1. DMSP F19 SSMIS Cal/Val Progress and NAVGEM Assimilation Results Tanya Maurer 1, Steve Swadley 1, Gene Poe 2 Ben Ruston 1, Anna Booton 3, Al Uliana 2, Philip Shen 2 1 NRL, Monterey, CA 2 SAIC, Monterey, CA 3 UK Met Office, Exeter, UK 13 th JCSDA Technical Review & Science Workshop College Park, Maryland May 2015

2. Outline Background F19 SSMIS Cal/Val status F19 Cold Bias anomaly detection and mitigation strategy F19 SSMIS assimilation in NAVGEM UPP updates and additions SSMIS Upper Air Sounding (UAS) capabilities SSMIS UPP radiance assimilation impacts Summary and Look Ahead

3. Defense Meteorological Satellite Program (DMSP) heritage: 7 SSM/I, 4 SSMIS Comprehensive Cal/Val program  verify end-to-end instrument performance DMSP & the SSMIS Cal/Val Program Current DMSP MW Imager/Sounder Constellation Status LTAN: Local Time of the Ascending Node DMSP F19 Launched April 3, 2014 SSMIS deployed April 7, 2014 Anomaly & systematic bias detection SDR & EDR validation Algorithm improvements Rapid transition of data & products to users Early Orbit evaluation NEDT analysis Geolocation analysis Scan uniformity analysis

4. SSMIS Special Sensor Microwave Imager/Sounder (SSMIS) 24 channels, 6 feed horns Conical Scan Geometry (53° EIA) Scan Period = 1.89 s (31.6 RPM) Constant Resolution Across Swath Scene integration period = 4.219 msec ChannelsFrequency (GHz) Resolution (Km) Imaging12-1619-3725 Humidity8-11, 17-18 91-18312.5 LAS1-7, 2450-6037.5 UAS19-2360-6375

5. SSMIS Nominal Channel Characteristics Ch. No. Center Frequency [GHz] 1 st IF [MHz] 2 nd IF [MHz] Band Width [MHz] Pol Peak [hPa] Legacy Sensor 150.30. 400.H1000 AMSU-A SSMT-1 252.80. 400.H700 353.5960. 400.H400 454.400. 400.H200 555.500. 400.H100 657.290. 350.CP60 759.40. 250.CP30 8150.01250.0.1500.H AMSU-B MHS SSMT-2 9183.316600.0.1500.H 10183.313000.0.1000.H 11183.311000.0.400.H 1219.350. 400.H SSM/I 1319.350. 400.V 1422.2350. 500.V 1537.00. 1500.H 1637.00. 1500.V 1791.655900.0.1500.V 1891.655900.0.1500.H 1963.283248±285.2710.1.5CP0.02 NEW 2060.792668±357.8920.1.5CP0.05 2160.792668±357.892±2.1.5CP0.7 2260.792668±357.892±5.53.0CP2 2360.792668±357.892±16.8.0CP7AMSU-A 2460.792668±357.892±50.30.0CP15

6. y DMSP SSMIS Radiometric Performance Status NAVGEM 1.2.x Operational Assimilation NAVGEM 1.3 Transition Requires Higher Model Top SSMIS Warm Load NEDTs (NEDT = Noise Equivalent Delta Temperature)

7. F19 SSMIS Cal/Val Progress Geolocation Earth location errors ~20-30 km observed Correction factors derived in terms of along-scan & along-track partial derivatives Errors are reduced to 3-5 km (spec=7km) Environmental Data Records (EDR) Validation OSWS and TPW EDRs validated against ocean buoys and Raob stations New APC coefficients derived Retrieval skill within specification Spec = 2m/s

8. F19 SSMIS Cal/Val Progress Initial NRL RTM Departures Analysis uncovered a Large Cold Bias in the G-band channels. The OB-BK patterns for the 183 GHz channels were similar to F18, but colder by ~8-10K. Only the high frequency G-band channels were affected. Initial focus was on Reflector Roughness, then moved to possibility of FOD in optics via the damaged feedhorn cover. G-Band Cold Bias Investigation

