02/01/2010

Limitations to Modeling Heterogeneous Landscapes in Climate Research

Summary

Characterizing the carbon balance and heat fluxes in heterogeneous landscapes is difficult, yet critical to understand present and future climate-land surface interactions, including ecosystem feedbacks to climatic change. A recent DOE study investigated modeling approaches, using three years of high quality measurements, to characterize land-atmosphere interactions in the very heterogeneous U.S. southern Great Plains. The modeling approach used in current land-surface models led to discrepancies in the regional carbon balance of up to 50% (weekly total) and 20% (annual total). Discrepancies in predicted weekly average regional latent heat fluxes were smaller but also existed for spatial and diurnal predictions. In this heterogeneous system, more rigorous characterization of spatial variation of land surface properties than that used in present models is needed to make accurate regional simulations.

References

Riley WJ, Biraud SC, Torn MS, Fischer ML, Billesbach DP, Berry JA (2009) Regional CO2 and latent heat surface fluxes in the Southern Great Plains: Measurements, modeling, and scaling. J. Geophys. Res. – Biogeosciences 114 Article Number: G04009.