1. Institut für Physik der Atmosphäre 1 Evaluation of a numerical thunderstorm study with POLDIRAD and lightning observations Oberpaffenhofen, 8 February 2002 Thorsten Fehr Institut für Physik der Atmosphäre Deutsches Zentrum für Luft- und Raumfahrt, e.V. (DLR)

2. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 2 Motivation Investigation of Nitrogen oxides (NO x ) produced by lightning Idealized case study with realistic dynamics Evaluation of simulation results with observations EULINOX Project Excellent data coverage for the 21 July 1998 storm Radar, lightning, aircraft, radiosondes...

3. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 3 Lightning and Polarimetric Radar ONERA ITF System 3D-Detection of Lightning (114 MHz) Interferometer DLR Polarimetric Doppler Radar: POLDIRAD C-Band ( = 5.45 cm) Doppler Winds Polarimetric Capabilities Hydrometeor Classification BLIDS: Siemens AG 2D-Positioning (VLF/LF) Time-of-Arrival

4. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 4 Numerical Model Mesoscale Model MM5 non-hydrostatic Bulk microphysics flat orography Resolution x=1km 50 vertical levels Initialization : Single Sounding Hot Bubble Lightning Parameterization Modified approach by Price and Rind, 1998 Total Flash Frequency: f fl = 1.29x10 -6 w max 4.55 Ratio of intracloud (IC) to cloud-to-ground(CG) flashes: = f IC /f CG = P 4 (Z fr )

5. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 5 Radar and Model MM5 (1.5°)POLDIRAD (1°)

6. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 6 Radar and Model: Supercell

7. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 7 Lightning and Model

8. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 8 Lightning and Model: Supercell Good Correlation during strong convection Poor correspondence during decay/strati- form stage Parameterization cannot applied for the complete lifecycle New Concepts (?)

9. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 9 ITF Lightning Data and POLDIRAD (I) Reflectivity and 1 min of ITF activity

10. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 10 ITF Lightning Data and POLDIRAD (II) Classification: Höller et al., 1994 21 July 98 Storm Most flashes in graupel/hail regions Graupel Hail

11. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 11 Conclusions for Model Supercell Comparison with Radar data shows significant similarities The lightning parameterization produces comparable flash frequencies for the convective regime Simulated Supercell represents the observed storm in general dynamical and microphysical properties Model storm can be use for further studies (lightning NO x, development of new parameterizations,...)

12. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 12 Outlook Improved lightning parameterization: F lightning = F lightning (v i, q i, v i, q i ) Radar Polarimetry Assimilation of meteorological parameters derived from lightning observations, e.g.: z = z (f CG ) RR = RR(f lightning ) Adverse weather warning

13. Thorsten Fehr, Institut für Physik der Atmosphäre, DLR 13