9. F19 SSMIS Cal/Val Progress G-Band Cold Bias Mitigation Histograms Plots of the Observed and Background computed TBs for F19 SSMIS Revs 64-66, 2014040806. Biased histograms are shifted and it was shown that altering the SPOFs would mitigate the cold bias. New SPOFs, α n, derived using ECMWF Analyses and RTTOV-10 computed T BK Computed Ocean Only Scene SPOFs are very stable over time. Original SPOF = 0.9934 F19 Ch. 11 OB and BK Histograms Adjusted SPOF = 0.9587 *SPOF = Spillover Factor

10. F19 SSMIS Cal/Val Progress G-Band Cold Bias Mitigation Method validated through vicarious calibration with F18 Shows good performance across all surface types for 6 month period SPOF modification justified using APC physical model Vicarious Calibration SPOFs match those derived by the NWP RTTOV methodology (within ~0.5-1%) Long Term Averages over Homogenous Surfaces

11. Forecast Model: Navy Global Environmental Model (NAVGEM) – T359L50 – 0.04 hPa model top (~70 km) – ~ 37 km horizontal resolution – Semi-Lagrangian/Semi-Implicit dynamical core, forecast model, explicit clouds DA system: NRL Atmospheric Variational Data Assimilation System – Accelerated Representer (NAVDAS-AR) – T359 outer loop, T119 (~ 111 km) inner loop resolution – Radiance bias correction using variational bias correction approach DMSP F19 SSMIS Data Assimilation 2.6 million obs assimilated every 6 hrs MW radiances provide significant impact to NWP

12. NAVGEM/NAVDAS-AR Operational Data LEO Radiances Imagers/Sounders DMSP F16 SSMIS Imager DMSP F17 SSMIS LAS, UAS, Imager DMSP F18 SSMIS LAS, UAS, Imager DMSP F19 SSMIS LAS, UAS, Imager METOP-A AMSU-A, IASI, MHS METOP-B AMSU-A, IASI, MHS NASA EOS Aqua AIRS, AMSU-A NOAA 15 AMSU-A NOAA 16 AMSU-A NOAA 18 AMSU-A, MHS NOAA 19 AMSU-A, MHS JPSS SNPP ATMS, CrIS, VIIRS GCOM-W1 AMSR-2 Megha-Tropiques MADRAS, SAPHIR MSG Severi MSG-II HIR Jason-1 (SSH, SWH) Jason-2 (SSH, SWH) Cryosat2 (SSH, SWH) GPM GMI Aquarius (Salinity) FY-3A,B,C,D,E,F MWTS,MWHS,MAIRS MERSI FY-RM 1,2 Meteor 3M MTVZA Satellite Winds LEO and GEO Derived Coriolis WindSat Ocean Wind Vector DMSP F16 SSMIS Ocean Wind speed DMSP F17 SSMIS Ocean Wind speed DMSP F18 SSMIS Ocean Wind speed DMSP F19 SSMIS Ocean Wind speed METOP-A AVHRR, ASCAT METOP-B AVHRR, ASCAT NASA EOS Aqua MODIS NASA EOS Terra MODIS, MISR NOAA NPP VIIRS Meteosat 9 Meteosat 10 MTSAT NOAA GOES E NOAA GOES W NOAA GOES-R KMA COMS FY-2E,F,G,H (Geo Winds) FY-4A,B,C (Geo Winds) FY-4A,B,C IR Spectrometer, MW?? GNSS Radio Occultation C/NOFS CORISS COSMIC FM1-6 GRACE-A MetOp-A GRAS MetOp-B GRAS SAC-C TerraSAR-X TanDEM-X COMS Other Satellite Products NASA EOS Aura MLS, HRDLS, OMI NASA TIMED SABER NOAA SBUV JPSS NPP OMPS SMOS SMAP FY-3A,B,C,D,E,F TOU Coriolis WindSat TPW DMSP F16 SSMIS TPW DMSP F17 SSMIS TPW DMSP F18 SSMIS TPW DMSP F19 SSMIS TPW Operational Research Planned Restricted Use

