Key Considerations in Linking Permafrost, Ecosystems and Run-off

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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
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Complexity of Arctic terrain

• 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)

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Are the fluxes (couplings) well modeled?
Atmosphere

(water availability, nutrients)
Ecosystems
Surface Water
Permafrost
(snow cover, albedo)
(ponding, wet soil)
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Issue Resolution of Observations
Borehole Locations

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Issue Horizontal Resolution of Model
Borehole Locations
0.5 grid
Great Bear Lake
Mackenzie River
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Issue Vertical Resolution of Model
Active Layer Depth Over Permafrost (31 stations
in Siberia Frauenfeld et al., 2004)
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Issue Vertical Resolution of Model
Active Layer Depth Over Permafrost (31 stations
in Siberia Frauenfeld et al., 2004)
10 cm
40 cm
100 cm
NOAH LSM
200 cm
(Chen and Dudhia, 2001)
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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
Sufficient Detail?
Both specified as 12) Cultivations
? Need Data Rich Approach
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Further Challenges to Modeling

• 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

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Question/Comments?