Ground Generator Experiment (GGAP)

Ground Generator Assessment Program

At the request of Alberta Agriculture, the Alberta Research Council mounted an effort to evaluate the I.P. Krick weather modification technique. This technique used ground-based silver iodide generators of the coke and arc types. A contract was signed with I.P. Krick Associates of Canada, Ltd. authroizing the operation of as many as 70 coke and 15 arc generators to deliver silver iodide artificial nuclei to a target area southeast of Calgary.

The operational objective of the Krick company was to suppress hail and increase rainfall in the target area. The research objective of the Alberta Research Council was to assess the ability of the Krick system to generate and deliver ground generator effluent to prescribed target volumes in the atmosphere. This program of operations and research was designated the Ground Generator Assessment Program (GGAP).

To meet the operational and research objectives of GGAP, it was necessary to conduct day-to-day operations of the Krick system, to monitor generator network operations, to conduct laboratory tests of generators, and to obtain in-situ measurements of ice nuclei concentrations.

The ARC monitoring program consisted of visits to generator sites to verify their operational status and collect generator fuel samples. The Colorado State University Cloud and Aerosol Simulation Laboratory performed tests of generator effectiveness and rates of nucleation using generators provided by the Krick company. In-situ measurements of ice nuclei concentrations were made using a Colorado State University Mee ice nucleus counter mounted onboard the INTERA/ARC research aircraft.