Think Out Loud

PSU professor suggests ways cities could adapt to hotter temperatures

By Julie Sabatier (OPB)
Aug. 12, 2021 8:37 p.m. Updated: Aug. 13, 2021 8:47 p.m.

Broadcast: Friday, Aug. 13

Christy Wilding of Portland stayed overnight with her two dogs at a cooling center at the Oregon Convention Center  in Portland, June 28, 2021. The cooling center provided water, snacks, meals, blankets, and cots or mats for sleeping.

Christy Wilding of Portland stayed overnight with her two dogs at a cooling center at the Oregon Convention Center in Portland, June 28, 2021. The cooling center provided water, snacks, meals, blankets, and cots or mats for sleeping.

Kristyna Wentz-Graff / OPB


Vivek Shandas is a professor of climate adaptation at Portland State University. His research shows that how people fare in heat waves varies greatly depending on where they live. According to Shandas, some low-income neighborhoods in Portland are more vulnerable to extreme heat because of the way buildings are constructed and configured as well as what surrounds them. If there’s more asphalt than trees, for example, that makes for even hotter temperatures during a heat wave. We talk with Shandas about what he found when he looked into the dozens of deaths that occurred during the extreme heat in June, and what we can do to create more resilience as heat waves continue to impact the region.

This transcript was created by a computer and edited by a volunteer.

Dave Miller: This is Think Out Loud on OPB. I’m Dave Miller. The historic severity of the heat in Oregon this summer may have surprised many people, but Vivek Shandas has not been surprised by the effects of that heat or the neighborhoods that have been most affected. Shandas is a professor of climate adaptation at Portland State University. In research going back a few years now, he has found that how people fare in heat waves varies greatly depending on where they live. In particular people in low-income Portland neighborhoods who are more likely to be people of color are more vulnerable to extreme heat. As we deal with yet another heat wave right now, we’ve invited Vivek Shandas back on the show to talk about these increased dangers as well as the steps governments can take to address them. Vivek Shandas, welcome back to TOL.

Vivek Shandas: Thanks, Dave. It’s good to be back.

Miller: So during the last heat wave, you went around with a thermal camera [with] various very sensitive temperature gauging devices, to get accurate temperature readings in various neighborhoods around Portland. Have you done the same thing this time?

Shandas: I did. In fact, I just went out the last couple of days. It’s become kind of a casual hobby now, more so than a systematic research project. Because it really is surprising to me each time I go out, how different forms on the landscape mediate this sun solar radiation, which is coming down really hard the last few days, as well as that big heat dome that happened in late June. So I did go out and found some really interesting results in that inner industrial area, which is where (inner southeast industrial area) I spent most of my time in the last couple of days.

Miller: So what most stood out to you this time?

Shandas: It’s really interesting. I was thinking a lot about intersections, like the built environment. I kind of find myself at this intersection of kind of community engagement, climate science and the built environment. And I situated some of our work right in the intersection of those topics, which in and of themselves are very deep, and very complicated areas of research and scholarship as well as practice. And so this time I was walking around a lot in the industrial areas of close-in southeast and northeast Portland. And one of the things that comes up is a lot of these buildings were formerly big plants, they’re kind of meatpacking plants. They were probably warehouses, they had lots of different industrial and commercial practices, and we’ve taken some of those and kept those in there. But we’ve also made them into offices and we’ve made them into multi-family residential developments. And I happen to be observing the number that had just turned to multi-family residential yesterday. And I noticed that of 20 on one building of 26 units that were there, only four of them had window unit ACs on them. And these are solid brick buildings and these are concrete buildings. These are cinder block buildings and the sun when it hits those materials, just really is pulled in, holds on to that, given the density of those materials and then re-radiates it back out when temperatures get a little bit lower. And so the communities that are living inside many of these buildings, or in a sense, working inside these buildings without AC, are really feeling the brunt of that heat wave. And it’s not surprising the specific locations of the deaths that we saw in the past during the heat dome that came through in late June.

Miller: Do those buildings, those materials also radiate that heat outward, meaning if you’re on the street around those, is that also one more way to, to make the land around those buildings hotter later in the day?

Shandas: Correct. Yes, that’s really where this is very noticeable. We actually took some of these very sensitive thermometers, and we bring them close to the surface. And as soon as you get to the surface, it was coming in at about 125-130 F, right on the surface temperature. And then you lift the thermometer up a little bit higher and within one ft off the ground you’re already starting to see a precipitous decline, but still relatively high at about 108, 115, 114 [degrees], in that range. And then you go up to where our head, let’s say two meters or five ft to six ft above the ground is, and you start seeing that temperature is roughly around 104 or 105. So there is a column of air that kind of mixes up and moves that heat around. But generally speaking, that’s absolutely right. The hotter the materials get, the hotter the ambient environment or air temperatures get.

