Simulating Silver Iodine Dispersion with WRF: Hail Suppression System Analysis

Abstract

The aim of this article is to study silver iodine (AgI) dispersion in Mendoza using the Weather Research and Forcasting model (WRF). AgI is used to seed clouds in hail suppression systems. In particular, in Mendoza, cloud seeding is done through ground generators located in the western part of the province, were most storm cells form. The efficiency of this hail suppression system has not been scientifically proven. This paper provides a methodology to include AgI sources in WRF in order to study its dispersion in the atmosphere. Because of the physical characteristics of ground generators, they are modeled as area sources using the Fire module of WRF. This module has been design to simulate biomass burning. We show how to simulate AgI generators through definition of a special fuel behavior model to use with WRF-Fire. Through dispersion modeling it is possible to see if AgI reaches storm cells. Furthermore, with simulation results it is possible to choose the best location for ground AgI generators. This paper shows a first approach to simulation of hail suppression system currently working in Mendoza.