1. Potential Soil Moisture Retrieval from Aquarius Instrument Mississippi State University Geosystems Research Institute

2. NASA RPC Review (3/2/09) Aquarius Evaluation Team & Collaborators MSU Team –Robert Moorhead –Xingang Fan –Valentine Anantharaj –Georgy Mostovoy –Graduate student (MSU GRI and ECE Dept.) External Team –GMU & CREW Partner Agencies –Garry Schaeffer (USDA NRCS) –Steve Hunter (United States Bureau of Reclamation) 2

3. NASA RPC Review (3/2/09) Our Sponsor: NASA Applied Sciences … NASA's vision is "to improve life here" and our mission is "to understand and protect our home planet". 3

4. NASA RPC Review (3/2/09) Our Sponsor: NASA Applied Sciences … NASA's vision is "to improve life here" and our mission is "to understand and protect our home planet". Applications extend the NASA vision and mission by enabling and facilitating the assimilation of Earth observations and prediction outputs into decision support tools. The purpose is to enhance the performance of the decision support resources to serve society through Earth exploration from space. 4

5. NASA RPC Review (3/2/09) Identified Decision Support Needs Routine analysis land surface state over the continental needs water soils sun weather climate vegetation terrain water soils sun weather climate vegetation terrain observe, model, assimilate 5

6. NASA RPC Review (3/2/09) Anticipated Societal Benefits 1.provides critical information to support drought monitoring and mitigation 2.provides essential information for predicting droughts based on weather and climate predictions 3.supports irrigation water management 4.supports fire risk assessment 5.supports water supply forecasting and NWS flood forecasting 6.supplies a critical missing component to assist with snow, climate and associated hydrometeorological data analysis 7.supports climate change assessment 8.enables water quality monitoring 9.supports a wide variety of natural resource management & research activities such as NASA remote sensing activities of soil moisture and ARS watershed studies. 6

7. NASA RPC Review (3/2/09) Purpose of RPC Aquarius Experiments Evaluate feasibility and usefulness of Aquarius data for decision support in water resources management and other cross- cutting applications. Approach: I.Aquarius Evaluation: Test, characterize, and evaluate potential Aquarius soil moisture data via an OSSE. II.Downscaling for land surface modeling: Downscale Aquarius data and evaluate by land surface modeling. III.Sensitivity Studies: Different LSM(s), input parameters 7

8. NASA RPC Review (3/2/09) Experimental Objectives and Approach Using an OSSE, retrieve potential space-based soil moisture estimation using Aquarius radiometer and scatterometer. Generate moisture and energy fluxes at 10x10 km 2 using a land surface model to assimilate the retrieved synthetic (simulated) soil moisture product. Evaluate experimental products for use in water management applications. Quantify uncertainties. 8

9. NASA RPC Review (3/2/09) Identified Tasks Develop and finalize experimental design. (Otherwise mistake could be expensive to correct). This will particularly include strategies for nature run, emission and backscatter models, orbital and sensor model, selection of retrieval algorithms. Develop and validate nature run. Retrieve soil moisture using the methodology outlined later. Compare with the benchmark data aggregated from the NR. Quantify errors and uncertainties. Document and publish results 9

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14. Aquarius OSSE Design NASA RPC Review (3/2/09) 14

15. NASA RPC Review (3/2/09) Generalized OSSE Framework (Courtesy: JCSDA) 15

16. HYDROS OSSE Example NASA RPC Review (3/2/09) 16

17. NASA RPC Review (3/2/09) 17 Aquarius OSSE: Experimental Design

18. Remote Sensing Concept Radiative Transfer at the surface Soil Surface Vegetation Surface Ts Tb Ts τcτc T1 T3 T2  Tbp can be written as Tbp = T1+T2+T3  T1,T2,T3 correspond to contributions in the above equation  Ts = Soil temperature  Tc = Vegetation temperature  τ c = function of vegetation water content  e sp and r sp are functions of soil water content 18 NASA RPC Review (3/2/09)

19. 1/8 deg domain size: 144x80 points 30.1875 – 40.0625  N, 107.8125 – 89.9375  W If aggregated to 100km: 18x10points 1/8 deg Nature Run using LIS-CLM NASA RPC Review (3/2/09) 19

20. Orbital Senor Modeling Nature Run Forward Modeling Soil Moisture Retrieval NASA RPC Review (3/2/09) 20

21. Nature Run LIS model CLM LSM NLDAS Forcing 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Satellite Obs Orbital model Re-sampling Adding Noise 1 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM CDAS + ENKF 1/8 deg Validation Compare to “truth” OSSE Flowchart (simplified)

