Numerical Simulation of Seeding Effect Using a Bin Microphysics Scheme

The University of Pecs and NCAR Bin microphysical scheme implemented into WRF (UPNB) was used to investigate the effect of seeding on the precipitation formation in the Intensive Observing Period 5 (IOP5) of the SNOWIE (Seeded and Natural Orographic Wintertime clouds: the Idaho Experiment) project. The purpose of the research is twofold: (i) To identify the physical mechanisms impacted by AgI seeding. How do they depend on the location of the seeding and on the environmental conditions? In IOP5, the radar data showed evidence of seeding effect with sharp increase in reflectivity in the aircraft released AgI plumes. Simulated cloud properties related to the seeding case and to CTRL (unseeded) will be compared against in-situ and remote sensing data. (ii) To investigate how the seeding impacts the spatial distribution of the precipitation. Our previous 2D studies indicated that in some environmental conditions that seeding could result in a significant decrease of the accumulated surface precipitation on lee side. Calculated surface precipitation will be compared with snow-gauge data.