13. Current Operational MW Sensors AMSU-A SSMIS ATMS NAVGEM T359L50 SSMIS Channels assimilated: 2-7, 9-11, 22-24

14. Joint development by NRL and UK Met Office Produces calibrated SSMIS TDR files suitable for radiance assimilation SSMIS UPP V2 Operational at FNMOC (F16 - 07/2008, F17 - 04/2009, F18 - 04/2010, F19 – 10/2014) FNMOC distributes UPP data to NESDIS for use by the global NWP Community Produces ASCII and BUFR TDR output files at full and/or filtered resolution UPP V2 run at FNMOC includes: Reflector Emission Corrections (F16 and F17) NRL-derived SPOF factors for cold-bias mitigation (F19) Operational NGES Fourier Filtered Gain Files to Correct Gain Anomalies Spatial Averaging to reduce NEΔT to 0.15 - 0.25 K level (NRL only) Sensor-specific scan Non-uniformity and Geo-location corrections (corrects for FOV intrusions and spacecraft misalignment) SSMIS Radiance Assimilation by NAVDAS-AR SSMIS Unified Pre-Processor (UPP)

15. F19 UPP data Operational at FNMOC on 14 October 2014 Utilizes NRL SPOF correction methodology for Cold Bias mitigation NRL Assimilating F19 channels 2-7, 9-11, 22-24 averaged at σ=37km Implemented Orbit Angle, φ, calculation for Bias Correction Predictor Testing new orbital bias correction scheme using a Fourier Series in ϕ Developed with Anna Booton (Met Office) during visit (Nov-Dec ‘14) Using reference relative to the position of the sun results in a more stable predictor Ecliptic plane Ascending node φ – angle along the orbital plane β – bias coefficient P – bias predictor ϕ – orbital angle SSMIS UPP Updates and Additions Assimilation of SSMIS by NAVDAS-AR

16. SSMIS UAS UPP Ready for Operations High-peaking SSMIS Upper Atmosphere Sounding (UAS) channels: 19, 20, 21 Affected by Zeeman splitting of the oxygen absorption lines at alt > 50 km, due to interaction of Earth’s magnetic field and SSMIS bore-sight angle Require separate UAS UPP (operates on channels 19-24) Retrievals provide key information about upper atmosphere Includes parameters: mean B mag, B-dot-k, θ B, and std_dev(B-dot-k) within averaging domain (100 closest UAS scenes) Gaussian spatial averaging with σ=75km Orbit Angle, φ, calculation for Bias Correction Predictor Special Met Office file also available at full resolution UAS UPP includes: Calculation of the SSMIS Propagation Vector, k, as the vector difference between the spacecraft and the UAS scene position vectors Extraction of the Geomagnetic field vector, B, components at 60 km * Assimilation of SSMIS UAS channels into NAVGEM is currently limited to CH 21 due to model top

17. Assimilation of SSMIS by NAVDAS-AR SSMIS Radiance Data QC/Prep UPP averaging/thinning: Along-scan Gaussian averaging Every 3 rd scan, every other LAS scene (30 scenes per scan) Every 6 th scan, every other UAS scene (15 scenes per scan) Pre-assimilation thinning: 1.25 ° Quality Control Ocean-only scenes for humidity sounding channels (F18, F19) For temperature sounding channels 02, 03, 04, scenes are rejected if: Surface is not 100% homogenous 20 FOVs in the spatial averaging domain have rain flag set to “true” Jacobian w.r.t. surface temperature exceeds threshold

18. Standard deviations of the bias-corrected innovations (bars) shown on top of weighting functions for each channel. Operational Assimilation Results Temperature Sounding Channels

19. 3 SSMIS UPP (F17,F18,F19) + 4 SSMIS TPW (F16,F17,F18,F19) + 4 SSMIS OSWS (F16,F17,F18,F19) 13.6% of Total Error Reduction 2 IASI 3 SSMIS UPP 6 AMSU-A 3 MHS 1 AQUA/AIRS 5 GEOs 1 WindSat 12 GNSS/GPS Forecast Sensitivity Observation Impact (FSOI)

