Why Canada's Forest Fires Are So Difficult to Fight

[00:00:00][music] [music] >> Brian Lehrer [music] on WNYC. You know, there's been so much health and climate news this week that we're devoting 3 days to it. We usually set aside a segment on Tuesday to do something health and climate related, health or climate related sometimes, to make sure that those stories don't get lost in the crush of other day-to-day headlines, but there's so much this week that we're doing a Tuesday health and climate segment, a Wednesday one today, and a Thursday one tomorrow.

[00:00:41]Today, a two-part deeper dive into the connection between forest management and global warming.

[00:00:49]And part two, how to read the air quality index and protect yourselves the next time the smoke comes back. Part one, as smoke from Canada's wildfires filled the Northeast and Midwest air last week, President Donald Trump blamed Canada.

[00:01:05]>> You know, we got to stop the fires up there. If we can help them, we'll help them.

[00:01:09]But maybe they should pay us some damages or something, or we should do some tariffs.

[00:01:15]>> We should do some tariffs, or they should pay the United States for the damage that's being done because these wildfires originate in in Canada.

[00:01:27]This wildfire management charge, you may remember, is similar to what he leveled at California's state government during past fire seasons. Mismanaged forests, rake the leaves, things like that. What conservatives tend to leave out is the role of a warming climate, but both things can be true at once, right?

[00:01:47]Forest management matters, and climate change is making fires bigger, longer, and fiercer. So, what actually makes forest management so hard to change?

[00:01:57]What, if anything could Canada have done differently or do differently in the future? And how does managing a forest have to change when the climate is changing, too? Joining us now to walk through some of the science is Augustine Bigot, assistant professor in the Department of Mechanical and Aerospace Engineering at NYU Tandon, where [snorts] um he uh runs the Ignite Fire Research Lab and studies how wildfires start, spread, and can be predicted. Professor Bigot, welcome back to WNYC. Thank you so much for joining us.

[00:02:33]>> Good morning, Brian. Thank you so much for having me.

[00:02:35]>> So, in general terms first, and we'll get into specifics later, the president says Canada's fires come down to bad forest management. Canada's prime minister points to climate change. As a researcher in the field, is this an either-or situation, or is the real starting point here how those two forces feed each other?

[00:02:56]>> Well, I think that the the there's a bit of both, of course. Now, one thing we want to bear in mind first is that Canada is a very sparsely populated country. And so, we have roughly, you know, 40 million people over, you know, 10 million square kilometers. And so, for the audience in New York, the density of Canada is such that you roughly would have, you know, 200 people over a surface the size of Manhattan.

[00:03:23]And now, imagine that it's summer, and it's getting pretty hot, and and you're roughly 200 people over such a large area, and a fire starts somewhere. You know, you can try to manage the land as well as you can. There are going to be areas that are not going to be accessible. And so, first, I I really want to emphasize that point. Canada is a large area of natural land with very limited inhabitations. And so, and so, if we consider fire in that context, fire is part of the natural ecosystems.

[00:03:51]And so, we expect some forests to burn as part of the natural life cycle. So we have a regeneration of the land. Some of the trees that may be sick or dying are burning in the flames. New sprouts can come off the ground. And so we have a healthy ecosystem that is sustained with the presence of of fire. And so that's that's really our first point here. Now, when we have inhabitants and when we develop policies to manage lands, we try to develop policies first to protect assets. And we want to protect our homes. We want to protect our highways.

[00:04:24]We want to protect our power plants. And so very close to where people live and and where where industrial activities are present, we're going to clear the land and we're going to do this for instance mechanically. We're going to use bulldozers to create some clearings.

[00:04:39]We're going to try to increase the access to firefighters with more roads.

[00:04:43]We're going to put water potentially reservoirs or accesses. And that's going to protect us as as a last line of defense. And what I think is important to remember here is that we're going to protect some areas from wildfires, but we're not going to completely extinguish wildfires. And so there is policy there are policies in place to do this, but they're not going to cover the very large and immense land of Canada, which again is the size of the US, but it's roughly, you know, 1/9 of the population.

[00:05:15]>> Right.

