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University of Vienna Department of Meteorology and Geophysics. A New 4D Variational Data Analysis Scheme in the Framework of VERA. Wolfgang Gepp. Department of Meteorology and Geophysics, University of Vienna. University of Vienna Department of Meteorology and Geophysics. concept of VERA.
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University of Vienna Department of Meteorology and Geophysics A New 4D Variational Data Analysis Scheme in the Framework of VERA Wolfgang Gepp Department of Meteorology and Geophysics, University of Vienna ICAM 2003
University of Vienna Department of Meteorology and Geophysics concept of VERA interpolation of irregularly distributed data to a regular grid data quality control (error correction) variational algorithm using a form of thin plate splines + a priori knowledge of small scale physical processes (Fingerprints) ICAM 2003
University of Vienna Department of Meteorology and Geophysics „old“ VERA already in operational use valuable analysis and nowcasting tool ICAM 2003
University of Vienna Department of Meteorology and Geophysics Problems with „old“ VERA restricted to 2D insufficencies ICAM 2003
University of Vienna Department of Meteorology and Geophysics we want more reliable results avoid insufficencies include vertical sounding data analyse 3D phenomena temporal extrapolation ICAM 2003
University of Vienna Department of Meteorology and Geophysics extend algorithm to 3D and 4D VERAXX ICAM 2003
University of Vienna Department of Meteorology and Geophysics why a new scheme? old algorithm becomes expensive for 4D keep algorithm simple for usual commercial PC platforms ICAM 2003
University of Vienna Department of Meteorology and Geophysics VERAXX VERA ICAM 2003
University of Vienna Department of Meteorology and Geophysics 10x10x10x10 10000 gridpoints 10000 equations ICAM 2003
University of Vienna Department of Meteorology and Geophysics solution Partial Grid Calculation 5x5x5x5 subdomain max. 625 equations ICAM 2003
University of Vienna Department of Meteorology and Geophysics Partial Grid Computation ICAM 2003
University of Vienna Department of Meteorology and Geophysics how get data into calculation? VERA pentagons out of stations VERAXX stations usually not at gridpoints derive gridpoint values from stations ICAM 2003
University of Vienna Department of Meteorology and Geophysics Deriving Grid Point Values 2 1 A dy dx 3 4 ICAM 2003
University of Vienna Department of Meteorology and Geophysics First VERAXX results only 3D calculations so far no Fingerprints used error correction from VERA ICAM 2003
University of Vienna Department of Meteorology and Geophysics Horizontal Cross Section H=220m Zell am See, 15. Nov. 2002, 1800 UTC ICAM 2003
University of Vienna Department of Meteorology and Geophysics Vertical Cross Section N S Zell am See, 15. Nov. 2002, 1800 UTC ICAM 2003
University of Vienna Department of Meteorology and Geophysics More Information? http://www.alpenwetter.net http://www.univie.ac.at/img-wien/vera ICAM 2003