The Decibel - Why storms are more destructive now

Episode Date: August 25, 2023

There are a lot of serious storms these days, and those storms are causing more and more damage, as residents of California are seeing this week in the aftermath of Tropical Storm Hilary.The storms we are seeing in Canada are changing – but not how you might expect. David Sills, a severe storms specialist and executive director of the Northern Tornadoes Project at Western University, explains what changes he’s seeing in storms, how prepared we are to handle the damage from them, and the connection one of these storms has to a producer here at The Decibel.This episode originally aired on September 14, 2022.Questions? Comments? Ideas? Email us at [e-mail]

This summer, there have been some pretty bad storms. Last week, Tropical Storm Hillary battered Southern California. Tens of thousands of people were displaced as record-breaking rainfall caused mass flooding. In July, tornadoes tore through Ottawa. And in Nova Scotia, four people died in sudden, devastating flash floods. But the most destructive weather could still be on the way, since hurricane season for the Atlantic coast stretches into the fall. Today, we're re-airing this episode with David Sills. He's an extreme storm specialist and executive director of the Northern Tornadoes Project. He'll explain why storms are more powerful and destructive now, and why they could get even worse. I'm Mainika Raman-Wilms,

and this is The Decibel from The Globe and Mail. So today I've got Rachel here with me. Rachel is one of our producers here at The Decibel. Hey, Rachel. Hey. So you're here today because you're actually connected to the story that we're talking about today. So tell me what happened. Oh, man.

So my partner and I bought a piece of land a few months ago. And before we get into what happened, I actually just want to like paint a picture of the land because I feel like it'll help you understand what happened. So this is a four and a half acre lot on a river just north of Tweed, Ontario, which is about two and a half hours northeast of Toronto. There's nothing on it. It's just raw land. So there are massive trees on this property, like pine trees that I would not be able to wrap my arms around. And the stands of sugar maples and cedars that are just, they're glorious. But earlier this summer, it was hit by a tornado. Oh, no. Okay. So tornado goes through and then like, what does it what does it

look like now? All those big trees? Oh, man, it's honestly almost unrecognizable, actually. So we when we drove in, you know, the first weekend we went up after the tornado had hit, we actually drove by our driveway. And that was partially because it was completely covered in fallen trees, but also because we just didn't recognize the land anymore. Like I was driving up and we were looking around and I was thinking to myself, I swear we were at the top of this hill, but this doesn't look anything like what I remember it looked like before. So it's honestly hard to describe the damage.

I've just never seen anything like this before. Basically every tree over 30 feet has either been snapped in half or completely uprooted. And almost everyone on our street lost their roof, lost their shed, lost their garage that they had just finished building, or they had lost all of those things. That sounds pretty intense. Were the people okay who were there? Thankfully, yes. Everyone on our street was fine. There were some injuries reported in other areas, but thankfully no one in the tornado was killed. This is actually kind of interesting to me because we don't really think about

tornadoes as an Ontario problem. Like it seems like the kind of thing that happens elsewhere, but we don't really see it happening in this province as much, I would think. Totally. This is something I've heard from everyone that I've been telling about this, you know, that we don't think of tornadoes as something that happened in Ontario, but we actually get a lot of them here. And we get a lot of them in Canada sort of more broadly. And for me, it feels like we've been seeing a lot of really intense storms this year and sort of in the past few years. If you remember, there was that storm back in May, sort of between Toronto and Ottawa that killed more than 10 people. And, you know, we know that climate change is sort of having a big effect on a lot of things. And so I've been curious about how it's affecting storms and severe storms that

we're seeing. So I talked to David Sills. He's a severe storms specialist, and he's the executive director of something called the Northern Tornadoes Project, which is operated out of Western University. So he and I talked about how storms are changing these days and sort of the connection that has with climate change and how prepared we are as a country to deal with the damage from those storms. Wow. This sounds fascinating, Rachel.