[00:05:16]I mean, people in the New York area, for example, really have never experienced these kind of smoke days until a few years ago. Now they seem to be a regular thing each summer.

[00:05:29]Are these smoke conditions that travel all the way down here becoming more frequent or more intense because of global warming?

[00:05:39]>> Global warming is going to play a role.

[00:05:41]And first, back to these ecosystems, because of global warming, the forests are going to have to adapt. For a lot of these places, what it means is, you know, drier conditions, warmer and longer summers, and so for some of the plants and trees, that's going to mean that they're going to they're going to extend or they're going to go beyond the area in which they can survive. So, you're going to have a lot more dead trees or a lot drier vegetation, and that's more likely to catch fire. So, we are likely to see a lot of these very big fires happening because of of global warming. Um this means that you're going to have more sources because in a place like Canada, because of the atmosphere, there's going to be more lightning. And in Canada, lightning is the number one cause of of wildfires uh in terms of the the size of the area burned. And then, you have a drier vegetation at the bottom of these lightning. So, you have a bigger fire very rapidly. Now, when you have a relatively small wildfire, you know, the smoke remains contained.

[00:06:38]We've done a a study uh at NYU where we were looking at the impact of the smoke.

[00:06:44]And so, a PhD student, Josh Lee, was looking at the correlation between areas where the air quality becomes bad and the size of wildfires. Uh and one of the findings we had which was very interesting is that for relatively small wildfires, of course, the closest area are the most impacted. And when the fire turned to the size of the mega fires we're seeing today in Canada, it's actually more of a donut shape. And so, what I mean by this is that the fire is so large, it's spewing all the smoke very high in the atmosphere, and this smoke is going to be able to travel hundreds, if not thousands, of miles all the way, for instance, from Canada to the US uh eastern coast uh and to finally create untenable conditions uh in places like New York.

[00:07:27]>> Interesting background. Listeners, anybody out there right now who's involved in forest management of any kind and have a take on what needs to be done differently in the era of global warming? Obviously, we could talk about how to prevent global warming and cutting down on fossil fuels and all of that. Um that's kind of a a given, at least on this show, that that needs to be dealt with seriously. Now we're talking about how these two things interact, global warming and forest management to avoid the kinds of hazardous smoke conditions, which are becoming more common in more places as they intersect. 212-433 WNYC. Seriously, anybody in the field that realizes there are not a lot of foresters who live on the Upper East Side or in Bensonhurst or wherever you are in our area, um but maybe there are some. Uh or anyone else with a question for our guest, Professor Gribou from NYU, who studies this. 212-433 WNYC. 212-433 9692.

[00:08:35]Call or text. You know, Professor, the other thing that I hear frequently um from the president and from from others on the right primarily is that environmentalists have become so married to what they might see as a sentimental notion of forever wild in forests, certainly as pertains to California, they would say, maybe Canada, too, that they aren't undertaking things like controlled burns at different times during the year or clearing brush even, um because they want the forest to be untouched by human intervention.

[00:09:18]Is that an issue as you see it? A legitimate issue to any degree?

[00:09:22]>> Well, it's a very interesting question.

[00:09:25]Uh but before before I I I answer this, I just wanted to point out something for our New Yorkers who are listening to the show. Uh there may not be a lot of foresters, as you point out, on the Upper East Side, but there is very close to New York an amazing area. It's called the Silas Little Experimental Forest and that's in the Pine Barrens in New Jersey. And there the US Forest Service is doing an amazing set of research and part of it is around understanding better the behavior of wildfire and questions of of smoke for instance.

[00:09:59]>> And that's good. And you know, I was just talking cuz I know that certainly in our listening area, we have the Catskills, we have the Adirondacks, uh we have the Berkshires, we have the White Mountains and the Green Mountains in New England. So, uh uh you know, anybody involved with forestry in in any of those areas, all of which I consider our region, feel free to chime in, but Professor continue.

[00:10:21]>> Exactly. And now when it comes to control burns, I think it's a very interesting question. So, so for our for our audience, the whole idea of a control burn is to say that if, you know, today in July a fire starting in Canada can have dramatic consequences, well, maybe if we start that fire, you know, right after the snow just melted or just before snowfall, we may find ourselves having, you know, wildfires that are in wetter environments, in a colder climate. So, they may not have the same, you know, fire size. The flames are going to be shorter, it's not going to release the same amount of energy, and so we have a more controllable fire. And so the whole idea is to say, well, maybe if we give a little help to nature, we can decide when and where fires are going to spread.

