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Sakari Uppala and Dick Dee European Centre for Medium-Range Weather Forecasts. ECMWF reanalysis: present and future. Background ERA-15 ERA-40 ERA-Interim Product quality Reanalysis plans at ECMWF. CONTENTS. ERA-15 1979 – 1993 ERA-40 1957 – 2002
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Sakari Uppala and Dick Dee European Centre for Medium-Range Weather Forecasts ECMWF reanalysis: present and future
Background ERA-15 ERA-40 ERA-Interim Product quality Reanalysis plans at ECMWF CONTENTS
ERA-15 1979 – 1993 ERA-40 1957 – 2002 ERA-Interim 1989 … ECDAS ECMWF reanalysis projects
ERA-40 ERA-15 1980 1980 1980 1985 1985 1985 1990 1990 1990 1995 1995 1995 2000 2000 2000 2005 2005 2005 Operational forecast performance 1980-2007 ERA-Interim Monthly time series Moving average Northern Hemisphere 500 hPa geopotential ANC reaching 60% Tropics 850 hPa wind vector ABC reaching 70% Southern Hemisphere 500 hPa geopotential ANC reaching 60%
Improved data assimilation system Assimilating model T159L60 3D-Var FGAT Analysis of O3 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 ECMWF reanalyses ERA-40 1957-2002 ERA-15 1979-1993
Observing Systems in ERA-40 2002 1957 METEOSAT Reprocessed Cloud Motion Winds 1982 1988 1979 TOMS/ SBUV 1973 AIRCRAFT DATA CONVENTIONAL SURFACE AND UPPERAIR OBSERVATIONS NCAR/ NCEP, ECMWF, JMA, US Navy, Twerle, GATE, FGGE, TOGA, TAO, COADS, … 1973 1979 1987 VTPR TOVS: HIRS/ MSU/ SSU SSM/I 1991 ERS-1 1995 Cloud Motion Winds ERS-2 1998 ATOVS: AMSU-A
CRUTEM2v (Jones and Moberg, 2003) ERA-40 Trend and variability in two-metre temperature Linear trend (1979-2001): CRUTEM2v 0.31OC/decade ERA-40 0.28OC/decade NCEP 0.19OC/decade
Precipitation change (cm of snow per year): ERA-40 (1992-2001)+ ECMWF OP (2002-03) Satellite radar altimeter 1992-2003 (Davis et al. Science 2005 Vol 308 No. 5730) Surface elevation change rate (cm per year): 1992 2003
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.
February 1953 00UTC The 500 hPa “Carpet” donated to ECMWF by the Netherlands
Sunday 1 February 1953 00UTC 500 hPa geopotential Analysis
Forecast +7D Analysis 1 Feb. 1953 T+168 hours
Wave Analysis 1 Feb. 1953 T+36 hour Wave forecast
ERA-Interim 1989 to continue as CDAS ERA-40 1957-2002 • 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-Interim 1989 to continue as CDAS ERA-40 1957-2002 • 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
Daily mean total column water vapour 1989-1998
Daily mean total column water vapour 1989-1998, ERA-Interim-ERA-40
Daily mean total column water vapour 1989-1998, ERA-Interim-SSM/I
Mean daily precipitation, 1989-1998 ERA-Interim-ERA-40
ERA-75? ERA-Interim • 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?
15 February 2005 00 UTC 500 hPa analysis 4D-Var CONTROL All observations 3D-Var “Surface pressure observations only” 4D-Var “Surface pressure observations only”