MsTMIP Simulations

Introduction

The factors that influence the spatial and temporal evolution of carbon sources and sinks vary across the globe. However, the precision, as well as the spatial and temporal resolution, of available driver data varies greatly across regions. Thus, global simulations are needed for comparison with important atmospheric CO2 constraints, while regional simulations will provide the necessary linkage with more well characterized observational datasets. Therefore, participants will be asked to run two sets of simulations at the global and regional scales.

• Global simulations will be at 0.5° by 0.5° resolution and the domain will include all land points, excluding Greenland and Antarctica.
• Regional simulations will be at 0.25° by 0.25° resolution and the domain will include all gridcells that are more than 50% land in North America, excluding Greenland.

Sensitivity Analysis

The ability to partition observed net ecosystem exchange (NEE) among processes such as climate variability, CO2 fertilization, nitrogen limitation, current land management, and the recovery from historical land use and disturbance is fundamental to understanding the terrestrial carbon cycle. Therefore, in combination with the baseline simulations, participating modeling teams are asked to run simulations with (1) recycled climate; (2) land-use and disturbance history; (3) time-varying Atmospheric CO2 concentrations; and (4) time varying nitrogen deposition rates. These sensitivity (Table 2) simulations are required of all modeling teams receiving financial support from the MsTMIP activities, and will help the modeling community to quantify uncertainty associated with reproducing the current state of the terrestrial carbon cycle.

In the sensitivity analysis, we will employ a one-at-a-time (OAT) strategy, where the modeling teams run a series of simulations, changing one input (such as weather) or turning off other internal process (such as nitrogen deposition) in each simulation. The baseline simulations, as described above, will serve as the reference case. All simulations (baseline and sensitivity) should follow the same spin-up procedure.

List of Simulations Required by MsTMIP

References

1. Huntzinger, D.N., et al., (2013) The North American Carbon Program (NACP) Multi-scale Synthesis and Terrestrial Model Intercomparison Project (MsTMIP): Part I - Overview and Experimental Design. Geoscientific Model Development, 6, 2121-2133, doi:10.5194/gmd-6-2121-2013.