Designing for climate change

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{***Noah***}

Coming up on Harvard Chan: This Week in Health…

Designing buildings and cities for climate change

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(We are really testing the limits of the performance of these buildings that traditionally were constructed to deal with predominantly cold weather. We have an aging infrastructure. This is something that we have to address for the billions of people that live now in cities, and that will live in the future.)

New research shows how extreme heat can affect cognitive performance of young adults. And in this week’s episode, researchers say that the new findings highlight the need to design buildings and cities that can adapt to our changing climate.

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{***Noah***}

Hello and welcome to Harvard Chan: This Week in Health. I’m Noah Leavitt.

Extreme heat can have severe consequences for public health and is the leading cause of death of all meteorological phenomena in the U.S.

And climate change means our world is getting warmer: 2016 marked the warmest year on record for the past two centuries.

But the issue isn’t limited to warmer temperatures overall—climate change will lead to more extreme weather events—such as intense heat waves. And in this week’s episode we’re talking about how our buildings and cities should be re-designed to deal with this threat.

We’ll be talking with Harvard Chan School researchers Joe Allen and Jose Guillermo Cedeno Laurent—he goes by the nickname Memo, which you’ll hear during the episode. They recently led a study examining how extreme can affect the cognitive performance of young adults.

They found that students who lived in dormitories without air conditioning during a heat wave performed worse on a series of cognitive tests compared with students who lived in air-conditioned dorms.

The findings are important, because they show that the effects of extreme heat are not just felt by those typically thought of as vulnerable—such as the elderly.

They also underscore the need for sustainable design solutions in mitigating the health impacts of extreme heat. And that’s what Allen and Laurent are aiming to do through their work with the Healthy Buildings Program at the Harvard Center for Climate, Health, and the Global Environment.

I began my conversation with Laurent and Allen by asking them what inspired them to look at the effects of extreme heat on cognitive performance.

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MEMO CEDENO LAURENT: Usually, we see that the newspapers– the media– grab the very extreme outcomes of a heat wave, like mortality. And rightfully so. It’s very important. But sadly enough, we don’t do anything to change the real cause, that we think it’s climate change.

So in order to address that, we wanted to understand, what would be the effects of a heat wave in a population that we normally considered immune to these effects? And young, healthy individuals living in buildings was the perfect opportunity. Buildings with and without air conditioning.

NOAH LEAVITT: And so the idea that, as– and we think we’re already seeing this, but– and in fact, the climate changes that we’re likely to see more extreme weather events. So it could be heat waves, but it could be snowstorms. So this is a way of showing the potential effects of climate change going forward. Is that one of the goals?

JOE ALLEN: Yeah, that’s right. If you look at just this past week in Boston, we all experienced that major heat wave. And like Memo just said correctly, I think a lot of times we think about these extreme effects. And they are important and real, but this is what shows up in the newspaper.

And what most of us probably don’t realize is that there’s these subclinical effects happening. And this study looked at the impact on cognitive performance. So instead of thinking about maybe the dozens or hundreds of people affected, it’s actually millions of people. It’s all of us.

NOAH LEAVITT: And so you talked about looking at cognitive function. So can you describe a little bit about your method with this study, and how are you actually measuring the effect of these heat waves on cognitive function?

MEMO CEDENO LAURENT: So the study methods that we use are pretty simple. These cognitive tests that we use have been validated widely. And they are, for the first time– as long as we know– used in a field study during a heat wave.

So one is a color-word test, or known as a Stroop test. And this one ask the participants to identify the color of a word shown in the screen as fast as possible. And this becomes especially difficult when the color of the word and the word shown is mismatched.

And we used another validated tool that is an arithmetic test. Adds and subtraction. And we measure how fast people respond to these answers. But also, how accurate. So how many correct answers per minute participants are able to answer these things. So it’s reaction time and a way of measuring the accuracy.

NOAH LEAVITT: And so then what did you find in terms of the result of these cognitive tests in terms with the students who were in the air-conditioned dormitories versus those who were not in the air-conditioned dormitories?

