Based on a straightforward physical model, a new lightning parameterization has been developed: A two-plate capacitor represents the basic dipole charge structure of a thunderstorm, which is charged by the generator current and discharged by lightning. In this approach, the generator current as well as the discharge strength are parameterized using the graupel-mass field. In order to test this approach, Polarimetric radar data were used, from which the graupel distribution in observed thunderstorms could be inferred. The lightning activity was detected using the LINET network. The comparison between theoreticallypredicted and measured flash rates is encouraging. The new parameterization, as well as existing approaches were implemented in the COSMO-DE model. With this model, realworld convective scenarios were simulated. A comparison between modeled and observed flash rates of individual clouds using the new approach yielded promising results. The comparison of the bulk lightning activity over a large area suggests that none of the parameterizations captures the overall lightning activity well. This is mainly because COSMO-DE does not simulate the observed number of cells at the correct times.
|Translated title of the contribution||The development of a new lightning-frequency parameterization and its implementation in a weather prediction model|
|Number of pages||152|
|Journal||DLR Deutsches Zentrum fur Luft- und Raumfahrt e.V. - Forschungsberichte|
|State||Published - 2010|
- Lightning frequency