THE OSSE FOR NPOESS

Michiko Masutani

Kenneth Campana, and Stephen J. Lord (PI)

EMC/NCEP/NWS/NOAA

http://nic.fb4.noaa.gov:8000/research/osse

Figures

Zonal mean of total cloud cover
Nature run clouds
Observed clouds
Table for Data withdrawal experiments
Skill curves (wind withdrawal)
Skill curves (Temperature withdrawal)
Skill curves (TOVS radiance withdrawal)
RMS error curves (wind withdrawal)
RMS error curves (Temperature withdrawal)
RMS error curves (TOVS radiance withdrawal)
DWL experiments table


OSSE

: Observing System Simulation Experiments

NPOESS

: National Polar-orbiting Operational Environmental Satellites
scheduled to be launched 2007-2010

Objective:


To test the impact of the new instruments using simulated data
To make recommendations for configuration based on quantitative NWP impact of NPOESS instruments

Advantages:


Prepare for operational use of new data
Data base
Evaluate operational computing and storage requirements
Development of data assimilation system
Gain some knowledge on the new instrument
Data can be used very soon after launch

Instrument:


DWL (Doppler Wind Lidar )
AS (Advanced Sounder)


OSSE test data assimilation systems


NCEP(the National Centers for Environmental Prediction)
J. Derber, J. Woolen, W.-S. Wu, and other NCEP Staff
DAO (NASA/data assimilation office)
R. Atlas and J. Terry, G. Brin
NRL (the Naval Research Laboratory)
R. Daley


Simulation of NPOESS candidate instrument data


DWL: G. D. Emmitt, S. Wood and S. Greco and others
TOVS radiance:T. Kleespies (NESDIS)
Conventional data :
J. Terry and R.Atlas (DAO)

Advised by

: Drs. E. Kalnay, W. Baker, and R. Daley , review Pannel

Supported by

: Dr. Steven Mango (Integrated Program Office)

Nature run

(True Atmosphere for the OSSE)

Description


ECMWF reanalysis model T213 and 640x320 grid 31 levels
Free forecast integration from 5 February 1993 to 7 March 1993

Acknowledgments: Data Services Section of ECMWF,
Roger Saunders(ECMWF) and Anthony Hollingsworth (ECMWF)

Evaluation


- Representativeness of February 1993
Near normal SSTA , Breaking up MJO
- The nature run found to be representative to the actual atmosphere in many ways.
-The major problem so far :
More low level cloud over land and lack of low level cloud over ocean.
Must test sensitivity of simulated observations distribution and quality to cloud amount.
Acknowledgments: Christian Jakob(ECMWF) , S. K. Yang (CPC/NCEP), L. Stowe (NESDIS), K. Campana (EMC/NCEP)

Data withdrawal experiments with actual data


Withdraw
TOVS radiance, RAOB temperature, or RAOB wind

Results



- TOVS radiance has wider impact than RAOB temperature in temporal structure and geographical distribution
-RAOB wind has highest impact on NH forecast skill score
- Wind contribution is more important than temperature
- Satellite data impact is complementary to that of RAOB winds.
(Note NH has more RAOB making satellites
harder to show the impact.)

Implication



Space based DWL can potentially produce positive impact
3-D coverage needed
penetrating thin clouds required

Progress


DWL wind processing almost completed.
volume is about equal to that of current conventional data
NCEP data assimilation (SSI) has been upgraded to use LOS winds.

Plan


DWL data will be tested with real observations to examine analysis sensitivity
Simulated conventional data is in preparation
Perform sensitivity test for simulated data set for existing Instruments.
Perform sensitivity test for simulated data set for future Instruments.

Work on other potential instruments.