MEMO CEDENO LAURENT: So the results were that the students that don’t have access to air conditioning were slower than those with air conditioning in both tests. And also, they were less accurate. They were able to respond less correct answers per minute in both tests. So it was pretty consistent. And it’s also something that has been reported previously in experimental studies. So in many ways, this is just confirming what other studies have done.

But this time, what we think is special about this study is that we were able to do it following a heatwave. So we’re able to follow the different temporal and spatial patterns of the exposure to heat. That is something, I would say, noteworthy about our study.

NOAH LEAVITT: And so I wanted to ask about that. Did you see at all, for example, that as the heat increased, that the responses may have been slower? So was there a link between the actual temperature outside and then the results of the test?

MEMO CEDENO LAURENT: More than the temperature outside, it’s the temperature in the spaces, in their bedroom. So this is also a departure from most of the body of literature that is based on epidemiological studies that use outdoor temperature as their marker of exposure.

So in this study, we were able to characterize the indoor environments very thoroughly. So we measure temperature, relative humidity, carbon dioxide– which we know thanks to research from our group, it’s also one of the exposures that determine cognitive function– and noise. So by doing this, we have not only the measurement of temperature, but other environmental parameters that could affect cognition.

JOE ALLEN: If you think about what Memo said there, what’s really interesting in the study, I think, is that the study design had four or five days before a heat wave. Then we track people during a heat wave, and then follow them after the outdoor heat wave was declared over.

And if you think about this in terms of temperatures, leading up to the heat wave, it was seasonable. Maybe 70 degrees Fahrenheit. Indoor temperature’s similar for both air-conditioned and non air-conditioned dorms.

Then when the heat wave hits, temperatures go up to 85, up to 95 degrees Fahrenheit. The air-conditioned dorms stay comfortable, like you’d expect. That’s obvious. But the indoor temperatures for the non air-conditioned spaces get up to 85 degrees also.

The most interesting part, I think, is that after the heat wave ends, in terms of outdoor heat wave, temperatures drop. Air-conditioned dorms, temperatures stay cool. The indoor temperatures for the non air-conditioned spaces stay hot.

That’s what we call an indoor heat wave. The temperatures stay up. So even after this all-clear is declared, you don’t see it on the news anymore, you don’t see a heat wave heat alert anymore, or heat advisory, indoor temperatures can still be really sustained at a high level.

NOAH LEAVITT: And it’s interesting you went to that, because I feel like I even noticed that at my own house. It was really cool– it was cool and comfortable yesterday, but I noticed that, in my bedroom, I had the window closed. And it was really steamy in there. So I think it’s one of those things that people maybe notice happen, but to actually have the data to draw that link, I think is really interesting.

MEMO CEDENO LAURENT: Sadly, also, climate change, it seems to be happening right now. So these unprecedented levels of temperature allow for these natural interventions that are truly occasions that have never been presented before. So we are really testing the limits of the performance of these buildings that traditionally were constructed to deal with a predominantly cold temp weather. So this is new for all of us.

And talking about what Joe said before, this is something that will be the experience of millions of peoples across the world. We have an aging infrastructure. This is something that we have to address for the billions of people that live now in cities, and that will live in the future.

JOE ALLEN: Well, your experience is exactly right. A lot of times, we think we’re in the field of common sense. We’re doing studies. We’re quantifying what we all know and experience.

But the physics behind it is that, in a lot of these older buildings– like Memo said– is that they have a high thermal mass, or a potential to hold and absorb and store all that heat that they gain during the day. Well, during a heat wave, when it doesn’t cool at night, there’s no chance to re-radiate that heat. So the energy in the system just builds up, builds up, builds up. And when it cools off outside, and to your experience, you still walk into that building and it still feels warm, well, that’s all that embodied energy that’s been stored up in the materials in any of these northern climate buildings that are built with things like brick and concrete that have a high thermal mass.

MEMO CEDENO LAURENT: I would make emphasis on the night period that Joe just mentioned. Because during the day, we have the opportunity to look for shelter in malls, in other places that have air conditioning. But at night, we’re really limited in those options.