[00:11:11]Historically, we've always operated like this. If you think about how either native populations, but also colonizers clearing land for pasture and grazing have worked, the humans want to decide when the fires are burning on the land. And then it's nice to have a certain degree of control. And I'm setting I'm saying a certain degree of control because we have seen quite a few control burns become uncontrolled wildfires, unfortunately. So, a lot of precautions need to be taken. But, my point here is that we can provide the initial fire source, and then nature is going to respond. So, I don't think it's such a problem to create control burns. Again, the issue that we have then is sometimes an issue of responsibility in that if we start intentionally a fire, we can assume that we are bearing the consequences of that fire. And so, that's very different from lightning.

[00:12:06]>> And by the way, sorry Pennsylvania, I left out the Poconos on the list of forests in our region. Hello Stroudsburg and all the other places around there.

[00:12:15]Your Your own research, as I understand it, says that most wildfire prevention models treat forests as if they're frozen in time or static. In the International Journal of Wildland Fire, you write that vegetation, quote, works on a time scale that's different from climate or weather. Explain that and why it's a problem.

[00:12:37]>> Uh with pleasure. So, we recently published some work in which we were looking at medium-to-long-term wildfire risk. And what I mean by this is that we're trying to figure out today, in 2026, what is the wildfire risk going to be like in, say, 2050, 2060, 2070.

[00:12:56]Now, we're talking about a certain time scale when we want to project ourselves several decades in the future. And for our audience who, you know, may have a few decades of age, you understand that there's going to be changes in the climate conditions, unfortunately. And there's also going to be change in vegetation. And the systems are dynamic.

[00:13:19]So, today weather is something that changes, you know, on a hourly basis. It may rain now or be sunny in an hour.

[00:13:26]Climate is something that changes more on a year-to-year basis. We're seeing the average temperatures rise. We see changes in rain patterns, for instance, and vegetation responds at a slower time scale. So, a tree is going to grow over some decades. Brushes are going to come out of the ground and grow and maybe die over similar time scales. And so, the research we did was to try to understand how these different things are coupled together.

[00:13:51]Today, if we do predictions of wildfire risk in 2050-2060, the most common way of doing this is to pull models that scientists have developed around the globe to understand what the climate conditions are going to be like in 2050 and 2060 and apply these weather conditions on today's vegetation. So, we're basically assuming that the tree that is here today in 2026 is the same tree that's going to be present in 2050-2060.

[00:14:19]Now, our assumption is that this tree may still be here, but if the conditions get too hot, too dry, too wet, if there's any human intervention, you may not find the same tree at the same place. You may have invasive species that are progressing, and we see this all over the country and all over the world. You may have some fragile species that disappear as well, and you may have also some natural phenomena like epidemics and insects or locusts that can, you know, remove some vegetation in different parts of the world. And so, what we did is develop a coupled model where we're looking year on year how the climate evolves and how the vegetation responds to that.

[00:15:01]Now that we have updated maps of vegetation, we can predict the wildfire risk by looking at the three major components of the wildfire risk. The first one is weather, so the short-term conditions on a day like today, what's the temperature, how humid is it, what are the wind conditions that we expect.

[00:15:20]We take into account the vegetation conditions. Do we have grasses? Do we have brushes? Do we have trees? What kind of species and how dry are they?

[00:15:28]And finally, the topography. So, what is the slope? What is the altitude, for instance? Topography is of course something that's not going to change in the next few decades. We don't expect to see a new mountain ridge appear between your listeners in Pennsylvania and the other ones in the state of New York. And so, this is something that we can consider as static in our model.

[00:15:47]>> You know, for all the um forests and mountain ranges that I cited a few minutes ago, we are getting one actual employed forester calling in. And who does he work for? The city of New York. Marshall in Brooklyn, you're on WNYC. Hello, Marshall. What do you do?

[00:16:08]>> Uh I'm a forester for Brooklyn Borough Forestry at the NYC Parks Department.

