Land Surface Scheme in CRCM5 Advanced modules Summary

1. Outline • Land Surface Scheme in CRCM5 • Advanced modules • Summary

2. Overview: Land surface scheme in CRCM Canadian LAnd Surface Scheme; Verseghy, 1991; Verseghy et al., 1993 Verseghy, 2000 • Thermally separate vegetation canopy, snow cover and three soil layers (0.1, 0.25, 3.75m). • Four main vegetation structural types identified (needleleaf trees, broadleaf trees, crops and grass) • Up to four subareas allowed for land surface type: vegetation covered, bare soil, snow with vegetation and snow over bare soil • One soil type for each grid cell

3. Enhanced features • Option for deeper soil configuration • Ability to model organic soils • Optional mosaic formulation • Ability to model lateral movement of soil water • Enhanced snow density and snow interception

4. http://www.amap.no/acia/Highlights.pdf Drunken forest in Siberia Recent interest in permafrost • Permafrost degradation can have adverse impacts on socio-economic and eco-environmental systems • Climate model projections indicate a rise in the global average temperatures over the next century (IPCC, 2007)

5. 0 – 9 m 1961-1990 Sushama et al. (2006) Simulated average ALT for current and future climates 0 – 6 m 2041-2070 Permafrost (offline) Modelling Drawback: Cannot capture the land/atmosphere feedbacks Can a climate model with a shallow LSS be used to model ALT and near surface permafrost?

6. Infinite half space 3m thick slab with zero flux boundary condition Can a climate model with a shallow LSS be used to model ALT and near surface permafrost? Smerdon and Stieglitz (2006; GRL) Lawrence et al. (2008) Nicolsky et al. (2007) Alexeev et al. (2007)

7. CRCM experiment with shallow and deep Soil Layers 3 layers 13 layers (all 13 layers) 0.10 m 0.10 m 0.25 m 2.5 m 0.35 m 6.0 m 4.0 m 10.0 m 6.0 m 16.0 m 8.0 m 24.0 m 13.0 m 3.75 m 37.0 m 22.0 m Max. depth to bedrock 59.0 m 4.10 m 4.10 m 36.0 m Bedrock: 0.10 m – 3.60 m 95.0 m 95.0 m

8. CRCM experiment with shallow and deep Soil Layers • Soil Initial conditions • Stevens et al. (2008) • forward modelled the ECHO-g simulated, millenial, paleoclimatic histories to obtain the sub-surface thermal profiles, which were validated over North-America, against available borehole measurements • The above forward modelling was done for the period 1000-1990 and the profiles from 1961 were used as initial conditions for the experiments with the deeper version of CLASS3.4

9. Seasonal means, 3 layer run – 13 layer run 1st layer soil temperature Sensible Heat Flux 2 meter temperature W/m² °C °C JJA 1979-2002 different scales! W/m² °C °C DJF 1978-2001 Source: Katja Winger

10. Organic soil Distribution of organic soil Organic soil has higher porosity and hydraulic conductivity compared to mineral soils

11. Organic soil Region with organic soil Inclusion of the organic soil parameterization leads to much cooler temperatures Simulated annual-mean temperature for the top soil layer 3-layer: No organic soil 3-layer: with organic soil Source: Yanjun Jiao

12. Other Modules in CRCM5 (multitude of surface types) • Lakes • Hostetler and Flake models being implemented The Lake Model Intercomparison Project (LakeMIP): http://www.unige.ch/climate/lakemip/index.html

13. Dynamic vegetation Other Modules in CRCM5 Canadian Terrestrial Ecosystem Model (Arora, 2003) • Photosynthesis • Autotrophic respiration • Heterotrophic respiration • Phenology • Turn over of live veg, • Mortality • Allocation • Disturbance due to fire, • Land use related carbon emissions

14. River-Lake system model Routing models: WATRoute Variable velocity (Arora and Boer, 1999; Lucas-Picher, 2003) Variable lag (Sushama et al., 2004)

15. Summary • CLASS: LSS in the Canadian RCM • Features required for high-latitude regions • Upcoming modules • Opportunities to test/share/use modules • Yet to come …. Thermokarst, glaciers, icesheets, ……