So most of the times, that is what has been seen to be the predictor for thermal deregulation. We de-compensate. As the heat wave goes on and on, we start to be sleep-deprived, and this becomes like a cumulative exposure, so to say.

NOAH LEAVITT: And so you talk about sleep deprivation. Is that one of the potential mechanisms of why this extreme heat affects cognitive functioning? And are there other mechanisms at play?

MEMO CEDENO LAURENT: There are definitely plenty of mechanisms, potential mechanisms. We try to evaluate sleep. We did it through some mediation analysis, which is– we acknowledge– limited because of the size of the study. And nevertheless, we found a small but significant effect of sleep. Meaning that temperature affects sleep, and therefore, sleep affects the cognitive effects that we saw on the students.

NOAH LEAVITT: And so you talked about the sample size. I think it was 44. So is one of the goals in the future [INAUDIBLE] if you could do a– maybe find another natural experiment with a larger group of students?

MEMO CEDENO LAURENT: Definitely. Not only students, but other populations and other set of health endpoints. So right now, we are looking at cognition. But we have to be cognizant that, in order for us to have a better control of temperatures in indoor environments, we also have to consider other activities that we perform indoors.

And we repeat over and over that we spend 90% of our time indoors. And we basically perform all the activities possible in these spaces. We learn, we work, we even love and sleep in these environments.

So there will be different ways of catering to these physiological needs. And that speaks about temperature, but also about other work that I hope Joe talks more about on how we’re looking at this opportunity of changing our built environment towards a more sustainable built environment promoting health.

NOAH LEAVITT: And we are going to talk about that. 90% is going to come up later in the interview. I promise you, I do have some questions about that. But just a couple more questions about this particular study.

Can you explain for people the significance of the fact that these were findings in young adults, in people who we would typically think of as young and healthy, and maybe you wouldn’t think of that there is much affected by the heat. So what’s the significance of the findings in young adults and college students?

MEMO CEDENO LAURENT: So I think the findings are provocative. And we think that this could have a lot of larger implications. It’s a message for the general population that these people that we considered very resilient to heat exposures, we are measuring the effects in them. So the question is whether we can identify these effects in other sectors of the population. And these might be even bigger effects.

So for example, the research of another colleague of ours here at Harvard, Jason Park, found the cumulative effects of heat in learning. So they use a massive data set of performance in PSAT tests, P-S-A-Ts, and they found that for every degree Fahrenheit higher of outdoor temperature throughout the academic year, there is a 1% decrease in the learning of students that don’t have air conditioning.

NOAH LEAVITT: I feel like students are going to hear this and say, see, you should add ACs to the schools, and add ACs to the dorms. So what is the takeaway? You touched on this idea of, broadly, we need to rethink how we’re constructing buildings for climate change. But in the short term, is this the kind of thing where you think that schools should consider maybe adding air conditioning, adding air conditioning to the dorms? What’s the takeaway there?

JOE ALLEN: This work is under the broader lens of the Climate Change Solutions Fund, so it’s all about solutions. And the solution can’t just be more air conditioning. So it’s a multi-pronged solutions that are needed.

This is everything from decarbonizing our grid, more energy-efficient air conditioning. It’s the smart use in ventilation and heating in so-called smart buildings, so we’re ventilating and cooling and heating where and when it’s needed. It’s next-gen refrigerants. And it’s even things that Harvard is pursuing on the Allston campus, like district cooling. So it has to take into account all of these tools that are at our disposal to address this problem, not just pump in more air conditioning.

MEMO CEDENO LAURENT: And I would just say that we would never think of, if we have a chronic headache, to just keep managing it with painkillers. We have to go to the doctor. We’re putting, really, the finger on the wound of what is the most pressing issue, and that is climate change. So we need to address that before we start just fixing these small items.

NOAH LEAVITT: And to carry that analogy a little bit further, it seems like what you’re finding is this is just one symptom of climate change in general.

MEMO CEDENO LAURENT: Right. Right.

NOAH LEAVITT: So I did want to talk about– you talked about [? you all start ?] with this idea of– Joe, you talk about this a lot– we spend 90% of our time indoors. You kind of have this concept called buildingnomics. Did I say that correctly? So I want you to talk a little bit more with that more broadly. How is the work you’re doing working to optimize building for health [INAUDIBLE]?

