Model-data Comparison Highlights Overlooked Processes in Models of Soil Moisture and Hydrology
Date Published
Most models project a long-term drying of the surface soil for the permafrost region despite increases in the net air–surface water flux.
Objective
- Investigate and compare soil moisture projections for eight land models with permafrost processes and highlight the causes and impacts of ground subsidence on soil moisture projections.
New Science
- Models commonly used to represent carbon loss from tundra ecosystems were analyzed, for the first time, to identify assumptions underlying soil moisture calculations.
- Thawing of permafrost can lead to an increase in the hydraulic conductivity of the soil column, thereby enhancing redistribution of water in the soil column.
Impact
- Large discrepancies in projections remain as the current generation of models substantially differ in how they represent soil thermal processes and ground subsidence as a result of permafrost thaw.
- Models must be further evaluated to further quantify the uncertainty associated with these deficiencies.
Image with caption
Image
Schematic of soil water table with and without ground subsidence
Citation(s)
Text
Andresen, CG, DM Lawrence, CJ Wilson, AD McGuire, C Koven, K Schaefer, E Jafarov, S Peng, X Chen, I Gouttevin, E Burke, S Chadburn, D Ji, G Chen, D Hayes, and W Zhang. 2020. Soil moisture and hydrology projections of the permafrost region – a model intercomparison. The Cryosphere, 14:445–459. https://doi.org/10.5194/tc-14-445-2020
Funding
This research was supported by the Director, Office of Science, Office of Biological and Environmental Research of the US Department of Energy under Contract No. DE-AC02-05CH11231 as part of the Next-Generation Ecosystem Experiments (NGEE Arctic) project.
For more information, please contact:
Christian Andresen