I'll let you take it away then. Thanks, Manika. You're listening to The Decibel from The Globe and Mail. David, thank you so much for joining me. My pleasure. So you and your team at the Northern Tornadoes Project are actually looking at the tornado that went through my property. So what do you know about it so far? Well, we know that it was more than 1.4 kilometers wide at its maximum and about 55 kilometers in length.

So it was a really long wide tornado it's probably up there in the top 10 percent at least of tornadoes as far as length and width in canada so it was a bit of a beast uh but the the rating on it was ef2 which is kind of middle of the pack EF scale goes from 90 kilometers per hour at the EF0 level up to over 315 kilometers per hour up at EF5. Okay, right in the middle of the road. But to me, it feels like there was a lot of damage. So have you sort of assessed how much damage there was and sort of how complicated the damage was because of this tornado? In this particular case, we actually flew drones. And in fact, we're going to have an aircraft fly over the entire length of the track. It's too much for drones to do. It would take days and days. And when we do this, we can start to see the patterns of tree fall. And that allows

us to see how the tornado behaved as it moved along that tornado path. And around your place, it was quite complicated. There was evidence that this was a multi-vortex tornado. So some tornadoes are just the one vortex, the one circulation, everything's going around in a circle. And it's very simple. In others, there's a number of different smaller tornadoes rotating around a larger area. And when that happens, you start to get things like loops in the damage. So there may be evidence that the tornado kind of went off to the north and looped around and came back down and maybe did another loop a little bit farther along. I saw this on my property where, you know, one pine tree is going one way and then another massive pine tree is going the other way.

And then there's actually a pine tree that's upside down somehow. So I've seen this sort of twisting, you know, sort of trees going every direction on my property. So to me, this felt like a pretty significant storm. Like I've never seen damage like this before. Our neighbors lost their roofs, their sheds, their garages. But sort of in the grand scheme of things, how does this tornado sort of compare to other storms that we see in Canada in a given year? We tend to get a number of EF2 tornadoes across Canada every year.

But a tornado path that's 55 kilometers long and 1.4 kilometers wide, that's something that's more rare. That was a storm. That was a supercell that actually had quite a bit of power. And it's kind of the biggest and baddest of all the thunderstorms. What would the damage from an EF-4 or an EF-5 look like then? It really makes a difference when it hits an urban area. So an EF2 tornado, when it say it hits a subdivision, you'll see several houses with the roof that's come right off. When you get to EF3, it's the roof and some walls that have come down.

And when you get to EF4, there's no walls left standing, maybe just a couple in internal rooms. That's why the advice is to go to a room away from doors and windows near the interior of your house, because those are the rooms that tend to survive even in an EF4 tornado. But in an EF5 tornado,, there's nothing left of the house. It's swept away. And we've only had one five-level tornado in Canada in 2007, and that was the Eli Manitoba tornado. And thankfully, that's the only one we've had. We haven't even had an EF4 since 2018.

So they're very, very rare. So then how much damage then have we seen in Canada from severe storms this year? Well, this year in particular has been pretty bad as far as losses and loss of life and injuries because of the derecho that occurred in Ontario and in Quebec on May 21st. And sorry, what's a derecho? So a derecho is a very long-lived wind event. Basically, it's downbursts and some embedded tornadoes creating a lot of wind damage over hundreds of kilometers. And as far as length and the width is about 100 kilometers.

In the case of the May 21st derecho earlier this year, the damage path is over 1,000 kilometers long. I mean, it basically starts down near Windsor and ends near Quebec City, and then there's even damage in the U.S. on either side of that. And unfortunately, it went through a lot of our most populated areas along the 401 corridor. The insured losses there are approaching a billion dollars. And uninsured losses are usually far more than that.

So this was an extremely expensive storm because it hit all those urban areas. And there have been 12 fatalities that we've tracked down and at least 12 injuries with it as well. Right. So from where I sit, it feels like we're seeing more storms than we did a decade ago. But what have you found in your research? What we found is that there are more impacts occurring from storms, whether it's due to climate change or not. When it comes to thunderstorms, we're not sure.