JOE ALLEN: Yeah, so this study fits into a larger body of work we’re working on as the entire Healthy Buildings team, a really talented group, I think, of postdocs, doctoral students, undergraduate researchers. And our framework is this buildingnomics idea. And we released two years ago this report called The Nine Foundations of a Healthy Building. And that is simply a summary of the 40 years of scientific evidence to date on how the indoor environment impacts our health. So that’s our health, our ability to think clearly, our ability to be productive.

One of those nine foundations is thermal health, and that’s what we’re talking about today. But it’s just one of the nine factors we’re looking at. So you can look at all of the work we have going on campus, in schools, in offices around the world, trying to distill, what’s the optimal combination of these factors to promote health? So we’re not always chasing or responding to so-called sick buildings. It’s how do you optimize a building in the first place?

And I’ll tell you what we’re doing on our own campus just this year around the nine foundations of a healthy building. So we’re starting to work with Harvard Business School to say not just, here’s what the science says, but how do you implement this? How do you put the nine foundations into practice?

And with one of our doctoral students, we’re doing that. So we’re working with the Harvard Business School. We’ve identified a couple buildings over there. And we’re talking with them, and monitoring, and optimizing their environment around all of these nine foundations.

So it’s not just research for research’s sake. It’s not ivory tower. It’s really, let’s put this into practice and really help people in their spaces that they’re working and living.

NOAH LEAVITT: And so for these nine foundations– there’s actually a great graph. Look at this, we’ll put in the website. But for people who aren’t familiar, in addition to thermal health, what are those foundations of a healthy building?

JOE ALLEN: Sure. So you can go to our website and look at the graphic. It’s at ninefoundations.forhealth.org.

But we think about air quality, ventilation, and thermal health. Then I think of the water-related ones. That’s water quality– drinking water quality– and moisture in a building, which is critical.

Controlling dust and pests. Working on lighting and views. Acoustics and noise. And then last is safety and security.

And so what we’ve done in this report is in, really, in executive summary style– two pages for each– we say, what is thermal health? What does the science say about how this impacts our health? And of course, it’s all fully cited back to the primary literature.

So that where we’re working from is really grounded in the hard science that says, this is what the science says. And in our opinion, there’s plenty of science. Enough to act on.

And then that’s what we’re doing right now at the business school, and even with some companies, saying we have the science. Let’s act on it. And then we’ll verify and show that then actually lead to improved performance of the indoor environment.

NOAH LEAVITT: And so I wanted to ask about companies, because we actually just did a podcast on this culture of health initiative, which is focusing on businesses and health. So are you finding that businesses or construction companies– engineers– are they receptive to this work and they’re saying, OK, yeah, we need to rethink how we’re organizing projects in order to build healthier buildings. Like you said, not just [? fix-it ?] buildings, but build healthier buildings going forward. So is the industry or companies responsive to this kind of work?

JOE ALLEN: There’s no question that this transition is happening. If you see the so-called green building movement over the past 20 years, a lot of focus on energy waste and water is now transitioning to a conversation around health. And we’re helping to steer that conversation.

We see companies and CEOs of these companies come to us and recognize that the building can be part of their strategy to promote health. And importantly for them, we have shown through our other research, the economics work out for them. So when you make these decisions around a healthy building, it’s better for the occupants in terms of their health, but it actually benefits the bottom line of the company.

And we see this uptake of the science in many different sectors. Big pharma, many of the big banks, commercial real estate around the world. So there’s an obvious move towards this big opportunity when we focus on people’s health. And it fits right in line with what’s happening here in terms of the [? cultural ?] health project, and that big MOOC that just happened.

NOAH LEAVITT: I know Gina McCarthy always asked about climate change and making it personal, and it seems like this work is really aligned with that. So how should we be thinking about the built environment, whether cities, buildings, et cetera, in the context of climate change? So both in the specific [INAUDIBLE], maybe on a larger scale. How should we be thinking about this kind of work in the context of climate change going forward?