20. SSMIS F17, F18, F19 UPP Radiances Continue to be the Highest Performing MW Radiances in Total Error Reduction in NAVGEM 2.81 3.41 2.23 0.98 0.96 0.83 0.51 1.99 2.92 2.50 4.33 5.48 1.47 1.21 1.50 1.91 2.42 x 10 -6 Forecast Sensitivity Observation Impact (FSOI) Per Ob Impact

21. Operational Assimilation Results FSOI by channel: F17, F18, F19

22. Summary and Look Ahead 8-10 K cold bias detected in 183 GHz channels  mitigated through modified SPOF in the UPP software Calibrated TDR and UPP data transitioned to operations (10/14) SDRs and Ocean EDRs transitioned to operations (2/15) Implemented Orbital Angle, ϕ, for Bias Correction Predictor in UPP Ready to Transition UPP and UAS-UPP with Orbit Angle Operational performance of F19 SSMIS UPP radiances consistent with suite of high-impact DMSP MW sensors DMSP F20, last of 5 SSMIS sensors, set to launch 2016

23. Thank you

24. Antenna Physical Model To first order APC for G-band, 183 GHz channels (8-11): 1.Feedhorn spill-over loss due to incomplete electromagnetic coupling of feedhorn with reflector 2.Cross-coupling of vertical and horizontal polarizations due to offset parabolic reflector and imperfect feedhorn 3.Field of view intrusion in earth scene sector by spacecraft and/or calibration targets where T A = Antenna temperature (TDR) T S = Scene brightness temperature T C = Cosmic background temperature  = spill-over factor (SPOF) Antenna Pattern Correction (APC) necessary for all SSMIS instruments 24

25. Relate T AF19 to T AF18 on the basis of wide range of TDR “averages” Approach Select diverse regions of the globe with approximate spatial uniformity and relatively small terrain variations Define averages over central portion of swath, separately for both ascending and descending orbits Employ same time period for F19 and F18: April – Sept, 2014 (due to loss of F18 Ch 8, use April – Sept, 2011) From physical model relationship, F19 and F18 TDRs may be defined in terms of a constant slope, a 25

26. Select “a” using: Minimum Mean Square Estimator with Regression through the Origin Approach Knowledge of a implies 26

27. 90% of 10.8 Million total data points assimilated into DoD’s global environmental model (NAVGEM) in a 24 hr period come from satellites 74% of these satellite data points are provided by MW/IR Sounders Satellites from Multiple Agencies, Platforms and Orbit Planes Feed Data to the DoD Models Current NAVGEM: 37km Resolution 50 Vertical Levels IA Compliant Class/Unclass Domains MW and IR Sounders in Multiple Orbit Planes Provide the Majority of the Data Necessary to Drive DoD’s Global Weather Prediction Model NAVGEM Provides Lateral Boundary Conditions for High Resolution Models: COAMPS and COAMPS-TC Class/Unclass Domains

28. NAVGEM Operational Real-time Data Counts 10.8 Million Total OBs per Day Assimilated DTG: 2014121700 Ob TypeSensorOB Count/Day% TotalOB Impact % SatelliteAll9.82x 10 6 90.8859.3 HyperSpec IRIASI(2), AIRS4.80x 10 6 44.4416.5 MW SounderAMSUA(6), ATMS SSMIS(3), MHS(2) GPS-RO 3.19x 10 6 29.5622.8 Feature Tracked Winds GOES(3), Polar(3), MeteoSat(2), GMS, LeoGeo, 1.70x 10 6 15.7723.5 OSWVASCAT(2), WindSat 0.0640x 10 6 0.592.2 MW Imager OSWS, TPW SSMIS, WindSat(TPW) 0.0720x 10 6 0.674.0

29. Upper Atmosphere Sounding Capability Post F20 SSMIS SSMIS - ONLY Operational Satellite with Mesospheric Soundings Most Operational NWP Centers pushing upper model levels to ~100 km NRL-DC/MRY have devoted significant resources in developing Upper Atmosphere NWP capability Operational use of 3 highest peaking channels just now coming into use