1. COSMOS Soil Moisture and Water Vapor and Carbon Dioxide Fluxes Russell Scott

2. SECA consists of an array of eddy covariance towers placed throughout southern Arizona to address a number of issues related the functioning of ecosystems in semiarid areas. Creosote Shrubland Grassland Riparian Woodland Savanna Grassland Riparian Grassland and Shrubland

3. Walnut Gulch Experimental Watershed

5. How do interannual and intra-annual variations on precipitation affects H 2 O and CO 2 exchange in semiarid ecosystems 1.Cosmos and TDR soil moisture 2.Cosmos and ET 3.Cosmos and CO2 flux

6. Site Layout KN? TDR profiles, Watershed Flume Cosmos, Metflux, Phenocam

7. Flux sites

8. From TDR profiles B horizon clays inhibit deep infiltration

9. 0-5 cm10 cm15 cm0-10 cm0-18 cm0-25 cm R2R2 0.88 0.600.910.900.86

10. Evaporation Faster decay when plants inactive slower decay when plants active 7 mm runoff

11. Not ActiveActive ETET/EtoETET/Eto R2R2 0.35 0.580.74 Active plants

12. Carbon dioxide flux release uptake

13. Ecosystem respiration and photosynthesis

14. These thresholds are really important for modeling but more information relative to shallow or deep moisture is critical

15. R 2 =0.68 Soil respiration

16. Conclusions Needs Effective depth seems too deep Modeled disaggregated products needed (very shallow and deep soil moisture) from assimilation of COSMOS data into soil moisture models Good news Cosmos provides soil moisture at a spatial resolution commensurate with EC fluxes Preliminary comparisons show that Cosmos data is highly complementary to understanding water and CO 2 fluxes