[00:16:13]>> And >> Uh well, I had also respond Well, I used to work in Manhattan, but I had responded to the Inwood Hill fire back in I believe it was the fall of 2024.

[00:16:25]And so, I got to see an urban wildfire firsthand. And I think that we have to consider not just uh like rangeland wildfires as the guest is speaking about, but also urban wildfires cuz there was the big one in Prospect Park and on up in Inwood Hill.

[00:16:41]And I think the city is moving towards developing some type of system for response, but I think we need to consider those questions a bit more deeply about how we manage wildfire how we manage fire and fire ecology in urban spaces.

[00:16:55]>> Even uh urban forests, Marshall, are they producing the kinds of high AQI smoke conditions that these fires coming down from Canada are?

[00:17:08]>> No, there's just not enough wood to produce that. Um like the forest we have in the city, while very important to the air quality of the city are nowhere near the scale of the Canadian boreal like you know conifer forest that are millions upon millions of acres large whereas our acres only measured in the hundreds if at all thousands.

[00:17:32]>> Marshall thank you for your call we really appreciate it. Here is Sunny calling from New Mexico. You're on WNYC.

[00:17:38]Hi Sunny.

[00:17:40]>> Uh good morning.

[00:17:42]Uh thank you for taking my call.

[00:17:45]My question is to um one Brazil is like considered the lungs of the earth with their rainforests.

[00:17:53]So with the vastness of the forests in Canada can they sort of also be considered like lungs of the earth?

[00:18:01]>> Oh that's a great question.

[00:18:02]>> need to breathe.

[00:18:04]And then >> Oh go ahead you had a second part. Go ahead.

[00:18:08]>> Yeah. The second question is um was the Canadian fires nature caused or man caused?

[00:18:16]And then I think the third one is more of a comment is like um I think we need to have a better assessment of smokes coming from wildfires because I notice in New Mexico we get a lot of smoke from surrounding wildfires like in California you know Utah etc. etc. And the I don't want to call it quality of smoke but it seems like when they are near man made um cities the smoke quality is worse.

[00:18:54]And then if they're just like burning wildfires the smoke quality seems to be less abrasive on my lungs um and I have asthma.

[00:19:08]>> Huh. Sunny thank thank you for three really interesting and important questions. Our second guest in this segment is going to be a physician specifically on um the smoke and I'll pose you a question about the the quality of the smoke and smoke assessment as you put it. Uh but for our current guest, her first two questions, can we call Canada's vast forests the lungs of the earth like we do often hear as she says Brazil's rainforest referred to?

[00:19:41]Um and and uh and then we'll take the second one.

[00:19:46]>> Well, thank you. Thank you so much for calling. Um this is a very interesting idea to call to call this forest a lung of the earth. I had never thought of it this way and I think it's because like everyone else, I mostly hear about the Amazon as as a lung of the planet. Now, if we take a moment to try to understand that concept, what we mean by lung is that it's taking carbon out of the atmosphere and it's rejecting oxygen.

[00:20:13]And so for the Amazon, we can clearly see when we look at the concentration of these gases that there are you know, pretty large amount of carbon that are absorbed and and amount of oxygen that are generated in that area. I don't know these maps for Canada, so I'm not going to speak about something I don't know, but what is sure is that the size of the boreal forest in Canada is such that a lot of carbon that could be in the atmosphere has actually been sequestered inside the wood and and the pines pine needles and the leaves that you can find in that area. So there is a certain you know, lung of the earth happening over there.

[00:20:54]>> And the New York Times reports that half of Canada's fires burn in areas so remote they can only be reached by plane. Sometimes they are just left to burn for that reason. So when land is that inaccessible, how much management is even possible?

[00:21:10]>> I think that when we get that far from human settlements, you know, we we have to accept to a certain extent that nature is going to drive the mechanisms.

[00:21:19]And so, we can try to have a very, you know, light and and targeted modification of the landscape. We can try to import certain species. We can try to sustain the development of certain plants, for instance. But, it's going to be very hard to have any intervention once the fire starts. I do remember one of my colleagues, for instance, working with Russian scientists in Siberia, who were telling him that, you know, most of the fires they let them burn because even with the helicopters that they have in some cities, the helicopters would run out of gas before they reach the fire. And so, you really get in such a remote area that most of the practices we see close to our cities become irrelevant.

