Key Considerations in Linking
Permafrost, Ecosystems and Run-off
Readiness of Existing Models
for Coupling
Land-Atmosphere Water & Energy Cycles
William J. Gutowski, Jr.
Dept. of Geological & Atmospheric Sciences
Iowa State University
Complexity of Arctic terrain
1. A range of “permanent” land surface types
(forest, tundra, wetlands, glaciers)
2. Seasonal variation: snow cover, freeze/thaw of
soil and water bodies
3. Mix of hydrological landscapes
(unorganized flow  major rivers)
Are the fluxes (couplings) well modeled?
Atmosphere
(water availability,
nutrients)
Ecosystems
(snow cover,
albedo)
Surface Water
Permafrost
(ponding,
wet soil)
Issue: Resolution of Observations
Borehole Locations
Issue: Horizontal Resolution of Model
Borehole Locations
~ 0.5˚ grid
Great Bear
Lake
Mackenzie
River
Issue: Vertical Resolution of Model
Active Layer Depth Over Permafrost
(31 stations in Siberia; Frauenfeld et al., 2004)
Issue: Vertical Resolution of Model
Active Layer Depth Over
Permafrost
(31 stations in Siberia;
Frauenfeld et al., 2004)
10 cm
40 cm
100 cm
200 cm
NOAH LSM
(Chen and Dudhia, 2001)
Issue: Standard Landcover Types
1) Broadleaf-evergreen trees
2) Broadleaf-deciduous trees
3) Broadleaf and needleleaf trees
4) Needleleaf-evergreen trees
5) Needleleaf-deciduous trees (larch)
6) Broadleaf trees with groundcover
7) Groundcover only
8) Broadleaf shrubs with groundcover
9) Broadleaf shrubs with bare soil
10) Dwarf trees/shrubs with groundcover (tundra)
11) Bare soil
12) Cultivations
13) Wetland
14) Dry coastal complex
15) Water
16) Glacial
Both specified as
“12) Cultivations”
 Need “Data
Rich” Approach
Sufficient Detail?
Further Challenges to Modeling
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Movement of water and heat in frozen soil
Runoff sensitivity to presence/absence of permafrost
Annual cycle of river ice
Change in landscape structure (e.g., slumping with permafrost
decline)
Change in wetlands (slow, disorganized flow)
Ecosystem evolution as permafrost and runoff change
(dynamic vegetation modeling)
Permafrost evolution as ecosystems change
Question/Comments?