MEMO CEDENO LAURENT: So I think there’s a clear signal across the world that cities is where the war on climate change is being fought. And we think of buildings as the actual battleground. So this is a scattered battleground, but it’s how strategically we could tackle the problem.

So at the unit basis, something that is intimate to us, the places that determine our health, to an extent, probably more so than our physician. Joe always talks about this. We go to the doctor and do a checkup every six months, every year. But we go every single day to the places that either makes us sick or makes us thrive.

NOAH LEAVITT: I’m sure people listening to this are probably wondering, OK, are there things that I should be doing in my own home to make it healthier? There’s the buildings– on some level, you’re at the mercy of your office building as an employee. But the things people [? should be doing ?] on homes that can have a measurable impact?

JOE ALLEN: It’s a great question, and we get this one a lot. And I’ll give you a hint to where we’re going next. So the Healthy Buildings program is at forhealth.org. We think that’s the big frame. Building for Health. Cities for Health is our new project.

And what we have coming soon is going to be Homes for Health. Because we keep getting this question. We know the similar science is there, but it’s sitting on the sideline. It hasn’t been put out in something that’s tangible and actionable.

So our team is working on that right now. And early in 2019, we plan to release what we call Homes for Health, which would be exactly this. Simple science behind why your home influences your health, your ability to sleep, your ability to think. And then practical steps you can take room by room.

MEMO CEDENO LAURENT: How you clean it, how you manage it. Should you really cook without opening your windows or turning on the fan on your hood, your kitchen hood? So simple things that really could make a difference.

NOAH LEAVITT: As you all have [? done this ?] work and built out this body of research, I’m interested, when you walk into a building now, what is your reaction? You instantly looking up like, oh, nice natural light. Good ventilation. Does this change how you just look at buildings now?

JOE ALLEN: For me, definitely. That’s who I’ve been. It’s who I am. I do it. I just naturally look around. I’m in this place.

But I tell you what we’ve been doing with class here at Harvard is we have this class that Memo and I co-teach on healthy buildings, and half of the class is fundamental lectures. But each class, we try to get out into real buildings. We take the students out, and you can see the progression over the course of the semester that, at the end of the semester, when they walk into a room, they’re doing the same things.

Where’s the air coming from? What’s the lighting like in here? What are the views like? What are the odors you detect? Do you smell musty?

So you can see this. Once you start learning about it, it’s hard to ignore the science when you walk into your kid’s school, or you walk into your own home and you look around with some fresh eyes and realize that maybe there are some things you’re doing that don’t quite match what the science says we should be doing.

MEMO CEDENO LAURENT: And the exact quote from one of our students is, “I will never look at buildings the same way after taking the class.” So it really happens. Yeah.

NOAH LEAVITT: So just a last question again, to quote Gina McCarthy. I know she often talks about getting involved locally. And that’s one of the best ways to make an impact. And I just wanted to ask you, because you talked about schools, for example. So for people who are concerned about their child’s schools or even their workplace, do you have any advice for getting involved, ways to effect change, ways that people can make an impact based on the science that you all are producing?

JOE ALLEN: Well, I’d say certainly for schools, I can address that. Because you won’t be surprised, we have a report called Schools for Health that details all the ways that the school building influences student health, student thinking, and student performance. And we’ve heard back from people that it’s been a really helpful resource, because when they want to approach their school or their district and say, what does the evidence say, or what should we be doing, it’s helpful to have this report from Harvard that’s based on all the peer-reviewed science that says why this stuff matters. And then so you’re able to affect change on a local level once you’re armed with all of that hard data on why it matters.

MEMO CEDENO LAURENT: Well, I would say that we are very vocal. We are spreading this message in every single forum that we get invited. And even in those forums that we don’t get invited, we’ll look for an invitation to speak. Yeah.

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{***Noah***}

That was my conversation with Joe Allen and Memo Laurent.

As they mentioned, you can learn much more about their work by visiting forhealth.org. We’ll also have a link on our website, hsph.me/thisweekinhealth.

Thanks for listening. A reminder that if you enjoy our podcast, please rate, review, and subscribe wherever you listen. It helps others find the show.