160 likes | 266 Views
CABLE: the Australian community land surface model. Bernard Pak, Yingping Wang, Eva Kowalczyk CSIRO Marine and Atmospheric Research OzFlux08, Adelaide, 4-6 Feb 2008. Australian Community Climate Earth System Simulator (ACCESS) modelling program. Diagram to right shows ‘scope’
E N D
CABLE: the Australian community land surface model Bernard Pak, Yingping Wang, Eva Kowalczyk CSIRO Marine and Atmospheric Research OzFlux08, Adelaide, 4-6 Feb 2008
Australian Community Climate Earth System Simulator (ACCESS) modelling program • Diagram to right shows ‘scope’ • Fundamentally conceived as a modelling ‘system’ that meets a variety of needs. • Priority needs are: • Numerical weather prediction • Climate change simulation capability • Collaboration between key institutions (Bureau, CSIRO, Australian Universities,….)
The general structure of CABLE SEB & fluxes; for soil-vegetation system: Ef , Hf , Eg , Hg; evapotranspiration Canopy radiation; sunlit & shaded visible & near infra-red, albedo Carbon fluxes; GPP, NPP,NEP stomata transp. & photosynthesis Interface to the GCM soil temp. soil moisture soil respiration snow carbon pools; allocation & flow CASA-CNP vegetation dynamics/disturbance Kowalczyk et al., CMAR Research Paper 013, 2006
Vegetation parameters required for CABLE • VEGETATION TYPE • 1 broad-leaf evergreeen trees • 2 broad-leaf deciduous trees • 3 broad-leaf and needle-leaf trees • 4 needle-leaf evergreen trees • 5 needle-leaf deciduous trees • 6 broad-leaf trees with ground cover /short-vegetation/C4 grass (savanna) • 7 perennial grasslands • 8 broad-leaf shrubs with grassland • 9 broad-leaf shrubs with bare soil • 10 tundra • 11 bare soil and desert • agricultural/c3 grassland • 13 ice Geographically explicit data LAI – leaf area index fractional cover C3/C4 - fraction themodel calculates: z0 – roughness length α – canopy albedo A grouping of species that show close similarities in their response to environmental control have common properties such as: - vegetation height - root distribution - max carboxylation rate - leaf dimension and angle, sheltering factor, - leaf interception capacity
Soil parameters required for CABLE Soil Properties: - water balance: wilting point field capacity saturation point hydraulic conductivity at saturation matric potential at saturation - heat storage: albedo, specific heat, thermal conductivity density - soil depth Soil types: Coarse sand/Loamy sand Medium clay loam/silty clay loam/silt loam Fine clay Coarse-medium sandy loam/loam Coarse-fine sandy clay Medium-fine silty clay Coarse-medium-fine sandy clay loam Organic peat Permanent ice Post, W., and L. Zobler, 2000 Global Soil Types
Nonlinear parameter estimation • 19 FLUXNET sites, including all major veg types in the temperate and subtropical climate; • Uniform parameter range ; • Optimisation was applied to each year’s measurements separately; • Each type of obs was weighted by the SD of measurements over a year. • Published in Wang et al. (Global Change Biology, 2001 and 2007)
Relative Vcmax: deciduous forests Leaf growth Leaf fall
Changes to-date • Major clean-up and rewriting of codes in FORTRAN90 standard, making it more modular and more flexible. • A secured website has been set up for code distribution, installation help and exchange of ideas. • Standard scripts introduced to help analyzing results. • Monthly meeting
Future changes • CASA-CNP: Nitrogen and phosphorus have been found to impact strongly on climate predictions. Such nutrient cycles will be implemented within the current year. It also necessitates a better phenology module. • Dynamic vegetation: a UNSW post-doc (Dr. Jiafu Mao) have just started in January. He will implement LPJ into CABLE. • Hydrology: MU and BoM have done some work, we will have at least one post-doc later this year.
CABLE as the Australian community land surface model • Source codes and documentation are available to all registered users online at https://teams.csiro.au/sites/cable/default.aspx(email bernard.pak@csiro.au to register) • We are looking for collaboration to validate/improve CABLE
Observed and estimated vcmax per unit leaf area during growing season (mmol m-2 s-1)