Miller: Now those numbers, they sound high, but they’re nothing compared to what you found in late June when you went to a particular intersection in Lents, this was Southeast Woodstock Boulevard and 92nd Avenue. Can you tell us what you found there?

Shandas: Yeah. So we’ve been conducting these, what we call heat campaigns, where we get these sensitive temperature measurements and we go around all over a region and we’re collecting these at one-second intervals. So every one second we’re able to pick up on what the air temperature is. And this area that you identified of Southeast 92nd and Woodstock has consistently shown up as one of the hottest places in the region. We found this also with Cully, we found this in neighborhoods that go mostly towards east Portland, and Hazelwood, in Centennial, and also in St John’s, and downtown areas as well. And so there’s this real clear indication about where the temperatures are hottest. And we were looking at temperatures at surface level of 180° during the heat dome, of surface temperatures right on Woodstock Avenue there at Southeast 92nd. And then air temperatures, we were also picking up at about 124 F air temperatures in some of these neighborhoods, whereas when we went to other parts of Portland, we were finding it didn’t it barely broke 100 degrees. It was still at the 99.5 Fahrenheit level, and we were able to really learn from that experience, that not only does that disparity increase when we are seeing higher temperatures, but as temperatures kind of tick up even higher, we see that disparity growing even larger. So, on average, on a 95-degree day, like we might have today or tomorrow, we would see a difference in neighborhood to neighborhood of about, let’s say 15 F is what we’ve been able to on average pick up. But that day, when it went up to 115 on the kind of monolithic number you get for a single place, we were able to see a 25 F difference from one neighborhood to another. So that’s an entirely new scientific finding, I think in the literature, as far as what we’re understanding for urban climate science and we’re writing it up now. But it’s still gonna be some time before we really wrap our minds around the complexity of how the urban landscape is mediating some of these temperatures.

Miller: What are some of the specific attributes of those neighborhoods? For example, that intersection in Lents, but some of the others you mentioned, that make them so much hotter than other parts of the city.

Shandas: Yeah, I would want to start responding to that by going back almost 100 years, as odd as it may seem. I want to go back to how we incorporated specific neighborhoods, where we put massive infrastructure like I-205 and what decisions were made, and who was at the decision-making table when those big freeways were going in when those big box stores were going in, when a lot of the infrastructure that we sometimes may take for granted as we move around our region, those things were all put there explicitly and with very conscious deliberate planning efforts in place. And what we end up seeing in these hottest neighborhoods are massive large infrastructure projects like freeways, like big box stores, like large parking lots, like buildings that will be multi-family residential. And I would just kind of point to the fact that when we have policies like what we saw coming out of the 1930s, with red lining and segregation that had happened, neighborhoods were disinvested over time. And when you have less investment going into a neighborhood, you see the materials that are being used for buildings, you see the kinds of big projects being put in into those areas because their land rents are lower. And by design, that’s an attractor for a lot of these large-scale industrial commercial projects that get established there. And those come with large parking lots, those comes with black asphalt parking lots, those come with ways in which the wind is blocked in which the sun’s radiation is really absorbed and not let go. And that dense materials that’s used in those places hold on to it and lack of tree canopy and green spaces in those areas as well. So we really see a multiplicity of factors that emerge now as a result of things that have happened even almost 100 years ago.

Miller: If you were elected to the Portland City Council and put in charge of a new bureau, the Bureau of Heat reduction, where would you start? Because what you’re talking about is the real history and its reverberations to this day. But here we are now. So one of the big questions is, where do we go from here? If you had that power, what would you want to do with it?


