COSITRACKS Leading Institution

Forschungszentrum Karlsruhe
Institut für Meteorologie und Klimaforschung
Prof. Ch. Kottmeier (Speaker)

Poject team: Christoph Kottmeier,  Klaus-Dieter Beheng, Christian Barthlott, Ulrich Corsmeier

Activities within

Measurements on the initiation of convective systems and their transition to convective storms performed within the experiments CMOS, CSIP, and COPS

  • Analysis of the three-dimensional structure of convection cells based on a combination of in-situ and remote sensing data obtained from the ground (Doppler-Lidar), from radiosondes and aircraft (DO 128).
  • Determination of surface parameters (evaporation, vegetation, orography) and internal parameters (thermal stratification, shear) influencing the migration speed and direction of convective systems.
  • Study of lateral and vertical entrainment of environmental air by clouds with airborne turbulence measurements.

Damage assessments

  • The frequency of thunderstorms for a period of 30 years will be merged with data of insurance companies on damage related to thunderstorms (hail, flash floods, gales). From a combination of data, a measure of losses caused by thunderstorms will be calculated.

Case studies and statistics of Convective Storms based on Radar data and numerical modelling

Data of the IMK C-Band radar, available since 1997, may give hints to sites favourable for initiation of convection and may give insight into the development of structures of clouds. A tracking algorithm (TRACE3D) is applied for detecting and tracking 3-D cloud structures. Lightning data of the BLIDS system (operated by SIEMENS) will be incorporated into TRACE3D for revealing dependencies between cloud development and lightning. Furthermore, initiation and development of convective clouds are studied by a cloud-resolving atmospheric model having included a novel cloud-microphysical scheme. Specific objectives are

  • the investigation of microphysical structures, with focus on precipitation formation, including quantitative determination of precipitation in convective clouds with C-Band radar, accompanied by evaluation of lightning data and by numerical simulations with a cloud resolving weather forecast model operating with a novel parameterization of mixed-phase cloudmicrophysics;
  • the determination of area-averaged precipitation from convective clouds as a function of external and internal parameters and the type of convection derived from radar data.