[00:22:03]>> And I guess, yeah, that makes um prevention harder, uh other than at the level of just reducing the conditions, um meaning getting a handle on global warming. But, her other condition our other question was whether the forest uh the forest fires in Canada that we're talking about are from natural causes or human causes. Is there a general answer to that?

[00:22:31]>> There is. So, so there are statistics that are reported at the national level, and I think it's interesting to have a comparison. In the US, we attribute roughly 85% of our fires to human behavior. So, it can be an accident, like a discarded cigarette butt, an unextinguished campfire, or, for instance, a power line falling on the ground. And the last 15% are roughly attributed to natural causes.

[00:22:58]Fortunately, arson is a very tiny fraction of the total number of fires that we see.

[00:23:04]In Canada, that fraction is slightly different. We see about half of the fires being caused by lightning, so natural causes, and half of the fires being caused by uh accidents and human behavior. What is interesting to consider is that naturally accident caused by humans happen in the vicinity of our communities. And so they're usually extinguished pretty rapidly.

[00:23:27]In contrast, lightning can happen anywhere. And it's going to happen in a very distributed way across the country, very often in those remote areas we just talked about, where you know you can barely access it if ever. And so those lightning fires in Canada are responsible for the vast majority of the area that is burnt.

[00:23:47]>> Last thing before we transition to our second guest, an environmental health physician, to talk about managing the smoke conditions, managing your own health in the smoke conditions when they return.

[00:23:59]Um but for you, Professor, listener writes, "I'm a firefighter in Putnam County. Even managed forests will burn when dry and hot. Firefighters no longer have off-seasons to possibly conduct controlled burns. With global climate change, the fire season is now 12 months a year. And they continue in Ontario with 1.8 million acres in fire, they need support. People, power, money, and resources, not pithy blame and stupid tariffs, which just suck up needed resources and make everything worse for everyone." Obviously talking back to President Trump. Uh a comment on that and then we're out of time.

[00:24:41]>> Uh yes, so maybe I'll make that comment on on two points. Very rapidly, I would focus again on the first part of what the president said when he starts by saying we should help them because fires are not a national problem, they're not going to be solved by tariffs. It's an international collaboration that's needed, so I think that's really trans border approach that needs to be adopted. And the second one is around this question of resources. To give an idea to our listeners, today in the US, there's roughly 61,000 hectares burning. So, that's about 120,000, you know, football fields, if you want. And with something like that, it means that the total number of personnel we have, it's roughly 20,000 fire fighters being deployed today in the US. It means that each of these firefighter would have to single-handedly extinguish six football fields on fire. And that gives an idea of the scale of what we're talking about. It is not >> And so, if Trump says Canada should maybe pay the United States in damages for, you know, the effects of of the smoke that's coming down here, maybe the United States should be paying Canada for the much greater global warming load, carbon load that the US contributes than the smaller country to our north.

[00:25:58]>> The The finger pointing is is an exercise that never ends. So, so that's something I would agree on with you, yeah. That's >> I guess then we go, assistant professor in the Department of Mechanical and Aerospace Engineering at NYU Tandon, where he runs the Ignite Fire Research Lab, and studies how wildfires start and spread. Thank you so much for joining us. We really appreciate it.

[00:26:23]>> Thank you, Brian.

[00:26:25]>> Brian Lehrer on WNYC. Yeah, part two with that environmental health physician right after this.

[00:26:32]>> [music] >> Brian Lehrer on WNYC. [music] Now, we'll get a take on the health effects of wildfire smoke and how to protect yourself when it comes back, which we are told it likely will before the end of the month. Here to answer my questions and yours is Rebecca Floor Shine, an environmental health physician at the NYU Grossman School of Medicine.

[00:27:01]Dr. Floor Shine, thanks for sharing your knowledge about this with us. Welcome to WNYC.

[00:27:06]>> Thank you. Thank you for having me.

