ORCHIDEE

ORCHIDEE is a global process-oriented Terrestrial Biosphere Model [Krinner et al., 2005]. It calculates carbon, water and energy fluxes between land surfaces and the atmosphere. The water and energy component computes major biophysical variables (albedo, roughness height, soil humidity) and solves the energy and hydrological balances at a half-hourly time step. The carbon module describes photosynthesis and respiration at the same temporal resolution; the slow components of the terrestrial carbon cycle (including LAI, carbon allocation in plant reservoirs, soil carbon dynamics, and litter decomposition) are calculated on a daily basis. A turnover rate is applied to biomass pools and produces litterfall. Litter is decomposed and goes into three soil organic carbon pools with different residence times (active, slow and passive) following the CENTURY model [Parton et al., 1988]. The link between the water and carbon modules is done through photosynthesis, which is based on the work of Farquhar et al. [1980] for C3 plants and Collatz et al. [1992] for C4 plants. The stomatal conductance is based on Ball et al. [1987]. The carbon module first calculates LAI and the water and energy module then calculates GPP and stomatal conductance. The carbon module calculates growth and maintenance respirations [Ruimy et al., 1996] and Net Primary Production (NPP), heterotrophic respiration and Net Ecosystem Exchange (NEE). ORCHIDEE is the land surface component of the IPSL-CM5 Earth System Model (Dufresne et al., submitted), currently used for CMIP5 simulations.

The model is joint effort developed by several laboratories. The main developers are:

∗ LMD « Laboratoire des Météorologie Dynamique », CNRS/ENS/Ecole polytechnique/UMPC

∗ LSCE « Laboratoire des Sciences du Climat et de l'Environnement », CEA/CNRS/UVSQ

∗ LGGE « Laboratoire de Glaciologie et Géophysique de l’Environnement », CNRS/Université Joseph Fourier

∗ System Ecology, Amsterdam University

Screen shots

Scientific articles

Krinner, G.; Viovy, N.; de Noblet-Ducoudré, N.; Ogée, J.; Polcher, J.; Friedlingstein, P.; Ciais, P.; Sitch, S.; Prentice, I. C. A dynamic global vegetation model for studies of the coupled atmosphere-biosphere system. Glob. Biogeochem. Cycles 2005, 19 (1).

Piao, S.; Friedlingstein, P.; Ciais, P.; de Noblet-Ducoudré, N.; Labat, D.; Zaehle, S. Changes in climate and land use have a larger direct impact than rising CO2 on global river runoff trends. Proc. Natl. Acad. Sci. U. S. A. 2007, 104 (39), 15242–15247.

Naudts, K.; Chen, Y.; McGrath, M. J.; Ryder, J.; Valade, A.; Otto, J.; Luyssaert, S. Europe’s forest management did not Mitigate Climate Warming. Science (80-. ). 2016, 351 (6273), 597–601.

Technical information

Operating system(s): Linux

Licence: open source

Output(s): Carbon fluxes (respiration, GPP), water fluxes (ETP, …), energy budget.

Other information: The last tag is fully available but the core group doesn’t have the resource to support the users. If interested to collaborate you should contact the core group to have a more formal collaboration on a specific subject (orchidee-projet@listes.ipsl.fr).