Wind wonks twistin’ the year away
Scientists to track twisters from coast-to-coast
LONDON - Leave no tornado unturned. Scientists in London located in Southwestern Ontario, Canada’s tornado alley - will spend 2019 tracking twisters coast-tocoast in the most comprehensive analysis of its kind ever done in Canada.
Across the country, about 60 twisters are identified and verified each year, but statistical analyses of weather, population and lightning data suggest the actual number could be almost four times as high, closer to 230 tornadoes annually.
“The goal is to find those missing tornadoes. We think there’s quite a few more happening in Canada,” said lead researcher Gregory Kopp, a Western engineering professor and acting dean of the department. “We’re trying to find out where they’re happening and how strong they are.”
The problem is, Canada is large and sparsely populated. If a tornado touches down in a forest and no one is around to see it, it easily can go undetected and unstudied- a missed opportunity, Kopp said.
“If we’re missing so many of them, we don’t have a true sense of what the risk is,” he said. “Even if they’re occurring in parts of the country where there’s few people, the fact that they’re there actually affects how we determine that risk.”
The project builds on Western’s previous work studying a spate of tornadoes in southern Quebec on June 18, 2017. Wind engineering experts at Western did an extensive ground and aerial survey, uncovering Quebec’s largest tornado cluster yet and one of the worst on record in Canada.
Last year, Western researchers set out to find and document every tornado in Ontario and hone its analysis of twisters from coast to coast.
The researchers discovered 12 previously undetected tornadoes and improved their data on another 10.
Western’s tornado team will use radar and satellite technology to hunt for and document Canada’s tornadoes. The researchers start out by tracking potentially tornadocausing storms using Environment Canada data. If conditions are right for a twister, the team will zero in on the area using ultra high-resolution aerial surveys. The satellite images are so detailed, they can check where things are on the ground with about two to three metres of accuracy, Kopp said.
If the researchers see torn up grasslands or uprooted trees, they can send a surveillance plane up for more images. The ones captured by the plane show where things are on the ground within about five centimetres of accuracy, Kopp said.
“That allows us to identify the individual trees, it allows us to identify structures that have been damaged,” he said. “From that information, we can tell how intense it was and get more details on the track.”
The team may also use drones or send observers to touchdown sites. Western sent a research team to the Ottawa area, specifically Dunrobin, Ont., and Gatineau, Que., after three tornadoes ripped through in September, damaging hundreds of buildings and knocking out power to tens of thousands. Studying tornadoes - and learning where and when hidden ones happen - is important for everything from honing public alert protocols to mitigating storm damage.
Getting a fuller picture of Canada’s tornado landscape can guide engineers to design houses better suited to storm-prone areas.
“We can mitigate a lot of the damage to houses and other structures with relatively little cost,” Kopp said. “Like the event in DunrobinGatineau, if we had our way and managed to change the (building) code to make houses resilient, we could have stopped a lot of that damage.”
The research is being completed through a partnership between Western’s engineering department and the meteorological research division of Canada’s Department of Environment and Climate Change.
Environment Canada has its own tornado tracking and public warning system, but when a twister lands in a remote area with no one around to report damage, the agency doesn’t always get the feedback it needs to fine-tune its forecasting models, Kopp said.
“We get them ground truth so they can continually improve their models, which will improve safety for Canadians generally,” he said. “We’ll get better warnings, better forecasts.”
Western University engineering professor Greg Kopp and his team of tornado researchers are leaving their labs and windtunnels to try and find all the tornadoes in Canada for 2019. Kopp will be relying on satellite imaging to show researchers debris or damage trails on the ground, which are the visible scars left by tornadoes.