[00:27:08]>> And listeners, your questions are of course welcome about wildfire smoke, the AQI or air quality index that's become a more you know, common part of the weather forecast, unfortunately. How to protect yourself when the air is bad or anything related 212-433 WNYC call or text 212-433 9692.

[00:27:32]So, Dr. Floor Shine, what is wildfire smoke? What kinds of particles are in the wildfire smoke?

[00:27:39]>> Uh so, wildfire smoke is a combination of carbon particulate matter, carbon monoxide, and anything that's in the forest burns up in it. So, the major component of it is something called particulate matter, which I, you know, when I teach and give my lectures call air garbage because it really is a non-specific term just to describe small particles that could be make up made up of anything.

[00:28:08]Um but the issue with particulate matter is not 100% just what's in it, but it's it's the size.

[00:28:15]Because as particulate matter gets smaller and smaller, it's able to make its way into our airways when we breathe it in, and particulate matter that's about 2.5 microns or smaller can make their way all the way down into the lungs and cause disease and symptoms in the lower airways. And then the particulate matter that's even smaller than that, which we call nanoparticles, can actually diffuse directly into the bloodstream and cause symptoms and inflammation in different ways.

[00:28:43]>> Can you give me an example of that because people can at least relate to the fact that they might be coughing or choking or whatever, uh you know, from the smoke getting into the lungs, uh short-term uh effects.

[00:28:56]But, what happens when these tiny particles get into the bloodstream?

[00:29:01]>> Uh they just they have a a variety effects, but mostly are just very inflammatory and they they can cause systemic issues. Um so, that's why, you know, one of our more vulnerable group vulnerable groups during uh one of these wildfire events is our uh older individuals and people who have underlying heart disease because you do get that systemic inflammation that's associated with inhaling the smoke and the particulate matter that's inside of it.

[00:29:27]>> Interesting. Why older people if they are not smokers and let's say otherwise healthy? What happens as an otherwise healthy lung ages, if that's the right question?

[00:29:38]>> Well, it's it's not always uh the the lung disease that's the problem. So, uh when you have when you have uh somebody who um just is is older and has less resilience overall, um those individuals uh who have the inflammation that's associated uh with uh inhaling all this particulate matter, um they're going to get sicker. So, if they have underlying heart disease that's been sort of flying under the radar and then all of a sudden uh they're having some respiratory distress, they're stressed overall, um and then you have this inflammatory response that's associated with um inhaling all this particulate matter, that's what can tip uh a lot of people over the edge um with regard to having symptoms from their heart disease.

[00:30:29]>> So, that's why >> earlier, uh and that's very clear. Thank you for explaining it so clearly. We had an earlier caller who said she has asthma.

[00:30:39]Um what about people with asthma or other chronic actual lung conditions?

[00:30:45]What happens to them in the conditions of these high AQI? And we'll get to AQI and what it actually means. But these high AQI smoke days.

[00:30:55]>> So, one of the things that's interesting about asthma is it's it's one of the few diseases where patients actually feel their symptoms on a daily basis, right?

[00:31:04]And we can't really say the same thing about heart disease or diabetes or high blood pressure.

[00:31:09]But our asthma patients always know when the weather changes. They know when it's a high pollen day. They know, uh, you know, when the when the weather's been too hot or too cold because they they feel it in their lungs. And we see the exact same thing uh, with regard to, you know, these these wildfire events. Um, and that's why, you know, I work at the at the Bellevue Asthma Clinic, um, here in New York City. We always make sure that our patients are prepared for events such as these. Uh, if there's a heat wave coming or if we know that there's going to be, um, high pollution days, making sure that patients who have asthma have their inhalers or preventive medications ready uh, before the event is really important. Making sure that they have their emergency prednisone, which is a, you know, medication that patients take for asthma exacerbations. Making sure that they know how to contact their physicians, where their nearest nearest emergency department. All of that is so important because we see, um, that exacerbations go up, uh, very very significantly, um, when these events happen, when we have when we have high pollution days. Even this last heat wave that we had, or excuse me, this last wildfire event, um, last week, we saw compared to the day prior to the smoke that emergency room room visits for asthma went up by 31%.

[00:32:25]>> Mhm.

