1. Short Introduction ZAMG, WLKC733 Thomas Krennert, ZAMG – Vienna, Synoptic Department email: t.krennert@zamg.ac.at

2. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 ZAMG / SYN subjective

3. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 Start: ~1954 with Baur / Lauscher Usable records from ~1959 1957 - 1959 reconstructed Individual knowledge of forecaster included: mixture of methods continued Baur Lauscher Hess-Brezowski Schuepp Steinacker More than 80 classes found Reduced to 43 / digitalized (-) Still identical classes (-) Only regards small domain (+) Largest catalogue of air mass analysis and frontal passages

4. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 Classification: 43 Types Air mass analysis: upper level ( 850 hPa) Change of air mass: 2 levels during the day Frontal passage: type and time of passage over Vienna / Austria. Air mass analysis and frontal passages are missing for the years: 1957 - 1960 1968 - 1970 1976 1982

5. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008

6. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 WLKC733

7. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 Flow pattern direction including indication of cyclonicity and precipitable water Each parameter could be investigated seperately (alphanumeric output) More equally distributed on smaller domains Applicable only for small domains Easily applicable operationally Advantage within areas with orography

8. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 Method: First two letters denote main wind sector number counting clockwise: sector 01=NE, 02=SE, 03=SW, 04=NW, 00=undefined (varying directions) Wind direction at 700 hPa indicates flow Derived from u-, v- components of true wind 2/3 of all weighted wind directions have to be connected to a sector of 10° Sector is assigned to a quadrant (i.e. SW = [190°, 280°]) Third letter denotes >A C<yclonicity at z925. 4th letter denotes >A C<yclonicity at z500. For each grid point Weighted area mean value is calculated [gpdm2/km2 * 10.000] 5th letter denotes >D W<et. Weighted area mean value of precipitable water (whole atmosphere) Compared to area daily mean value (annual variation) Indicating values above or below of daily mean

9. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 1)parameters: z925,z500,u700,v700,pw 2)software: code available on cost733 - wiki 3) background: basic knowledge 4) time/CPU: few seconds 5) number of types: 40, could be reduced 7) key-patterns: subjective / thresholds 8) distance measure: thresholds Profile WLKC733

10. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 6) literature: Dittmann, E., 1995: Objektive Wetterlagenklassifikation, Offenbach am Main, Selbstverlag des Deutschen Wetterdienstes, Berichte des Deutschen Wetterdienstes, Band 197. Bissolli, P., 1999: Kommen Westwetterlagen häufiger vor als früher? Klimastatusbericht 1999, 26-30, Deutscher Wetterdienst, Offenbach a.M. Bissolli, P., Dittmann, E., 2001: The objective weather type classification of the German Weather Service and its possibilities of application to environmental and meteorological investigations, Meteorologische Zeitschrift, Volume 10, Number 4, 1 July 2001, pp. 253-260(8)

11. Thomas Krennert, ZAMG – Vienna, Austria, Synoptic Department COST 733 WG2 Meeting Augsburg, March 2008 Adaptations: Subjective weighting (after experiments) Small central domain with dominant weighting 15X 2X 1X