Progress in the Joint OSSE System

1. Progress in the Joint OSSE System Lars Peter Riishojgaard and Michiko Masutani JCSDA LWG Meeting, Bar Harbor, 06/01/2010

2. Joint OSSE Team NCEP: Michiko Masutani, Jack Woollen, Yucheng Song, Steve Lord ECMWF: Erik Andersson KNMI: Ad Stoffelen, Gert-Jan Marseille JCSDA: Lars Peter Riishojgaard, Lidia Cucurull, Zaizhong Ma NESDIS: Fuzhong Weng, Tong Zhu, Haibing Sun, SWA: Dave Emmitt, Sid Wood, Steve Greco NASA/GFSC: Ron Errico, Runhua Yang, Will McCarty, Emily Liu, Michele Rienecker, Ron Gelaro NOAA/ESRL:Yuanfu Xie, Nikki Prive, Steve Weygandt NOAA OSSE Testbed initiative (USWRP Executive Committee): Bob Atlas, Steve Koch, … LWG Meeting, Bar Harbor, 06/01/2010

3. Role of a National OSSE Capability • Impact assessment for future missions • Decadal Survey and other science and/or technology demonstration missions (NASA) • Future operational systems (NOAA) • Objective way of establishing scientifically sound and technically realistic user requirements for observing systems • Tool for assessing performance impact of engineering decisions made throughout the development phases of a space program or system • Preparation/early learning pre-launch tool for assimilation users of data from new sensors LWG Meeting, Bar Harbor, 06/01/2010

4. Main OSSE components • Data assimilation system(s) • NCEP/EMC GFS • NASA/GMAO GEOS-5 • NCAR WRF-VAR • Nature run • ECMWF • Plans for embedded WRF Regional NR • Simulated observations, including calibrated errors • Reference observations • Perturbation (“candidate”) observations • Diagnostics capability • “Classical” OSE skill metrics • Adjoint sensitivity studies LWG Meeting, Bar Harbor, 06/01/2010

5. ECMWF Nature Run (Erik Andersson) • Based on recommendations/requirements from JCSDA, NCEP, GMAO, GLA, SIVO, SWA, NESDIS, ESRL • “Low Resolution” Nature Run • Free-running T511 L91 w. 3-hourly dumps • May 12 2005 through June 1 2006 • (Two “High Resolution” periods of 35 days each • Hurricane season: Starting at 12z September 27,2005, • Convective precipitation over CONUS: starting at 12Z April 10, 2006 • T799 L91 levecondition ls, one-hourly dump) • High resolution period abandoned due to poor validation results LWG Meeting, Bar Harbor, 06/01/2010

6. Nature Run validation • Purpose is to ensure that pertinent aspects of meteorology are represented adequately in NR • Contributions from Emmitt, Errico, Masutani, Prive, Reale, Terry, Tompkins and many others • Clouds • Precipitation • Extratropical cyclones (tracks, cyclogenesis, cyclolosis) • Tropical cyclones (tracks, intensity) • Mean wind fields • …. LWG Meeting, Bar Harbor, 06/01/2010

7. Simulation of observations (I), conventional • Conventional observations: “anything other than satellite radiances” • Conceptually simple: Resample NR at observation locations and add error • Problem: For many observation types the locations depend on the atmospheric state: • Radiosondes (drift) • Satellite winds (tracking targets) • Aircraft obs (flight routing) • Ocean surface winds (thresholds and precip) • This is NOT accounted for currently: Actual historical obs locations for 2005 are used • SWA working on more sophisticated approach to scatterometer winds and satellite AMVs • Two approaches so far: • J. Woollen (NCEP), R. Errico (GMAO) LWG Meeting, Bar Harbor, 06/01/2010

8. Observation simulation (II): Radiances • Satellite radiances dominate both in terms of numbers and of impact • Conceptually: Forward radiative transfer applied to NR input profiles • Problem areas: • Treatment of clouds has substantial impact on availability and quality of observations, and on subsequent QC, thinning and ultimately assimilation results • Desire to avoid “identical twin” Radiative Transfer Models; conceptually one should be use one RTM for simulation and a different RTM for assimilation • NOT yet implemented in Joint OSSE • Two different approaches: • H. Sun (NESDIS), R. Errico (GMAO) LWG Meeting, Bar Harbor, 06/01/2010

9. Radiance simulation steps (NESDIS/NCEP) • Template data (in initial version, footprints used for operational data assimilation in the real year 2005 were used) • DBL91 (Nature Run data at footprints to be simulated) • 91 level 3-D data (12 Variables) • 2-D data (71 Variables) • Climatological data • All information to simulate Radiances  • Simulated radiance data saved in ASCII or unpacked format. • Radiance data to packed to WMO BUFR format, using information from template data. LWG Meeting, Bar Harbor, 06/01/2010

11. Calibration for Joint OSSEs at NASA/GMAO Latest version Version 1 REAL OSSE Version 2 REAL OSSE Calibration using adjoint technique Version 1 • Overall impact of simulated data seems realistic • Tuning parameter for cloud clearing • Surface emissivity • Improved simulation of AMVs LWG Meeting, Bar Harbor, 06/01/2010 (Early results; courtesy of Ron Errico)

12. Current status • Joint OSSE collaboration continues to show progress • Extensive validation effort completed successfully • Calibration experiments performed by GMAO, NCEP and ESRL • Reference observing system simulation complete for initial experimental period (July-August 2005) • Wind Lidar project entering year 3 • Ready for initial impact experiments (Michiko’s talk next) • Preliminary simulated lidar winds available from SWA • New post-doc on board (Zaizhong Ma) • Issues: • The effort remains only partially funded • Coordination • Relationship with NOAA’s OSSE testbed initiative still needs to be clarified LWG Meeting, Bar Harbor, 06/01/2010