[00:32:26]>> Um, and so it's it's tangible in terms of the mother the the numbers that are, uh, recorded by the health department, but also in terms of what our patients tell us in terms of their symptoms.

[00:32:38]>> What do the AQI numbers mean? Cuz when it's 50, which is the threshold where it goes from good to moderate, it doesn't make the news. But when it gets to 150 as it did last week, or even higher, uh then they say hazardous for sensitive groups, and then hazardous generally.

[00:32:57]So, what do these numbers actually measure?

[00:33:01]>> I don't know that I would I would read so much into the numbers uh specifically because they're talking about uh risk at the population level.

[00:33:09]But overall, so the AQI, um it's reporting that at least one of the criteria air pollutants is high.

[00:33:17]It's not always the same criteria air pollutant. So, the Backing up a little bit, the criteria air pollutants are the specific pollutants that have been identified um by the EPA as being specifically high risk for human disease. So, they they're what I call the plonks. Uh your particulate matter, which we just talked a little bit more about, lead, which is no longer really an issue uh since we took it out of gasoline, uh ozone, your nitrogen dioxides, your carbon monoxide, and your sulfur dioxide, which is also uh much less of a factor these days compared to uh a couple decades ago. So, when any of these, uh and it can be a different one on a different day, is is higher than average, um that can affect your air quality. And so, your your AQI gets affected when any of them is is out of order. Um when you go into those unhealthy, very unhealthy ranges, depending on, you know, which website you're looking at that's reporting the numbers, um you know, it is a warning that anybody who is a particularly vulnerable person should be on high alert, like I said, making sure that they have all their medications ready, making sure they they have the capacity to not leave the house uh until weather conditions improve, um you know, that they should consider, you know, putting on uh a properly filtering mask.

[00:34:36]>> Yeah.

[00:34:36]>> Uh, if they have an air purifier, that's the time to to fire it up. Normally, um, we we'd tell patients and and, um, you know, people who are interested in this type of thing that, uh, outdoor air quality is much better than indoor air quality. And so, on a normal day, we actually advise our patients to keep their windows open, uh, as much as possible. But, on a poor air quality day, that's when we say, you know, shut your windows, turn off your turn on your air purifiers, and, you know, do anything that you can to reduce your exposure and reduce your risk.

[00:35:05]>> And, you know, I think Tony in Sturgeon Bay, Wisconsin, has a question about exactly that. Tony, you're on WNYC.

[00:35:12]Hello.

[00:35:14]>> Thanks, Brian.

[00:35:16]50 years in the ventilation business, I've dealt with indoor air quality as my whole life issues.

[00:35:22]Isn't though the chemicals that are in the outdoor air and the particulates the same air that's in our house? And, will a MERV 13 filter filter out the sizes of particulate, um, that we're breathing in our homes?

[00:35:42]>> Great question. Isn't the indoor air just outdoor air that has entered through small cracks in the window or whatever?

[00:35:50]>> Um, that's a great question. Uh, a couple of comments. First of all, I just want to, uh, give a shout out to Wisconsin. I'm from Milwaukee myself. So, very nice to have the opportunity to talk to you a fellow Wisconsinite.

[00:36:02]>> big time in these smoke events.

[00:36:04]>> Absolutely. Absolutely. There's there's no there's no hiding from this. Everyone in the country, especially on the northern half, gets affected by them.

[00:36:10]And it's it's really unfortunate. So, uh, yes, for the most part, um, the outdoor air and the indoor air on under normal conditions are similar.

[00:36:22]Um, a little bit of a difference because your indoor air is going to have more, um, dust mites, um, higher levels of, of, um, dust-related, uh, exposures and triggers. Um, and you get a a little bit more, um, microplastic dust, um, from our furniture and our fabrics, uh, indoors compared to outdoors. So, it's there's, you know, some subtle differences, but, you know, when you're think thinking sort of more high-level from a bird's-eye view, yes, uh, the air quality is, um, certainly similar and the components of the dust that we're breathing outdoors and indoors is is similar. Usually, uh, the indoor dust is just more highly concentrated though than your outdoor dust except when you have these extreme weather events, uh, where the normal barriers from outdoors to indoors do help to sort of provide, um, a barrier or somewhat of a filter.

