2. CLM Technical Note

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• 2.1. Introduction
  • 2.1.1. Model History
  • 2.1.2. Biogeophysical and Biogeochemical Processes
• 2.2. Surface Characterization, Vertical Discretization, and Model Input Requirements
  • 2.2.1. Surface Characterization
  • 2.2.2. Vertical Discretization
  • 2.2.3. Model Input Requirements
• 2.3. Surface Albedos
  • 2.3.1. Canopy Radiative Transfer
  • 2.3.2. Ground Albedos
  • 2.3.3. Solar Zenith Angle
• 2.4. Radiative Fluxes
  • 2.4.1. Solar Fluxes
  • 2.4.2. Longwave Fluxes
• 2.5. Momentum, Sensible Heat, and Latent Heat Fluxes
  • 2.5.1. Monin-Obukhov Similarity Theory
  • 2.5.2. Sensible and Latent Heat Fluxes for Non-Vegetated Surfaces
  • 2.5.3. Sensible and Latent Heat Fluxes and Temperature for Vegetated Surfaces
  • 2.5.4. Update of Ground Sensible and Latent Heat Fluxes
  • 2.5.5. Saturation Vapor Pressure
• 2.6. Soil and Snow Temperatures
  • 2.6.1. Numerical Solution
  • 2.6.2. Phase Change
  • 2.6.3. Soil and Snow Thermal Properties
  • 2.6.4. Excess Ground Ice
• 2.7. Hydrology
  • 2.7.1. Canopy Water
  • 2.7.2. Surface Runoff, Surface Water Storage, and Infiltration
  • 2.7.3. Soil Water
  • 2.7.4. Frozen Soils and Perched Water Table
  • 2.7.5. Lateral Sub-surface Runoff
  • 2.7.6. Runoff from glaciers and snow-capped surfaces
• 2.8. Snow Hydrology
  • 2.8.1. Snow Covered Area Fraction
  • 2.8.2. Ice Content
  • 2.8.3. Water Content
  • 2.8.4. Black and organic carbon and mineral dust within snow
  • 2.8.5. Initialization of snow layer
  • 2.8.6. Snow Compaction
  • 2.8.7. Snow Layer Combination and Subdivision
• 2.9. Stomatal Resistance and Photosynthesis
  • 2.9.1. Summary of CLM5.0 updates relative to the CLM4.5
  • 2.9.2. Introduction
  • 2.9.3. Stomatal resistance
  • 2.9.4. Photosynthesis
  • 2.9.5. Canopy scaling
  • 2.9.6. Numerical implementation
• 2.10. Photosynthetic Capacity
  • 2.10.1. Model inputs and parameter estimations
  • 2.10.2. Model structure
  • 2.10.3. Numerical scheme
• 2.11. Plant Hydraulics
  • 2.11.1. Roots
  • 2.11.2. Plant Hydraulic Stress
• 2.12. Lake Model
  • 2.12.1. Vertical Discretization
  • 2.12.2. External Data
  • 2.12.3. Surface Albedo
  • 2.12.4. Surface Fluxes and Surface Temperature
  • 2.12.5. Lake Temperature
  • 2.12.6. Lake Hydrology
• 2.13. Glaciers
  • 2.13.1. Summary of CLM5.0 updates relative to CLM4.5
  • 2.13.2. Overview
  • 2.13.3. Glacier regions and their behaviors
  • 2.13.4. Multiple elevation class scheme
  • 2.13.5. Computation of the surface mass balance
• 2.14. Model for Scale Adaptive River Transport (MOSART)
  • 2.14.1. Overview
  • 2.14.2. Routing Processes
  • 2.14.3. Numerical Solution
  • 2.14.4. Parameters and Input Data
  • 2.14.5. Difference between CLM5.0 and CLM4.5
• 2.15. Urban Model (CLMU)
• 2.16. CN Pools
  • 2.16.1. Introduction
  • 2.16.2. Tissue Stoichiometry
• 2.17. Plant Respiration
  • 2.17.1. Autotrophic Respiration
• 2.18. Fixation and Uptake of Nitrogen (FUN)
  • 2.18.1. Introduction
  • 2.18.2. Boundary conditions of FUN
  • 2.18.3. Resolving N cost across simultaneous uptake streams
  • 2.18.4. Nitrogen Retranslocation
  • 2.18.5. Carbon expenditure on fixation and active uptake.
