1 Need for collaboration in OSSEs December 2009 Michiko Masutani

2  Data impact on analysis and forecast will be evaluated.  A Full OSSE can provide detailed quantitative evaluations of the configuration of observing systems.  A Full OSSE can use an existing operational system and help the development of an operational system. Full OSSE Advantages Existing Data assimilation system and velification method are used for Full OSSEs. This will help development of DAS and verification tools.

3 Real data OSE Observing System Experiment –Typically aimed at assessing the impact of a given existing data type on a system –Using existing observational data and operational analyses, the candidate data are either added to withheld from the forecast system, and the impact is assessed –Control run (all operationally used observations) –Perturbation run (control plus candidate data) –Compare! Simulated data (OSSE) Observing System Simulation Experiment Typically aimed at assessing the impact of a hypothetical data type on a forecast system Simulated atmosphere (“Nature Run”) Simulated reference observations (corresponding to existing observations) Simulate perturbation observations (object of study) Verify simulated observation Simulate observational error Control run (all operationally used observations) Perturbation run (control plus candidate data) Compare! Costly in terms of computing and manpower Data Denial Experiments

4 Comments on OSSE Calibration ●OSSE funding should include simulation of calibration data and calibration of OSSE. OSSE funding tend to expect that OSSE system already exists. ● Calibration and simulation of basic observation effort has to be done sharing OSSE resources. ● Without calibration, quantitative evaluation data impact using OSSE could mislead the meteorological community. In this OSSE, calibration was performed and presented.

Experience from the past In 1993, ECMWF produced Nature Run in T213. Observations are simulated while the NR was produced The data were distributed with significant cost Problems Radiance data was not simulated correctly and cannot be used. SST was kept constant and that affect the OSSE results. Took long time to find fund to conduct OSSEs NOAA simulated observation including radiance data and conduct OSSEs to evaluation DWL. Masutani, M., J. S. Woollen, S. J. Lord, G. D. Emmitt, T. J. Kleespies, S. A. Wood, S. Greco, H. Sun, J. Terry, V. Kapoor, R. Treadon, and K. A. Campana, Observing System Simulation Experiments at the National Centers for Environmental Prediction. J. Geophys. Res., 114, doi: /2009JD Results were mainly presented over NH, which has less affected by constant SST. (To be published from JGR) OSSE using ECMWF data Stoffelen, A., G. J. Marseille, F. Bouttier, D. Vasiljevic, S. De Haan And C. Cardinali 2006:ADM-Aeolus Doppler wind lidar Observing System Simulation Experiment, Quar.J.Roy. Metorol. Soc., 619, Focused on NH due to the lack of radiance data and showed DWL impact over ocean.

Although NOAA and NASA started to work together another Nature Run by FvGCM4 was funded and generated by NASA NASA resources was mostly dedicated to work on NASA Nature Run

7 To be archived in the MARS system at ECMWF To access T511 NR, set expver = etwu Copies are available to designated users for research purposes & users known to ECMWF Saved at NCEP, ESRL, and NASA/GSFC Complete data available from portal at NASA/GSFC Contacts: Michiko Masutani Harper Pryor Gradsdods access is available for T511 NR. The data can be downloaded in grib1, NetCDF, or binary. The data can be retrieved globally or for selected regions. Provide IP number to: Arlindo da Silva Archive and Distribution

8 Pressure level data: 31 levels, Potential temperature level data: 315,330,350,370,530K Selected surface data for T511 NR : Convective precip, Large scale precip, MSLP,T2m,TD2m, U10,V10, HCC, LCC, MCC, TCC, Sfc Skin Temp T511 verification data is posted from NCAR CISL Research Data Archive. Data set ID ds Currently an NCAR account is required for access. (Contact (Also available from NCEP HPSS, ESRL, NCAR/MMM, NRL/MRY, Univ. of Utah, JMA, Mississippi State Univ., JPL) Supplemental low resolution regular lat lon data 1deg x 1deg for T511 NR

Data distribution for simulated observation NASA/NCCS received large storage space There is a entry created for Joint OSSE (Not available right now) Make entry to each data set and generating institute, and contact person. People use these data must contact generating institutes.