Narrator: In 2022 a Derecho a strong and fast moving line of wind and thunder storms tore across Ontario and Quebec. It knocked out power to nearly a million households and killed 11 people. It also caused around $1 billion in insured damage. Is climate change making historic storms like this more common? Greg Kopp is director of the Canadian Severe Storms Laboratory and an engineering professor at Western University. And Anabela Bonato is the managing director of climate science at the University of Waterloo's Intact Centre on Climate Adaptation.

Anabela Bonato: Yes, thank you for having me, Greg.

Greg Kopp: Great to have you on the line.

Anabela Bonato: Nice to be here. Thank you.

Greg Kopp: All right, Anabela, we're going to start with you. Ontario has seen some frightening storms in recent years. Even on my drive into work this morning, a bit of a storm. I was like, oh, what's happening? Are we actually seeing severe storms and rainfall or is this a perception.

Anabela Bonato: We're having more storms? Definitely. And climate change is one of the main drivers. So we know that with climate change, our average temperatures are rising and for every degree that it rises, the atmosphere can hold more moisture. It can hold up to 8% more moisture. So that moisture is really coming down in a shorter amount of time. A lot of water comes down when a storm comes through. So we're seeing a bit more storms occur, but also just more water falling on the ground. And we had a warning today. There was a flood warning issued for some areas around southern Ontario and a little bit of northern Ontario, just because our grounds are quite full of water right now. Some areas still have snow, so all that rain that's coming down can lead to some flooding.

Greg Kopp: All right, Greg, on the more extreme side of weather, let's talk about winds because this is what you do. You know, tornadoes down sort of down bursts. But also in our lexicon as we're learning more things like Derecho, it just seems like, you know, as we, as we kind of go through time, we're learning more and more about these strong storms. What does the data actually show?

Greg Kopp: Well, these are some of the most extreme storms nature has to offer. The data is showing across North America, Canada and the US that there's not many more tornadoes. There's probably about the same number of tornadoes, but they're changing where they're happening. And for Canada, they're moving. They're shifting eastwards. So instead of having a peak in southern Saskatchewan, southern Manitoba, as it was historically, the peak is now moving into southern Ontario, where we are. And so we're probably experiencing more here in southern Ontario than we had in the past, although overall across the continent there's not more tornadoes. For example.

Greg Kopp: Is the is the perception or the trend that it will we will see more of this in this province.

Greg Kopp: Yeah, we're expecting this this eastward shift. We haven't been able to attribute it to climate change yet, but it's very evident in the data and the transition of the data over the last 30, 40 years. It is kind of the time frame we look at, and we're seeing that change happening.

Anabela Bonato: Anabela, the planet continues to warm. As you mentioned, the last three years, we have had the hottest on record. What does that mean for Ontario's severe storms? When we look at the long term forecast?

Anabela Bonato: Well, we know also that 2026 is looking like it's going to be another hottest year on record and potentially now 2027. So as we look forward, even just in the short term, we should expect to see variations in how precipitation occurs. So we may have more intense rainfall in some areas, but drought and other areas, that's that's the tricky thing about water when it comes to climate change, we think it's all going to go up, but we could actually see more drought. So for example, New Brunswick had drought over the last few months. Their winter was quite dry. So we just don't really know how water is going to hit in the shorter term. I can say Ontario is looking at potentially having a few more intense storms, but a bit more drought just because of that hot climate that we're expecting to have over the next couple of years. But with water, it's really hard to know where it's going to go in the long term. And if we're going to have more extreme precipitation or not, likelihood is, yes, more events where a lot of water comes down will probably go up, but we just don't know exactly where.

Host: So we've already had flood warnings in southern Ontario today, you know, flood warning there. With the real test coming in the summer, a lot of people can remember what, you know, July's of, I think it was two years ago where in the city of Toronto and southwest in southwestern Ontario, where we've seen a lot. I am curious about the watersheds in this province. Are there any watersheds that you're concerned about right now that you're looking at, kind of marked on a map for something that we need to be watching?

Anabela Bonato: Not particularly like that, but certain cities are always higher risk. So 80% of Canadian cities are built on floodplains. So floodplains are where rivers are meant to grow. And what we love about Canada is we say, let's go for a drive to a small city. And usually that small city will have a river running through it. So we've put ourselves at risk. So that means generally, if we're close to a lake like Lake Ontario, all those cities in that area, or if you're close to a river or even where I am from Guelph, we have a river. You are at higher risk of flooding. So we're always looking to those areas. But again, if we're looking at a year where we could potentially experience more warming than normal, I'm more a little bit more concerned about the drought issues. So not enough water happening in those areas.

Host: What's the concern there when it comes to droughts?

Anabela Bonato: Drought can lead to a lot of stuff. Yeah. So it's not great. So of course it can lead to more wildfire risk. Luckily we are getting quite a bit of rain right now in southern Ontario. But as the months shift and if we do move into an El Nino, so we've heard that there's a 61% chance that we're going to shift to El Nino. El Nino tends to bring a bit of drought to the area, so that can increase our chances of wildfire. And we had a wildfire in Kawartha, which is quite close to Toronto just a couple of hours away last summer. The likelihood of that happening again is increasing. So it's something to look out for and be aware of.

Host: Okay. And of course, with fires, even if we're, you know, in an urban centre like Toronto, there is smoke and all of that we have to contend with as well.

Anabela Bonato: Absolutely.

Host: All right. Greg, as a specialist in the field of extreme wind storms and tornadoes, let's talk a little bit about preparedness here in this province. Are you concerned about the lack of preparedness? What do we have in terms of safeguards?

