The North American Carbon Program Multi-scale synthesis and Terrestrial Model Intercomparison Project Part 1: Overview and experimental design

Journal Article · Tue Jan 01 00:00:00 EST 2013 · Geoscience Model Development

DOI:https://doi.org/10.5194/gmd-6-2121-2013· OSTI ID:1122662

Huntzinger, D. N. ^[1]; Schwalm, C. ^[1]; Michalak, A. M ^[2]; Schaefer, K. ^[3]; King, A. W. ^[4]; Wei, Y. ^[4]; Jacobson, A. ^[3]; Liu, S. ^[4]; Cook, R. ^[4]; Post, W. M. ^[4]; Berthier, G. ^[5]; Hayes, D. ^[4]; Huang, M. ^[6]; Ito, A. ^[7]; Lei, H. ^[6]; Lu, C. ^[8]; Mao, J. ^[4]; Peng, C. H. ^[9]; Peng, S. ^[5]; Poulter, B. ^[5] ; Riccuito, D. ^[4]; Shi, X. ^[4]; Tian, H. ^[8]; Wang, W. ^[10]; Zeng, N. ^[11]; Zhao, F. ^[11]; Zhu, Q. ^[12]

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1. Northern Arizona University
2. Carnegie Institution for Science, Stanford
3. National Snow and Ice Data Center
4. Oak Ridge National Laboratory (ORNL)
5. Laboratoire des Sciences du Climat et de l'Environnement (LSCE)
6. Pacific Northwest National Laboratory (PNNL)
7. National Institute for Environmental Studies, Tsukuba, Japan
8. International Center for Climate and Global Change Research and School of Forestry and Wildlife Sci.
9. University of Quebec at Montreal, Institute of Environment Sciences
10. National Aeronautics and Space Administration (NASA), Ames Research Center, Moffett Field
11. University of Maryland
12. Laboratory for Ecological Forecasting and Northwest Agriculture and Forestry University

Terrestrial biosphere models (TBMs) have become an integral tool for extrapolating local observations and understanding of land-atmosphere carbon exchange to larger regions. The North American Carbon Program (NACP) Multi-scale synthesis and Terrestrial Model Intercomparison Project (MsTMIP) is a formal model intercomparison and evaluation effort focused on improving the diagnosis and attribution of carbon exchange at regional and global scales. MsTMIP builds upon current and past synthesis activities, and has a unique framework designed to isolate, interpret, and inform understanding of how model structural differences impact estimates of carbon uptake and release. Here we provide an overview of the MsTMIP effort and describe how the MsTMIP experimental design enables the assessment and quantification of TBM structural uncertainty. Model structure refers to the types of processes considered (e.g. nutrient cycling, disturbance, lateral transport of carbon), and how these processes are represented (e.g. photosynthetic formulation, temperature sensitivity, respiration) in the models. By prescribing a common experimental protocol with standard spin-up procedures and driver data sets, we isolate any biases and variability in TBM estimates of regional and global carbon budgets resulting from differences in the models themselves (i.e. model structure) and model-specific parameter values. An initial intercomparison of model structural differences is represented using hierarchical cluster diagrams (a.k.a. dendrograms), which highlight similarities and differences in how models account for carbon cycle, vegetation, energy, and nitrogen cycle dynamics. We show that, despite the standardized protocol used to derive initial conditions, models show a high degree of variation for GPP, total living biomass, and total soil carbon, underscoring the influence of differences in model structure and parameterization on model estimates.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: Work for Others (WFO)
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1122662
• Journal Information: Geoscience Model Development, Vol. 6, Issue 6; ISSN 1991--9603
• Country of Publication: United States
• Language: English