Shandas: Yeah, I kind of explore these a lot and I really try to get into the ear of folks who have a lot of power right now with some of our science, but also with some of the emerging understandings that we’re getting about how communities are responding to heat waves. And what I would do is just three parts. I’ve been thinking about this a lot, and really start with this idea of social infrastructure, the idea that these 96 people who the Oregon medical examiner has identified, who died directly attributable to the heat wave in Oregon, those folks were largely socially isolated and didn’t have family, friends, networks, very likely, to be able to lean on for fighting cooling resources. So what I really want to start with is the idea of an engagement and a communication system that allows us to be able to get out to multi-family residential developments, to residents that were in mobile home parks, RV parks, to transient folks, folks experiencing houselessness, and really building out an engagement plan with multiple bureaus coming together almost an inter-agency task force if you will, to be able to identify the multiple pathways by which people have died in this heat dome event. Because these are going to become more frequent and more intense, as we’ve been seeing happening through empirical assessments over the last decade. I would start there with the social side. I would really move into the infrastructure side of it. Next is looking at, call it this rainbow infrastructure plan, where it’s green, blue and gray. It’s not a full rainbow, but it’s the idea of thinking about the gray infrastructure, like our electrical grid, for example, which is decades old at this point and the likelihood of increasing air conditioning, which we’re already seeing grow in the region, not only in Portland, but Seattle and elsewhere in the Pacific Northwest, that’s going to tax the electrical grid pretty severely. And if we have rolling brownout or blackout that will spike the number of people who would likely face severe consequences as a result of increasing temperatures because they don’t have their AC that they were depending on any longer. I would look at green infrastructure as a way to think about what are the green walls, what are the street trees? What are the parks and green spaces that we can use this kind of nature-based solution to be able to cool spaces in effective ways, and find maintenance programs for that particular green infrastructure. And then finally, the blue infrastructure . . . we take stormwater, for example, just push it out as quickly as we can from a city. Let’s think about stormwater as a resource. Let’s think about using the waterways. Water is an amazing compound in our built environment that we’ve completely decimated and kind of eliminated as quickly as we can. So how can we think about blue infrastructure in our cities a bit more consciously, in relation to heat, as well as wintertime flooding?

Miller: Okay . . .

Shandas: And then finally . . .

Miller: You just tell us the last one. I have so many questions basically [about] everything you just said.

Shandas: Yeah, I’m sorry, I’m probably going on about this too much because I dream about ...

Miller: This is why we invited you because you’re dreaming about it. But so the last thing and then I want to dig into some of the things that you’ve been talking about.

Shandas: Sure, the last one is just a policy. There’s not a city in the country right now that’s actively putting codes, regulations and other kinds of standards for heat-sensitive development. What if we were to think about something like a heat overlay zone in the city? We have environmental overlay zones. What if we were to think about a climate overlay zone more generally, where any new development that goes into specific parts of the city would actually be held to a higher standard in terms of whether it’s amplifying temperatures in those areas because we know that certain kinds of development really do amplify temperatures. And not only do the communities inside those buildings suffer, but those adjacent also suffer. So that’s something I would really like to think about is, what are the ways we can think about policy levers to be able to move something like a heat-sensitive design and development code in the region?

Miller: So I do wanna remind folks by the way: I’m talking right now with the Vivek Shandas is professor of climate adaptation at Portland State University and we’re talking about ways to make neighborhoods more resilient during ever-worsening heat waves. So trees were one of things you mentioned, that was in the green category. You’ve already shown in studies and you’ve talked about it recently, that you can actually see more tree canopy in neighborhoods that were not redlined in Portland, than were redlined. When you go around with your sensitive thermometer gauges, how big a difference do trees make?

Shandas: It’s a tricky question in some ways. I can say ‘averages’, because on average we’re seeing upwards of 10 degrees F, that I can say just straight up, not only from the Portland region. We’ve looked at Tacoma, Seattle, King County, Eugene, Oregon. And so we have a good sense for the region, that’s about 10 degrees is what we’re seeing in an area that’s highly canopied versus one that lacks. That said, there’s a number of other factors that play out. For example, if there’s trees that are dispersed around a neighborhood versus clumped together. That’s a difference that we can observe, that the dispersed trees actually are offering shade in more areas, especially if they have large canopies and they’re able to prevent that direct solar radiation onto the black asphalt roads that are adjacent to it, that are such attractors for heat. We’re also seeing [that] if you put a few trees into a Southeast industrial area, for example, where I was just yesterday, those trees are incredibly ... they’re living creatures, if you will, and they also suffer stresses of heat. And we’ve observed through collaborations with folks like Aaron Ramirez at Reed College, who’s a tree physiologist, that the same tree in a hot part of the city that we were able to measure, really faces some severe stress compared to the same tree in a cooler part of the city. So the life, the kind of length of life of the tree, or the mortality that that tree may face, is going to be really compromised by the stresses that it has. And so thinking about how and where to distribute the trees and how to care for them. Really, that’s something that we’ve really got a bottleneck in the city around right now.

Miller: You mentioned the black asphalt, which in so many ways seems like the opposite of the green tree, in terms of its absorbing so much sunlight, then reflecting it back to us. What can be done about that? This is already, this is on the ground, this is everywhere. And in some neighborhoods, it’s certainly more than others, but it’s there now. So what do we do with that?