And so we've started looking at that. I mean, part of what we're doing with the Northern Tornadoes Project is building data sets to be able to look at trends, historical trends, and build a baseline for climate change. But we do have data sets that are fairly high quality in certain regions, and one of them is Southern Ontario. And a paper that I led recently took the Southern Ontario data set that goes back to the 1800s. And we found that overall tornadoes were increasing steadily over that time. But that was mostly due to more and more weak tornadoes being documented and included in the database. And it seems to be a human factors thing where because more people have cell phones, more people are aware of what a tornado is,

we're capturing more events. But when you look at just significant tornadoes, and these are the ones that are EF2 or higher, there's really not much change at all. The other thing we found, though, is that we've noticed in the last couple decades while I've been a meteorologist there's just been anecdotal evidence that it seems that things are changing and we're getting these kinds of tornadoes, these big tornadoes later in the season. That was one of the reasons for doing this study in the first place and sure enough we found that that's the case that instead of these late spring, early summer events, we're getting late summer, even early fall events with big tornadoes. And it's a statistically significant trend.

So it's robust. And what's interesting is when you look at our neighbors that also have long-term data sets in Michigan and New York, they don't have that same relationship. They don't have a positive or negative trend. It's kind of flat there. So there's something special about southern Ontario. And the next step in that research is to figure out what that is. What is it that is special?

Is there some kind of connection to climate change? Right. You said that we're seeing more impacts from these storms. What do you mean by that? That has at least partial explanation through higher vulnerability of society, our dependence on electrical infrastructure, communications infrastructure, and so on. The damage part comes mainly from the fact that the population is expanding, where the cities are getting bigger.

As the cities increase, then you get the infrastructure being built there, and all of that is very costly, even with flooding. I mean, a lot of people are putting in these basement cinemas and spending lots of money in their basement that normally wouldn't have been done that way 50 years ago. A basement was just this leaky thing that you just left alone 50 years ago. But now it's somewhere where you invest a lot of money and when that leaks, then there's all this cost involved. So there's a lot of human factors. There's also just the social impacts as well. We're looking at the Barrie tornado from last year. We actually went back on the one-year

anniversary of the tornado to see how many houses had been repaired to the point people could move back in. And there were still 15 to 20 homes that were unoccupied. And that means there were 15 to 20 families that still hadn't really got back to normal. And there's all kinds of mental health impacts that go with that as well, the stress and dealing with insurance. And I really feel for the people that are affected by these events because it's really hard to get back on your feet again if you've had significant damage. I can certainly relate to the mental health impacts. It's certainly been an emotional roller coaster. And we didn't lose a house or a car or anything like that.

It was just trees. And I can certainly relate. So what happens when storms are later in the season? How does that change the impacts they have or the effects that they have? Well, one thing is that, you know, the perception of tornadoes is that, and for a lot of Canadians, the perception is they don't occur here, that they occur in the U.S. and it's an unusual thing here. And that's one perception we're trying to change. But the other is that it's really a summer phenomenon and it's the summer months you need to worry about. And then once we get into September, tornadoes don't happen. And people just have to be aware of that. And there's other issues such as the sun setting earlier as we get into the fall.

So, some of these tornadoes may be occurring more in darkness or near darkness where it's harder to see them. During the summer, a lot of people are on vacation outdoors, children outdoors, so you can actually see something like a big thunderstorm or a tornado coming, whereas when you get into the fall, everybody's inside and kids are at school. So it gets harder to see those visual cues that let you know that something big is about to happen. We're back in a moment.

