Overview and results from the Mexican hygroscopic seeding experiment

In response to a severe drought in the early 1990's the State of Coahuila and local industry started to explore the possibility of increasing rainfall through the application of cloud seeding technology. The Program for the Augmentation of Rainfall was a four-year program to conduct a scientific evaluation of cloud seeding to enhance rainfall using hygroscopic flares. The program consisted of physical studies, a randomized seeding experiment, and collaboration and training of Mexican scientists and students.

During 1996 the emphasis was on establishing the infrastructure and operational procedures for collecting data to assess the weather conditions and cloud characteristics in the region. Based on these results a randomized cloud seeding experiment was started in 1997 using the South African hygroscopic flares. The randomized experiment was conducted to replicate the earlier experiment conducted in South Africa. The randomized experiment was only conducted for two years. Due to lack of funding the final year could not be completed. However, the results from the randomized experiment already showed encouraging results.

The paper will provide an overview of the program including the equipment and physical measurements, design of the randomized seeding experiment, some results of the physical studies, and results from the two years of randomized seeding.