[00:37:17]>> And certainly, I'm sure many people experienced, as I did, walking from my apartment outside, uh, that particular day last week, it was like, "Whoa, it smells like smoke out here." And it didn't, you know, in my home. What can air conditioning do or not do during a hazardous smoke condition?

[00:37:39]>> Well, that's an interesting question, uh, and it depends, I would imagine, and and perhaps, um, you know, our friend was from Wisconsin who who works in this field would would have some insight, but, um, one of the things that can really exacerbate, um, the air quality issue is exposure to heat.

[00:37:55]And so, that is part of the reason why in the public health space, we really encourage everybody to either have, uh, personal access to air conditioning and also, if you don't have that, to at least know where your nearest cooling center is.

[00:38:09]Um, air air conditioning itself, um, depending on on its effectiveness, can can help to to cleanse and purify the air and also to reduce humidity.

[00:38:20]Uh, the water vapor itself is also a component of, um, um, of of air quality. So, the the more we reduce, uh, water vapor indoors, uh, the more we're we're doing to reduce, uh, symptoms and potential exacerbations of underlying disease during these events.

[00:38:37]>> One more call. Kristen in the West Village, you're on WNYC. Hi, Kristen.

[00:38:43]>> Hi, thank you, Brian, for doing this segment. I'm really grateful that you're doing it. Um, my question is regarding ozone.

[00:38:50]Uh, I'm really also grateful that the, uh, app that I have, I I think it's called Air One or something, um, shows ozone levels and I'm I have bronchiectasis and I'm particularly sensitive to ozone and I'm just wondering how can I protect myself because I understand that, uh, N95 masks only filter out particulates and not gases.

[00:39:15]Um, I have put sheets of carbon filters in my window air conditioners.

[00:39:22]Uh, I'm just wondering if you have any more ideas.

[00:39:26]>> Doctor, do you?

[00:39:27]>> Yeah, absolutely. So, ozone is, um, one of the most interesting criteria air pollutants because it isn't something that is formed and released directly from our from our emission sources. It's something that is derived indirectly when nitrogen dioxide is released into the atmosphere and, uh, interacts with sunlight. Um, and actually those that combination produces the ozone, but you see this, uh, interesting competitive inhibition with nitrogen dioxide and ozone. So, ozone, um, you'll see high levels of nitrogen dioxide near the sources of emission.

[00:40:05]So, when you look at the maps, you see really high levels in Midtown and, you know, areas of of high traffic congestion, uh, in and around New York City. Ozone you will actually find in higher levels in the suburbs.

[00:40:18]Um because you don't have nitrogen dioxide um that's being emitted from vehicles um competing with it. So, if there's somebody who's truly truly sensitive to ozone, um actually being in an urban environment uh is safer that for that individual um compared to being out in the suburbs. Um you know, if you want to get really granular about it. Um but also you want to be mindful of the time of day that you're um you're going outdoors because um when after prolonged exposure to sunlight, that in general is when you're going to see higher levels of ozone. So, um you know, mid-afternoon or early evening, late afternoon, those are going to be the times when ozone levels are highest. Um and also just in general during the summer, ozone levels increase because the exposure to sunlight um overall is increased. So, the caller's absolutely right. You cannot filter out ozone. Um There are I believe there are some uh air filters indoor air filters that can reduce levels. There are certainly uh indoor air filters that produce ozone.

[00:41:22]So, if you have indoor air air filters, um you really want to make sure that you're the one that you have is not ozone producing.

[00:41:29]>> Mhm.

[00:41:30]>> Um but other than that, your lifestyle modifications and just, you know, your timing of exposing yourself to outdoor air is really the best thing that you can do to reduce your uh exposure to ozone.

[00:41:40]>> Rebecca Floor Shine, environmental health physician at the NYU Grossman School of Medicine. See, we didn't even have to check if you were in plan or sitting in anybody's waiting room for an hour and a quarter past our appointment time or only spend 5 minutes with you because that's all the insurance company will reimburse. We We really appreciate the generosity uh of your time and all the the really clear information that you gave us. Thank you very, very much.

[00:42:08]>> Thank you. It was a pleasure. Thanks for having me.

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