Greg Kopp: Well not much. And so it is concerning one of the peak vulnerabilities in severe storms in severe wind storms is the roof. Our roofs are really strong for holding the snow up. But when the wind comes, it wants to lift the roof up. And we need to hold it down actually. And there's simple things we can do to mitigate that, but we're not doing them yet. And, and so that's where the vulnerability is for people. And it's a life safety threat. If your roof comes off in a tornado that can go down and hit your neighbour's house downwind, and you're also your, your walls are vulnerable to collapse. So that's where the concerns are for real extreme windstorms.

Host: Where is the safest place to be in a, in a home when a tornado is hitting?

Greg Kopp: Well, the basement. And fortunately in Canada and Ontario, most of our homes have basements. And so that's a really safe place to go in a severe windstorm. If you don't have access to a basement, get away from the windows and get to the interior of the house if you can.

Host: So for those, of course, we're in the city of Toronto and major cities, lots of towers, lots of condos, apartments. You're talking get into the centre of the building.

Greg Kopp: Yeah. Get away from the glass. Get towards the elevator core glass when it's under pressure, actually can emit small particles as it as it's stressed. And so there's a danger even if your windows don't break. So get away from the windows.

Host: All right, Annabelle, let's get back to flooding. When we see flooding Ontario. Is it we talk about the watershed. Is it rivers overflowing? Is it sewer systems backing up? What happens when both are overwhelmed?

Anabela Bonato: Yeah, it's a combination. And historically we used to see more river flooding occur. So again our cities are built around rivers. So we can see that happen quite a bit. But over the last few years like the last 15, we're seeing a lot more just urban flooding or what's called pluvial flooding. So flooding from a lot of rain coming down. Yep. Pluvial. Okay. Which comes from a word about rain or it's also talked about as overland flooding. So all of those kind of mean the same thing that a lot of rain comes down because we've built cities with a lot of pavement. The rain has nowhere to go. So it goes into our homes. So we're more and more seeing that and seeing our systems being over flown. And so then the water again has nowhere to go, goes into your home. So it's so important that people prepare everywhere. So even if you're not really close to a river, you're still at risk of flooding just because there's pavement around your home.

Host: When we talk about preparing, what are we doing?

Anabela Bonato: Yeah, there's so much to do. So at the municipal level, ideally, you know, we want to preserve our watersheds. So there's a lot of conversation around what's the importance of watershed. What do they do for us? They slow down water. So that peak time when the water is coming down, it can slow it down, clean it and release it slowly. So ideally we keep those around. But also, if you already have your home, there's already a lot of pavement around you. You can install a sump pump or check if you have a sump pump. Make sure you have a backup battery. So electricity tends to go out with these extreme storms. You want to make sure that's still working. And for simpler things, cleaning out your eavesdrops, making sure that water can flow freely away from your home by also extending your downspouts. So lots of stuff that can be done.

Host: Okay, Greg, in terms of this province, when we talk about tornadoes, the first thing I think about is actually the US. And I think about Tornado Alley where, you know, they have the highest incidence of tornadoes. Do we have a sense you had said that things are shifting here in this province? Do we have a sense of where in Ontario is the most vulnerable? I think a lot of people in Newmarket, in Aurora and Uxbridge have, you know, strong memories of what happened only a few years ago. Do they need to be concerned or what direction are these storms heading?

Greg Kopp: Yeah, well, they're in southwest Ontario. Actually, the peak that we've analyzed is right here in London where I am. We haven't had a big one in southwestern Ontario in a number of years. But statistically, that's where where the most are. And but all of the southern part of the province is, is really vulnerable to it. Since we started the Northern Tornadoes project, we've been seeing over 60 tornadoes a year in Ontario, southern Ontario, and Quebec, which is quite a lot more than one really thinks about with tornadoes. So that vulnerability is growing and it's also growing because as our population grows and we spread out over the land, we're covering more of the space. So so we just have more vulnerability from those two things. The changing pattern and population growth.

Host: With that being said, Greg, if there was one thing you could do, wave your magic wand, let's say that would better prepare Ontario not just on an individual level, but from a provincial lens to deal with severe storms and extreme weather. What would it be?

Greg Kopp: I would change the building code. I would change the way, the way we build our houses just to make them safer. It actually is really cost effective in new construction. It's a few hundred dollars to $1,000 to make it resilient to tornadoes. And, and we hold the structure in place with that. And so we think that's a really good investment for, for, for Ontario. And so we'd recommend changes to the building code.

Host: All right. Anabela, if you had that magic wand, if there was something that you could do to help prepare Ontario for these storms, whether it's in the short term or the long term, got housing, that's one. Is there something else?

Anabela Bonato: Can I waive it and get two wishes?

Host: Sure. For sure.

Anabela Bonato: Go for it. The first one would be building away from floodplains. So let's no longer build our infrastructure, homes and roads in the areas that are meant to flood. With that being said, also let's invest more in our nature based solutions. So that would be my wish. Number two. So as I mentioned, you know, wetlands are doing the job for us. There's so much cheaper for us to maintain. It's natural. We love to be around them. We can build walks around them so that people can use them as well. And they absorb about 38% of flood waters when they go through urban areas. And we have those wetlands available. So those would be my two things that I would ask for.

Host: All right. I think that's a great point to leave off on Greg. Anabela, really appreciate it. Thank you so much.

Anabela Bonato: Thanks for having me.

Host: Thank you.