Off-line tests of the land surface model NOAH for Alaskan sites

In the land surface model NOAH-LSM (e.g., Mitchell et.al, 2002), frozen soil and snow pack physical processes are included. Briefly, NOAH-LSM allows for temporal variability in snow properties, ice formation within the soil and the effects of soil ice on soil water diffusivity, water potential and thermal conductivity. Fractional snow coverage in a grid cell is allowed to account for the effect of patchy snow on the surface albedo.

Previously, we have coupled the NOAH-LSM model to the Penn State/NCAR MM5 modeling system as an option and investigated coupled simulations of the MM5-LSM system for the Arctic regions.. From the coupled simulation results, we found that it is difficult to evaluate the performance of the NOAH-LSM model thoroughly in the coupled system. Therefore, in this study we perform a series of off-line simulation tests to more thoroughly validate the NOAH-LSM model for Arctic land system simulations.

We apply the model over several Alaskan sites for the off-line tests. The data collected from sites associated with the Arctic Transitions in the Land-Atmosphere System (ATLAS) project, the Caribou Poker Creeks Research Watershed (CPCRW) project and other projects will be used in the validation of model simulations. Results from the simulations will be used to suggest improvements for a version of NOAH-LSM that is optimally suited to Arctic land ecosystems.