22. Nature Run LIS CLM NLDAS Forcing 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM + ENKF 1/8 deg Validation Compare to “truth” Nature Run Output of Soil moisture at 10 soil layers, hourly output from 2002-09-01 to 2003-10-31 1/8 deg resolution Soil moisture of the top layer at 13 UTC 2002-09-01 Nature Run using LIS-CLM

23. Nature Run LIS model CLM LSM 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM + ENKF 1/8 deg Validation Compare to “truth” Forward Emission Output of Brightness Temperature (Tb)as can be seen from radiometer, and radar echo (Sigma) as from back scatterometer, a total of 15 maps each time point: Three look angles (29,38,45) Five variables: two Tb (h,v) and three simga (hh,hv,vv) Tb(h) Tb(v) sigma(hh) sigma(hv) sigma(vv) Shown below are Tb(h), Tb(v), sigma(hh), sigma(hv), sigma(vv) from look angle 29 at 13 UTC 2002-09-01 Forward Modeling Microwave Emissions and Backscatter

24. Orbital Sensor Modeling Simulation of Aquarius Footprints Experiment Domain 30.1875 – 40.0625  N, 107.8125 – 89.9375  W

25. Simulation of Aquarius Footprints RadiometerScatterometer Parameter Inner Beam Middle Beam Outer Beam Inner Beam Middle Beam Outer Beam Look Angle25.833.840.325.933.940.3 Azimuth Angle9.8-15.36.59.7-15.36.5 Footprint Size (km) 89 x 80113 x 88150 x 10668 x 6085 x 67113 x 80 Satellite Tool Kit (STK 8.0) has been used for simulation of Aquarius Footprints Generated geodetic Latitude – Longitude contour line reports for re-sampling with the temperature data Radiometer Footprint Scatterometer Footprint

26. Nature Run LIS model CLM LSM 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Orbital model Satellite Obs Re-sampling Adding Noise 1 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM + ENKF 1/8 deg Validation Compare to “truth” Satellite Tool Kit (STK 8.0) has been used for simulation of Aquarius Footprints Generated geodetic Latitude – Longitude contour line reports for re-sampling with the temperature data Radiometer Footprint Scatterometer Footprint Footprints Inner Beam : 94X76 km Middle Beam: 120X84 km Outer Beam: 156X97 km

27. Nature Run LIS model CLM LSM 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Orbital model Satellite Obs Re-sampling Adding Noise 1 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM + ENKF 1/8 deg Validation Compare to “truth” Look angle 29 Look angle 38 Look angle 45 7-day Tb(h) 7-day Sigma (hh) Look angle 29 Look angle 38 Look angle 45 Noise Gaussian noise of zero-mean and stdev equals 1K and 0.5 dB for Tb and sigma, respectivel y Forward emission model output of Tb and sigma are re- sampled for the Aquarius footprints, and then aggregated to 1-degree resolution. The satellite has a 7- day revisit time period, so the following shows only one Tb and one sigma over a 7-day period, from three look angles.

28. Nature Run LIS model CLM LSM 1/8 deg TOA (Satellite) Emission model Radiometer/ Backscatter 1/8 deg Orbital model Satellite Obs Re-sampling Adding Noise 1 deg Retrieval Inversion model Retrieved soil moisture 1 deg Data assimilation LIS model NOAH LSM + ENKF 1/8 deg Validation Compare to “truth” Average of Tb(h) and Tb(v) retrievals Average of sigma(hh), sigma(hv), and sigma(vv) retrievals Look angle 29 38 45 Retrieved soil moisture [from brightness temperature (Tb) & backscatter (sigma)]

29. Data Assimilation Experiments (Preliminary Results) NASA RPC Review (3/2/09) 29

30. Soil moisture at a lightly-vegetated pixel (34.3125°N, 108.562°W ) NASA RPC Review (3/2/09) 30 Truth Open Loop (No D/A) With Data Assimilation Retrieved SM

31. Soil moisture at a heavily-vegetated pixel (34.3125°N, 94.5625°W ) NASA RPC Review (3/2/09) 31 Truth Open Loop (No D/A) With Data Assimilation Retrieved SM

32. Soil Moisture (domain averaged) NASA RPC Review (3/2/09) 32 Truth Open Loop (No D/A) With Data Assimilation

33. Summary of Progress Completed Tasks –OSSE experimental design –Nature Run (synthetic truth) –Orbital Sensor Modeling and Simulations –Microwave Emissions and Backscatter Modeling –Soil moisture retrieval –Synthesis of experimental SM product –Assimilation of SM product using LIS EnKF (preliminary) Final Steps (in progress) –Validation of DA runs –Error analysis –Final evaluation (document and publish) NASA RPC Review (3/2/09) 33

34. NASA RPC Review (3/2/09) Contact Information Valentine Anantharaj Tel: (662)325-5135vga1@msstate.edu 34