Shandas: Yeah, there’s like the severe option of changing the road structure itself. We’ve got this idea that we’re working on, where you’re actually thinking about other things that can happen on the road. We’ve done an enormous project in many cities around the country, including Portland, which was one of the first to do these bioswales. So we’re actually taking up a portion of the road for infiltrating stormwater during the rains. Those actually also benefit the temperatures in those areas, and reduce the amount of asphalt on the road, in some cases pretty substantially, because they’re right there taking a portion of the road. Now I hear a lot of cries about ‘I’ve lost my parking spot. How dare you take that spot for me with our green friends here’. But that aside, and the parking challenges that the cities of course are experiencing aside, the idea of reducing, kind of putting the road on a diet, if you will, and trying to think about reducing the overall asphalt, is one way deep paving really lends itself to those kinds of strategies. And we have a community-based organization called Deep A that we can lean on for these kinds of activities as well. So we’re ready to go with that. There’s also shading structures. We have lots of places that have been experimenting with big parking lots and thinking about parking lots that have shade as well, as you put some solar panels on that shade, if they’re mechanical shade structures. You put solar panels on those to be able to not only shade but also generate electricity from that. And I’ve seen a lot of those deployed in different parts of the country, it is really helpful. And another big thing people are trying is lightening the road coloring. So actually introducing material into the aggregate that is used for road materials, like we have seen in Tokyo and a few other places where the color, the absorbing ability of that road is reduced. It’s called, it’s a technical term of albedo: the reflectivity of that particular surface, and when you change it, and make it a little lighter gray if you will. It’s actually reflecting off a lot more of that. I’m not a big fan for painting roads white as a lot of folks in L.A. and other places have tried, because I think it brings a number of other challenges, like glare and other issues we still haven’t even studied yet. But I do think there are a few options for the existing roads out there. And we have so many road projects happening right now, out in Southeast Division and seeing lots of road projects. Can’t we be thinking about heat and stormwater and climate-induced stressors as we’re thinking about each road project? And one of my interests is really trying to get folks like transportation bureaus involved a bit more in the direct mitigation effort for heat and other climate-induced stressors,

Miller: Unlike tornadoes and earthquakes, we normally have many days to prepare for heat waves. They do not come out of nowhere. They develop as weather systems and then they hit us. You’ve been critical, especially of the government’s planning in response to the late June heat wave. It’s worth noting that many of us in the Portland area got ear-splitting emergency warnings on our cell phones just a few hours ago. I’m curious what your grade is for local or state governments in handling this current heat wave.

Shandas: Oh boy, I do a lot of grading at the university. So this is a tough one because I tend to put the grade up to how much learning was actually, that’s a big metric I use, for not just someone coming in with a lot of knowledge about it, and then just getting an A in the class, but this is really about learning, and I think this is …

Miller: You’re gonna give somebody a most improved award?

Shandas: Yes, correct. Right. And in this case, I think we are getting better at it. And definitely, I’m talking to city bureaus right now more so than I have in the past, even though I feel like in some cases I’ve been screaming into an echo chamber with these studies, and showing that these vulnerabilities are placed-based, that they’re actually perfect convergence of social vulnerability, combined with the built environment and a heat wave. But that said, I would say, the June event, I would say it’s probably passing but probably not much higher than a C-minus, a D-plus, is where I would go with that. We luckily didn’t have massive – like electricity – infrastructure failures, and that would have just spiraled this into a whole other realm of concern for me. But the fact that we open cooling centers so late, we communicated it so clumsily across the community. We didn’t account for the fact that libraries might not be good places for somebody to bring their pets, their sleeping bag or blanket and spend the night there. Most of the heat-related deaths actually do occur at night when you’re asleep, and your body is not thermoregulating and that’s where it really takes the biggest brunt of the force from a heat wave. And yet at the same time, that said, there [was] also the Oregon Convention Center, amazing place that has a lot of space. What if we were to think about resiliency hubs such as schools that are open, that are available potentially during a summertime heat wave and that have a lot of space? What would happen if we were to upgrade the cooling systems and the Merv filter systems, so that [there is] cleaner air moving through it, and having schools, neighborhood schools serve as a way to find some respite. So we could have done a lot more in the June heat wave. And I think this, this response more recently was a bit more calculated and a bit more thoughtful. Yet I think we still have a ton of work to do.

Miller: Vivek Shandas, thanks very much for giving us some of your time today. I appreciate it.

Shandas: Yeah, thanks for having me.

Miller: Take care of yourself. That’s Vivek Shandas, a professor of climate adaptation at Portland State University

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