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ECMWF Status Report Operational changes since 16 th North America / Europe Data Exchange Meeting

ECMWF Status Report Operational changes since 16 th North America / Europe Data Exchange Meeting. Jean-Noël Thépaut, Adrian Simmons ( Antje Dethof, Niels Bormann, Graeme Kelly, Christina K öpken, Matthew Szyndel, Lüder Von Bremen, Tony McNally).

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ECMWF Status Report Operational changes since 16 th North America / Europe Data Exchange Meeting

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  1. ECMWF Status ReportOperational changes since 16th North America / Europe Data Exchange Meeting Jean-Noël Thépaut, Adrian Simmons (Antje Dethof, Niels Bormann, Graeme Kelly, Christina Köpken, Matthew Szyndel, Lüder Von Bremen, Tony McNally)

  2. Evolution of forecast skill for the northern and southern hemispheres

  3. Operational forecasting system changesand data impact studies carried out since June 2003 Cycle 26r3 (October 2003) Cycle 28r1 (March 2004) Data impact studies Other operational changes Short-term plans

  4. Cycle 26r3 (October 2003) • First operational assimilation of AIRS data • AMSU-B on NOAA16 and 17 • AMSU-A on AQUA (4th AMSU-A!) • Clear Sky WV radiances from Meteosat 5 (India), GOES 9 (Japan) and 12 (replaces GOES 8) • AMV from GOES 12 • Assimilation of MIPAS ozone retrievals • New humidity analysis • Inclusion of Japanese profilers • New TL radiation scheme in the 4D-VAR • HALO approach to radiative computations sampling • New aerosol climatology

  5. First operational usage of AIRS data: Security • Input radiance data consists of 324 selected channels sampled 1 / 9 locations (from NASA / NESDIS-ORA in BUFR format) • All channels flagged clear at a location are assimilated (excluding channels in the O3 band or 4.2 micron band and low level channels over land) • Flat bias correction (single global number) used for each channel • Very simple (and conservative) observation error assigned to each channel (varying between 0.6 / 1.0 / 2.0K)

  6. AIRS radiance monitoring (1) All channels summary Map of bias / sdev H20 band Detailed Time series 15 µm band Single channel details shortwave band Hovmoller time series O3 band

  7. AIRS impact on the analysis and forecast RMS of 500hPa geopotential forecast error averaged over 40 days (Dec 02/ Jan 03) [AIRS error] minus [CTRL error] The assimilation of AIRS radiances shows a small but consistent positive impact on the analysis and forecast quality in all areas Day-3 RMS T increments (500hPa) at radiosonde locations Day-5 Day-7

  8. Impact of individual sounding instruments on forecast quality Anomaly correlation of 500hPa height for the Southern Hemisphere (average of 50 cases summer and winter 2003 verified with OPS analyses) Results much more neutral in the Northern Hemisphere

  9. Impact of AMSU B

  10. Four AMSU-A instruments

  11. Impact of 4th AMSU-A in cy26r3 Better sampling of areas close to rain Better discrimination of earth surface effects The large improvement may indicate that AMSU-A obs errors were overestimated

  12. Total column ozone – Ozone hole 16 Sept. 2003 O-suite E-suite (26r3) TOMS

  13. Clear Sky Water Vapour Radiances (“CSR”) • Global Use of WV CSR controls the Tropical Upper Tropospheric Humidity in the ECMWF model Difference of fit to NOAA-16 WV channel between “CONTROL” and “NO CSR” Green/blue values indicate a improved fit to NOAA-16 thanks to the use of CSR Mean over 30 days

  14. Cycle 28r1 (March 2004) • New snow analysis, using NESDIS snow cover • Passive monitoring of MSG (winds and radiances) • Use of GOES BUFR AMVs • Semi-lagrangian fix for polar vortex instabilities • Reintroduction of assimilation of ERS2 scat winds, CMOD5 function for backscatter • Introduction of unresolved bathymetry effects for wave model • Use of wind stress to force the wave model

  15. Background: • NOAA/NESDIS disseminates GOES AMVs in new format operat. (autumn 2002) • WV AMVs can be distinguished between clear and cloudy • low-level visible AMVs are included • quality information (Eumetsat QI) is included usage of GOES BUFR AMVs Advantage:consistent usage of GOES and METEOSAT winds • Only WV cloud winds • Vis winds • height selection same as METEOSAT • data selection by highest noFirst Guess QI • 200km thinning box scale Results: • improved forecast over SH and Europe • fewer biased data are used over the Tropics • smaller high level increments over East-Pacific • fingerprints of the low-level VIS winds

  16. Impact on 500Z forecast scores (45 days) NH SH CTL New GOES Europe N-Amer

  17. MSG Atmospheric Motion Vectors MET-8 AMVs with QI>90 against current MET-7 usage MET-7 (current QI thresholds) pressure [hPa] Obs-FG [m/s] Latitude MET-8 10.8m 6.2m 0.8m 7.3m QI>90 QI>90 QI>90 QI>90

  18. MSG WV radiances versus MET-7 WV radiances 25th August MSG 6.2µm MET-7 WV MSG 7.3µm

  19. Met-7 RH Increment

  20. Met-8 RH Increment

  21. Met-8 Impact <90% <90% <90% 95% 99.5% 99.8% <90% <90% 90% 95% 98% 99.5% <90% <90% <90% <90% <90% 99% 95% 99.5% 95% 95% 95% 98%

  22. Conclusions • MSG (METEOSAT-8) looks healthy: • CSR stable and with good noise characteristics • AMVs (if used with High QI) are slightly better than Met-7 ones • Consolidation of forecast impact needed

  23. Data impact studies: • Consolidation of low and high resolution OSES to assess the merit of surface Observing System (Thépaut and Kelly, 2004) • Consolidation of high resolution OSES to assess globally the quality of space and conventional Observing systems (Kelly et al., 2004) • Impact Studies of main types of conventional and satellite humidity data (Andersson et al., 2004)

  24. Impact of Atmospheric Motion Vectors in the OSEs • Global use of AMVs has a positive impact in the ECMWF forecast model (specially in terms of tropical wind scores) TROPICS 200 hPa vector wind Mean over 120 cases

  25. Humidity OSEs – Summary (1) OSEs were performed with cy26r3, using the new humidity analysis. The AN and FC impacts of 2 types of surface-based and 5 types of space-based observing systems have been tested. • SSMI dominates over sea, then AMSUB • RS, SYNOP and AMSUB dominate over land • GEOS, HIRS and AIRS dominate at 200-300 hPa • Analysis increments for SSMI peak at 850, AMSUB at 400/500, GEOS at 300, AIRS at 200 hPa.

  26. Humidity OSEs – Summary (2) Abundance of biases: • SSMI adds water in tropics • SSMI removes water from parts of the N.Hem storm-tracks • RS are biased w.r.t model in many regions (Mexico, USA, S. Europe, India, China. • SYNOP add water at 925 hPa in most regions. • RS and SYNOP show opposite bias at 925 hPa. • AMSUB removes water from Siberia and Sahara – adds water over tropical land. • HIRS dry bias over Antarctic ice. • AIRS is biased in tropics at 200 hPa.

  27. Humidity OSEs – Summary (3) Precipitation: • Only SSMI affects mean tropical precipitation to a significant degree. Spin-down is increased with SSMI. • All other observing types appear near-neutral w.r.t spin-down in tropical precipitation. • RS and SYNOP RH biases are reflected in precipitation over N. America and Europe • SSMI, AMSU-B, HIRS and GEOS affect precipitation in W. Pacific storm track. • SSMI reduces rainfall in N.Atlantic Storm track.

  28. Other main operational changes • Blacklist GOME total ozone from ERS-2 (18/8/2003) • End of NOAA17 AMSU-A (31/10/2003) • Blacklist temporarily AQUA (AMSU-A and AIRS) during solar storm (11/2003) • Actions (blacklist/bias correction) against various Meteosat calibration • Blacklist NOAA-15 AMSU-A channel 6 due to a drift in the monitoring statistics (17/2/2004) • Passive monitoring of KNMI SCIAMACHY profile data (16/03/2004) • Blacklist MIPAS to prevent a sudden come back! (10/5/2004) • Blacklist HIRS from NOAA-16 (25/5/2004)

  29. Short term plans (operational targets) • 2Q04 Early delivery system • 3/4Q04 Rain-affected mw radiance assimilation Use of MSG and SSMIS data Regional variation to Jb covariances New PBL and Turb. orog.-drag schemes Various other refinements • 4Q04/1Q05 Increased vertical resolution New cloud and stochastic physics schemes Improved perturbations for EPS • Later in 05 Increased horizontal resolution

  30. Short-term plans (specific to use of observations) • Improve the day-1 AIRS assimilation system • Implementation of RTTOV8 in IFS • Improved MW surface emissivity over land • Improved use of AMSU-A over land • Monitoring and assimilation experiments with SSM/IS • Monitoring and assimilation of MSG winds (VIS/IR/WV) • Monitoring and assimilation of MSG WV radiances • Monitoring ground-based GPS network • Assimilation of SCIAMACHY ozone profiles • CHAMP data? (RO assimilation ready) • Continue to explore limb radiance assimilation

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