Seeding storms: Alberta thunderstorm reduction team kicks off busy season

Storm season is ramping up and the Alberta Severe Weather Management Society is already putting planes in the air to help reduce the severity and resulting damage of thunderstorms.

Alberta Severe Weather Management Society project director says storm activity has picked up over past 5 years

Alberta Severe Weather Management Society's goal is to reduce property damage by decreasing the intensity of storms. ASWMS project director Terry Krauss says the last five years have been their busiest in the 22-year history of the organization. (Shutterstock/Denis Rozhnovsky)

Storm season is ramping up and the Alberta Severe Weather Management Society (ASWMS) is already putting planes in the air to help reduce the severity and resulting damage of thunderstorms.

Terry Krauss, a project director with the organization, says ASWMS has already had their cloud seeding planes in the air twice since the June 1 start of the season, seeding five storms.

"We want to speed up the rain process, and if it rains early, that can help suppress the dynamics of the storm and make it into a rain storm instead of a violent, severe thunderstorm with hail," said Krauss, who is also a cloud physicist and metrologist. 

Cloud seeding works by putting chemicals — silver iodide and smoke particles — into the feeder clouds of a storm in order to create more ice crystals, which then compete for the available liquid water.

"It competes for the water so that it produces may small hailstones," Krauss said. "We hope that they melt completely and fall to the ground as rain or fail to the ground as small hail and therefore cause no property damage."

Krauss says the Alberta Research Council estimates the ASWMS's cloud seeding efforts are responsible in a 20 per cent reduction in the province's severe thunderstorms.

The ASWMS has seen an uptick in storm activity over the past few years, says Krauss, with the last five being busier than the 15 that came before. 

Despite their best efforts, sometimes the large, damaging hail still manages to slip through.

"For a large storm, there can be three, four, five feeder clouds popping at the same time and merging with the storm and our seeding might only seed two or three," he said.

Hail storms in the province over the past five years have caused over a billion dollars in damage. 

Seeding season starts at the beginning of June and ends Sept.15. Krauss says the ASWMS flies an average of 30-35 days per season and seeds an average of 100 storms. 

With files from CBC Calgary News at 6