1. Slide 1 Sakari Uppala and Dick Dee European Centre for Medium-Range Weather Forecasts ECMWF reanalysis: present and future

2. Slide 2 CONTENTS Background ERA-15  ERA-40  ERA-Interim Product quality Reanalysis plans at ECMWF

3. Slide 3 ECMWF reanalysis projects ERA-15 1979 – 1993 ERA-401957 – 2002 ERA-Interim1989  … ECDAS

4. Slide 4 Operational forecast performance 1980-2007 Northern Hemisphere 500 hPa geopotential ANC reaching 60% Southern Hemisphere 500 hPa geopotential ANC reaching 60% Tropics 850 hPa wind vector ABC reaching 70% 200520001985198019901995 200520001985198019901995 200520001985198019901995 Monthly time series Moving average ERA-15ERA-40 ERA-Interim

5. Slide 5 ECMWF reanalyses ERA-40 1957-2002 ERA-15 1979-1993 Improved data assimilation system -Assimilating model T159L60 -3D-Var FGAT -Analysis of O 3 More extensive use satellite radiances ERA-15 experience  ERA-40 blacklist More comprehensive use of conventional observations Use of Meteosat reprocessed winds, CSR data passive Improved SST & ICE dataset Ocean wave height analysis

6. Slide 6 VTPR 1973 TOMS/ SBUV 1979 TOVS: HIRS/ MSU/ SSU Cloud Motion Winds 1987 SSM/I 1991 ERS-1 1995 ERS-2 1998 ATOVS:AMSU-A METEOSAT Reprocessed Cloud Motion Winds 1982 1988 CONVENTIONAL SURFACE AND UPPERAIR OBSERVATIONS NCAR/ NCEP, ECMWF, JMA, US Navy, Twerle, GATE, FGGE, TOGA, TAO, COADS, … AIRCRAFT DATA 1973 1957 2002 Observing Systems in ERA-40

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8. Slide 8 Trend and variability in two-metre temperature CRUTEM2v (Jones and Moberg, 2003) ERA-40 Linear trend (1979-2001): CRUTEM2v0.31 O C/decade ERA-400.28 O C/decade NCEP0.19 O C/decade

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10. Slide 10 Satellite radar altimeter 1992-2003 (Davis et al. Science 2005 Vol 308 No. 5730) Surface elevation change rate (cm per year): 1992  2003 Precipitation change (cm of snow per year): ERA-40 (1992-2001)+ ECMWF OP (2002-03)

11. Slide 11 The Great Flood of 1953 The greatest surge on record for the North Sea as a whole occurred on 31 January and 1 February 1953. In the Netherlands 1,800 people drowned and in eastern England 307 people died.

12. Slide 12 February 1953 00UTC The 500 hPa “Carpet” donated to ECMWF by the Netherlands

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14. Slide 14 Analysis Sunday 1 February 1953 00UTC 500 hPa geopotential

15. Slide 15 Forecast +7D Analysis 1 Feb. 1953T+168 hours

16. Slide 16 Wave Analysis 1 Feb. 1953T+36 hour Wave forecast

17. Slide 17 Serves as an intermediate reanalysis before the next extended reanalysis Assimilation has reached September 2004 and will reach real time in the end of 2008 1989 - 1998 products publicly available Input data based mainly on ERA-40 and ECMWF operational observations with a few reprocessed datasets ERA-40 1957-2002 ERA-Interim 1989  to continue as CDAS 

18. Slide 18 Data-assimilation system T159L60  T255L60 / 12 hour 4D-Var New humidity analysis and improved model physics Satellite level-1c radiances Better RTTOV and improved use of radiances, especially IR and AMSU Assimilation of rain affected radiances through 1D-Var Variational bias correction Improved use of radiosondes Bias correction and homogenization based on ERA-40 Correction of SHIP/ SYNOP surface pressure biases Use of reprocessed - Meteosat winds - GPS-RO data CHAMP / UCAR 2001 , GRACE and COSMIC - GOME O3 profiles 1995  New set of Altimeter wave height data 1991  ERA-40 1957-2002 ERA-Interim 1989  to continue as CDAS 

19. Slide 19 Daily mean total column water vapour 1989-1998

20. Slide 20 Daily mean total column water vapour 1989-1998, ERA-Interim-ERA-40

21. Slide 21 Daily mean total column water vapour 1989-1998, ERA-Interim-SSM/I

22. Slide 22 Global Total Column Water Vapour

23. Slide 23 Mean daily precipitation,1989-1998, ERA-Interim

24. Slide 24 Mean daily precipitation, 1989-1998 ERA-Interim-ERA-40

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26. Slide 26 Tropical Ocean areas

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29. Slide 29 Forecast performance, ERA-40, ERA-Interim and Operations

30. Slide 30 Research & Development as a collaborative effort 2009-2011 Start of production in 2012 1938  2015 and continue as CDAS Important components – Recovery, organization and homogenization of observations – Improved SST & ICE dataset – Variational analysis technique aimed for reanalysis – Comprehensive adaptive bias handling – Handling of model biases – Coupled atmospheric-ocean reanalysis? ERA-Interim ERA-75?

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33. Slide 33 4D-Var CONTROL All observations 3D-Var “Surface pressure observations only” 4D-Var “Surface pressure observations only” 15 February 2005 00 UTC 500 hPa analysis