(1) MODEL AND VERSION:
Full model name: SiB 2 / carbon cycle (Simple Biopshere Model varion 2 including a carbon cycle)
Host institution: Carnegie Institution of Washington, Department of Plant Biology
Key references:
Sellers, J. P., D.A. Randell, G.J. Collatz, J.A. Berry, C.B. Field, D.A. Dazlich, C. Zhang, G.D. Collelo and L. Bounua, 1996. A revised land surface parametrization (SiB 2) for atmospheric GCMs. Part I:Model formulation, J. Climate, 9, 676-705.
Sellers, J. P., S.O. Los, C.J. Tucker, C.O. Justice, D.A. Dazlich, G.J. Collatz and D.A. Randell, 1996. A revised land surface parametrization (SiB 2) for atmospheric GCMs. Part II: The generation of global fields of terrestrial biphysical parameters from satellite data, J. Climate, 9, 706-737.
Potter C.S., Randerson J.T., Field C.B., Matson P.A., Vitousek P.M., Mooney H.A.,
Klooster S.A., 1993. Terrestrial ecosystem production: a process model-based on global satellite and surface data. Global Biogeochemical Cycles, 7, 4, 811-841.
Field C.B., Randerson J.T., Malmstrom C.M., 1995. Global net primary production : combining ecology and remote-sensing. Remote Sensing of Environment, 51, 1, 74-88.
Kaduk, J. and M. Heimann, 1996.Assessing the climate sensitivity of the global terrestrial carbon cycle model SILVAN. Physics and Chemistry of the Earth 21, 5-6, 529-535.
(2) MODEL TYPE (E.G. ECOSYSTEM, BIOGEOGRAPHY, DGVM):
Ecosystem
(3) PRIMARY MODEL PURPOSE:
Diurnal to centennial simulations of water, energy and carbon exchange fluxes between biosphere and atmosphere considering variable climate and atmospheric CO2 concentration.
Land surface simulation for AGCMs
(4) MODELING APPROACH:
Process orientated, climate dependent, using prescribed PAR absorption and LAI from NDVI data.
(5) RESOLUTION (SPATIAL, TEMPORAL):
1 degree, 10 min standard, adjustable
(6) SPATIAL AND TEMPORAL SCALE(S) AT WHICH THE MODEL RESULTS SHOULD BE CONSIDERED:
1 degree, temporal scale should depend on input data, typically 30 min. to daily
(7) PROCESSES AND PROCESS COMPONENTS SIMULATED (E.G. CARBON: GPP, NPP, NEP):
Carbon:
GPP, photo, maintenance and growth respiration, NPP, growth rates, carbon allocation to leaves, fine roots and wood, sapwood, LAI, PAR absorption, litter production, litter and SOC transfer and decay, NEP
Water:
a) Soils (simple bucket, saturated/unsaturated flow, controls on water movement through the profile, etc.): 3 layer soil water, saturated/unsaturated flow controlled by soil texture, temperature and soil water content.
b) Energy balance: (e.g. latent, sensible heat, aet, pet): latent and sensible heat fluxes from canopy and soil, soil heat flux.
c) Snow: one snow layer
d) 'Order' of water balance: (e.g. incoming water is first evaporated from plant/soil surface, then infiltration, transpiration, runoff): plant/litter skin layer evaporation, transpiration, infiltration and water transfer rates, then infiltration, water movement and run-off are determined simultaneously by an implicit backward scheme.
Nitrogen: not simulated
(8) SIMULATED RESERVOIRS:
Carbon:
a) Vegetation: 5 vegetation reservoirs: assimilate, leaves, fine roots, stems and coarse roots
b) Litter: 18 in total: aboveground and belowground (5 soil temperature layer) metabolic and structural herbaceous and woody litter, surface and soil (5 soil temperature layer) microbial biomass
c) SOC: 2 SOC reservoirs in 5 soil temperature layers, 10 in total
Nitrogen:
a) Vegetation: n.a.
b) Litter: n.a.
c) SON: n.a.
Soil water: 3 layer soil water model
(9) CALIBRATION VARIABLE(S) AND METHOD:
Biome mean annual NPP calibrated to observational data and a prescribed hierachy of biome productivity. Adjustment of maximal net photosynthetic rate, minimal, maximal and optimal temperatures for photosynthesis under consideration of a prescribed hierachy of rates and temperatures and rates for the biomes.
(10) SCALING OF THE PROCESSES TO THE GRID CELL:
Multiplication with grid cell area
(11) DISTURBANCE (FIRE, GRAZING, HARVEST, TREE REMOVAL, ETC.):
Large scale natural disturbance parametrized, turnover time of living woody biomass adjusted.
(12) VEGETATION I/O (E.G. POTENTIAL, ACTUAL):
actual, 12 types derived from NVDI
(13) INPUT DRIVERS (CLIMATIC, SITE, VEG, SOILS) AND RESOLUTION (E.G. DAILY, MONTHLY) REQUIRED FOR MODEL INITIALIZATION:
Diurnal data of temperature, precipitation, wind speed, short wave, long wave radiation, water vapor pressure deficit
NDVI, canopy height, LAI, fraction of green leaves, canopy roughness
Soil texture
Vegetation type
(14) ADDITIONAL COMMENTS: