1. Multiple Non-Uniform Resolution Grid Model 050 km San Pedro River Benson Tombstone USA MEXICO Cananea BLM – SPNRCA Sierra Vista Ft. Huachuca Uniform Resolution 500m 1 km 3 km 9 km.5 km Multiple Uniform Resolutions Multiple Non-Uniform Resolutions Luis A. Bastidas, Norman L. Miller Soni Yatheendradas, Ajay Kalra, Jiming Jin

2. Multiple Non-Uniform Resolution Grid Model 9 km 1 km Preliminary Results Luis A. Bastidas, Norman L. Miller Soni Yatheendradas, Ajay Kalra, Jiming Jin

3. Remote Sensing Influence on Errors 30405060708090100 0 1 2 3 4 5 Ground Temp RMSE [K] Sensible Heat RMSE [w/m²] 30405060708090100 0 1 2 3 4 5 Ground Temp RMSE [K] Latent Heat RMSE [w/m²] 30405060708090100 30 40 50 60 70 80 90 100 Sensible Heat RMSE [w/m²] Latent Heat RMSE [w/m²] Ground Observations P replaced S  replaced P and S  replaced Ground Observations P replaced S  replaced P and S  replaced L. Bastidas, H. Gupta, S. Sorooshian

4. Ongoing PILPS Semi Arid Experiment Lucky Hills Kendall Tucson NEW MEXICO L. Bastidas, H. Gupta, W. Emmerich, B. Nijseen, E. Small SAHRA

5. Ongoing PILPS Science Questions 1.What is the ability of the models to reproduce the water, energy, and carbon exchanges in semi-arid environments? 2.Are the current (usually single) representations of semi-arid lands in the models enough to reproduce the different environments that exist in those areas? 3.Does model calibration reduce the among-model range in the model simulations? 4.How much influence does the model parameterization have on the parameter estimations of “physically meaningful” parameters? 5.Do current carbon representations, developed for forests, properly reproduce carbon exchanges over vegetated arid lands?