  • 2.18.6. Modifications to allow variation in C:N ratios
  • 2.18.7. Calculation of N uptake streams from active uptake and fixation
• 2.19. Carbon and Nitrogen Allocation
  • 2.19.1. Introduction
  • 2.19.2. Carbon Allocation for Maintenance Respiration Costs
  • 2.19.3. Carbon and Nitrogen Stoichiometry of New Growth
  • 2.19.4. Carbon Allocation to New Growth
  • 2.19.5. Nitrogen allocation
• 2.20. Vegetation Phenology and Turnover
  • 2.20.1. General Phenology Flux Parameterization
  • 2.20.2. Evergreen Phenology
  • 2.20.3. Seasonal-Deciduous Phenology
  • 2.20.4. Stress-Deciduous Phenology
  • 2.20.5. Litterfall Fluxes Merged to the Column Level
• 2.21. Decomposition
  • 2.21.1. CLM-CN Pool Structure, Rate Constants and Parameters
  • 2.21.2. Century-based Pool Structure, Rate Constants and Parameters
  • 2.21.3. Environmental modifiers on decomposition rate
  • 2.21.4. Management modifiers on decomposition rate
  • 2.21.5. N-limitation of Decomposition Fluxes
  • 2.21.6. N Competition between plant uptake and soil immobilization fluxes
  • 2.21.7. Final Decomposition Fluxes
  • 2.21.8. Vertical Distribution and Transport of Decomposing C and N pools
  • 2.21.9. Model Equilibration and its Acceleration
• 2.22. External Nitrogen Cycle
  • 2.22.1. Summary of CLM5.0 updates relative to CLM4.5
  • 2.22.2. Overview
  • 2.22.3. Atmospheric Nitrogen Deposition
  • 2.22.4. Biological Nitrogen Fixation
  • 2.22.5. Nitrification and Denitrification Losses of Nitrogen
  • 2.22.6. Leaching Losses of Nitrogen
  • 2.22.7. Losses of Nitrogen Due to Fire
• 2.23. Plant Mortality
  • 2.23.1. Mortality Fluxes Leaving Vegetation Pools
  • 2.23.2. Mortality Fluxes Merged to the Column Level
• 2.24. Fire
  • 2.24.1. Non-peat fires outside cropland and tropical closed forest
  • 2.24.2. Agricultural fires
  • 2.24.3. Deforestation fires
  • 2.24.4. Peat fires
  • 2.24.5. Fire trace gas and aerosol emissions
• 2.25. Methane Model
  • 2.25.1. Methane Model Structure and Flow
  • 2.25.2. Governing Mass-Balance Relationship
  • 2.25.3. CH₄ Production
  • 2.25.4. Ebullition
  • 2.25.5. Aerenchyma Transport
  • 2.25.6. CH₄ Oxidation
  • 2.25.7. Reactive Transport Solution
  • 2.25.8. Inundated Fraction Prediction
  • 2.25.9. Seasonal Inundation
• 2.26. Crops and Irrigation
  • 2.26.1. Summary of CLM5.0 updates relative to the CLM4.5
  • 2.26.2. The crop model: cash and bioenergy crops
  • 2.26.3. The irrigation model
• 2.27. Transient Land Use and Land Cover Change
  • 2.27.1. Annual Transient Land Use and Land Cover Data
  • 2.27.2. Reconciling Changes in Area
  • 2.27.3. Mass and Energy Conservation
  • 2.27.4. Annual Transient Land Cover Dataset Development
• 2.28. Dynamic Global Vegetation and FATES
  • 2.28.1. What has changed
  • 2.28.2. FATES
  • 2.28.3. Further reading
• 2.29. Biogenic Volatile Organic Compounds (BVOCs)
• 2.30. Dust Model
• 2.31. Carbon Isotopes
  • 2.31.1. General Form for Calculating ¹³C and ¹⁴C Flux
  • 2.31.2. Isotope Symbols, Units, and Reference Standards
  • 2.31.3. Carbon Isotope Discrimination During Photosynthesis
  • 2.31.4. ¹⁴C radioactive decay and historical atmospheric ¹⁴C and ¹³C concentrations
• 2.32. Land-Only Mode
  • 2.32.1. Anomaly Forcing
• 2.33. References