How prepared is our infrastructure then to deal with these storms and tornadoes that we're seeing? Well, it's getting better, I think, because more and more city managers and people in leadership positions are realizing the potential for catastrophe with some of, especially flooding and flash flooding. I think there's a lot of work that's going on in cities to try to prepare for these inundations that will come. But as far as being prepared for tornadoes, being prepared for thunderstorms, we've got a long way to go. I've got a colleague, Greg Kopp at Western University. He's the co-founder of the Northern Tornadoes Project with me. And for at least a decade, he's been advocating for these really inexpensive tie downs that connect the roof of a home to the walls of a home. And so, you know, if a home is built with these tie-downs,

then when you get an EF2 tornado, the likelihood that the roof will come off is much lower. Interesting. And then you don't get all of those impacts. A tornado like the Barrie EF2 last year, instead of putting 20 people out of their home, may have put zero people out of their home. There would have been damage, but not that kind of damage. Every year we're getting EF2 tornadoes, so we should be building our infrastructure to withstand them.

Right. And how well does the country do in sort of notifying people in the area that these storms are about to happen? Great. Well, another issue there. We recently at NTP did a performance assessment for tornado warnings that covered the country. And what we found wasn't encouraging. It was about 70% of the tornadoes that we had in our database didn't have a tornado warning out ahead of them. And that included a couple dozen EF2 tornadoes. So even the EF2 tornadoes sometimes aren't getting warnings out ahead of them. So there's a lot of work that needs to be done to try to change that situation, to try to get these tornado warnings out sooner. So there's more lead time or more time for people to react. Having said that,

it's been really great to see the public reception to the alert ready, the warnings coming through on the cell phones. It's gotten to the point now that if people are in an area that doesn't have great cell coverage and they're not getting these alerts in their cell phones, then they're complaining loudly, which is great to see because this is something that is saving lives. If there's a tornado watch issued, you can take precautions by just closing all your windows and doors. It makes a big difference. If your garage door is open when a tornado hits, there's a good chance that the wind will pressurize the inside of the building and you might lose your roof because of that. Yeah. One of our neighbors at our property

told me that they got the notification on their phone and then they went running down into the basement and then they got hit by the tornado. Their house got hit by the tornado just a few minutes later. So yeah, it seems like these could be pretty important. Yeah, we've seen quite a few examples of that now where there's been direct evidence showing that people are taking cover when they get that message. And then, you know, something terrible happens to the place they were just in before they took cover. So, I know for myself, whenever I see sort of, you know, dark clouds rolling in, I kind of get excited. I really like, you know, a summer thunderstorm. But if we had

been on our property when this happened, that when the tornado happened, like we would have been in serious trouble. We were camping in a tent. And honestly, I'm afraid of what would have happened to us if we had been there. So do people like me need to sort of rethink storms? Do we need to think about storms differently, given that we're seeing more consequences from them now? Well, you certainly have to be prepared. Camping is really tough because you're in an area surrounded by trees. A lot of times you're just in a tent. There's not a lot of protection. Personally, when I'm in that situation, I think the car is the safest place, whatever vehicle you have. Number one, because it protects you against lightning. If you're inside of a vehicle,

it acts as what's called a Faraday cage. So if lightning does hit the vehicle, it spreads off the charge and it doesn't affect the people inside. But when you start having things like trees coming down, obviously a car is not going to stop. A tree will make a pretty good dent in a car. But if you're in a car and keeping very low so that you're out of the way of debris, I think you've got a better chance of survival there than if you're in your tent. Personally, that's what I would do. But in general, though, people in Canada tend to have this idea that big storms occur in the

States and we just don't get them here. And through our project, I think we're really having an impact on people's perception because we're showing that, yes, they occur right across Canada. And in the middle of the summer, we can get storms that are on par with anything in the U.S. I mean, our season is shorter, June, July, August, basically, and then it starts to fade out. But during those three months, especially July, anything goes. We could get right at the top of the scale as far as tornado intensity.

David, thank you so much for chatting with me. Oh, my pleasure. That's it for today. I'm Mainika Raman-Wells. Our summer producer is Nagin Nia. Our producers are Madeline White, Cheryl Sutherland, and Rachel Levy-McLaughlin. David Crosby edits the show. Adrian Chung is our senior producer, and Angela Pachenza is our executive editor. Thanks so much for listening, and I'll talk to you next week.