an insulating layer that keeps ground warmer than the surrounding landscape.
  • Increases in groundwater discharge due to talik formation can contribute to the observed increases in Arctic river discharge during the winter and spring snowmelt period.
The Impact: 
  • Numerical experiments explain that the transition from continuous to discontinuous permafrost can happen quickly, and create new pathways for water flow in hillslope environments.
Summary: 
  • The authors aimed to couple surface and subsurface thermal-hydrology in permafrost landscapes and simulate the timing and magnitude of talik formation associated with shrubs and snow.

 

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

Schematic of modeling transect showing simulated formation of talik (e.g., unfrozen soil) beneath shrubs that capture snow, and hence influence ground thermal regime during the winter. All parameters for model simulations were obtained from data collected

Contacts: 

Elchin E Jafarov
Los Alamos National Laboratory