 winter day. This is Howard Wigg, Think Tech, Hawaii, Code Green, and are we gonna be green today? We're gonna be as green as the beautiful trees outside and as cool as the beautiful trees outside. And if we have anything to do with it, we will be greener and cooler in the near future. Thanks to Dan Dennell, our esteemed guest for the day and is the president of Trees for Honolulu. But before I get to Dan, I have to mention his heritage a little bit. In the, it was the upper place to see, I believe, when I was a grad student at UH, just came back from world travels. And I was very concerned about the environment that I was casting about on the UH Manoa campus for fellow travelers who way, way, way back then were pioneers in environmentalism. And I met a, the head of the Urban and Regional Planning Department, he had founded it, and that was Tom Dennell. And he and I became good buddies. And he did a good job of being reproductive and he and I assume his wife spawned Dan Dennell, who is our esteemed guest today. Welcome, Dan, so much. Good chip, chip off the old block here. Well, Howard, I'm not sure I've ever had an introduction like that before, but it's wonderful to be here. And yes, I'm, I'll proudly take my heritage. Yes. Yeah, yeah. Yeah, Warren Buffett calls the, calls it the embryotic lottery when you're born into very fortunate circumstances. So all of us Honolulu residents, especially those of us who are blessed to live in cooler areas, we both turn out to be Manoa residents, we notice the temperature difference between where we are in Manoa. And when we get down to the flat lands, and it's not just greater access to the trade winds, it's not just the greenery, or it is the greenery. And when we get into the urban areas, we experience the urban heat island defect. And I have done measurements contrasting my home with the flat lands, the city area, and it's eight degrees. If it's 88 in the city, it's about 80 at my place. And all these winter mornings, when I leave, I leave very early, but I actually have to turn the heat on because the valley is so blessedly cool. So, Dan, take it away, tell us, is Honolulu as cool now as it was in 2030, 4050, 6070 years ago? Or have things changed? Well, no surprise to you or your viewers. Have changed. They're continuing to change. And it's really a serious situation because people don't realize it, but heat is the number one weather-related killer in the United States. So I don't know if you want to be number one in this category. I mean, it beats hurricanes, earthquakes, tsunami, any type of weather-related catastrophe, and it's heat. And you may even recall last summer, the Pacific Northwest, record heats in Seattle, Portland, British Columbia, and it's a silent, insidious killer. And Honolulu is suffering in the same way. And we have a couple maps here we can show if you want to bring up the first slide. This is a transect of the urban area of Honolulu. This is three to four in the afternoon. And volunteers went out. They measured the heat, and the red areas are hotter. The green areas, or blue in this case, are measured cooler. And then the green areas are the mountains and elsewhere. And if you go to the next slide, this is after the sun has set. This is 7 to 8 p.m. at night. And you can still see those red areas around downtown Honolulu, around Kakako, the edges of Pearl Harbor. And what's happening, Howard, is the buildings, the built environment, is retaining the heat. And what it doesn't have are those, you see the fingers in Manoa, Palolo, New Iwano, the valleys are blue. They're losing heat because they're surrounding areas and they have greater tree canopy. So, you know, it's a big problem, and it's gonna, it's worse today than it was in the past. And it really is a creeping disaster. And I'm so happy to be here and talk with you, who, you know, you're a great expert in, you know, solutions to heat. So, maybe we'll get into that a little bit. Yeah, somehow the phrase urban heat island defect comes to mind here. Yeah, absolutely. I mean, the heat islands are really what they sound like. They just, they retain the heat well past the evening hours. And it's a big problem because the earth needs to cool. And the next morning, in order to have a cooler morning, it needs to cool down overnight. And this is not a problem you need to Hawaii. You see this around the world. The issue, though, is it's getting worse. And what's going to be happening are the health outcomes. You know, people who are older and youth, particularly babies, infants, toddlers, they have a hard time regulating heat. And it's going to be ordered already as I really should say, a problem. And it's a problem where there's different approaches. And love to talk more with you about the green approach, since that's code green today. Precisely. Just maybe to simplify an example of urban heat island defect. If you are barefoot on asphalt, black asphalt in the middle of a sunny day, the asphalt is so hot, you cannot, your feet cannot stand it. But if you were to remain on that asphalt and a cloud, great big cloud came over and obliterated the sun for a long time, you could stand there for a long time and that asphalt would still be hot. It wouldn't just immediately give you a relief because there's the concept of absorptivity. The radiant heat absorbs into that black, rough asphalt and it stays there and it emits back to the atmosphere just very, very slowly. This is something I'm personally involved in. I sit on the board of the Cool Roof Rating Council and we just formed the Cool Wall Rating Council. And the idea there is to get into building codes, reflective roofs and reflective walls. And then we have a subset of the urban heat island defect. Just a little aside there. No, I appreciate it. You're an expert on green roofs, on building codes and these are all, I guess that may be my main message today. There's not one single solution. There needs to be multiple approaches. It's not one size fits all, but we need everything here. We need the building codes to change. We need green roofs. And in particular, my organization, Trees for Honolulu's Future, we believe we need more trees because trees bring tremendous benefits, not just for the heat island to mitigate the heat island effect, but look at the trees. They sequester carbon. They make oxygen. They provide the shade that you were just talking about. They capture stormwater runoff. They work so hard for us. And for viewers, just think right here in Honolulu, compare Kupiolani Boulevard, the street between downtown Honolulu and Alamoana Center where you've got the monkey pod canopy over the street. And compare that to South King Street, same areas, downtown to University Avenue. And there are very few trees. Where do you want to be? Which has higher real estate values? Where is commerce and life more vibrant? And I would premise that it's Kupiolani Boulevard, not South King Street. I'm glad you mentioned the value of real estate. I had the good fortune many years ago to be staying with a friend in El Paso, Texas. And it was winter. And she had a view, a valley view of a lot of El Paso and a view of Juarez, Mexico across the Rio Grande. And El Paso, you just green, green, green, these red tile roofs and then more green, more green, more trees, more trees. And then El Paso was just this shroud of blacks and browns. It was really inhospitable looking in contrast to El Paso with all the trees. And we as a nation are a heck of a lot richer than Mexico. And it was just reflected, among other things, pun intended, reflected in the amount of trees there. Well, well, you talked about the amount of trees and really the wealth and the privilege that we have. I'm here to say we've got some bad news. If you want to bring up the next slide, Honolulu, we're actually losing urban forest. And this map here, the dark maroon color, 5% to 7% loss in two periods of time. This was 2010. And then again in 2013, using Lidar data, you can see the Kalihi Pearl Harbor area. And unfortunately, the Kaimuki Manoa Pololo area as well, losing the most trees, but every single part of the island, the urban part of the island lost tree canopy. And that's a big problem. And pretty excited because our organization, we're working with the city and we'll get some updated data and we can really see how we made a difference in the last few years. But how do we stack up to other U.S. cities? If we go to the next slide, we'll see Honolulu is on the bottom third in terms of urban tree canopy. And this is kind of sad. I mean, we are a tropical environment year around growing season. And our canopy is about 22, 23%. And the city's stated policy is to get the 35%. And just to give you a sense of the context there, 35% is where Washington, D.C. is today. And so Washington, D.C. might not be pleasant politically, but it's pleasant in terms of the environment and things around the city. And Honolulu, we need to get there. And people often ask me, well, why, Dan? Why have we cut down a large swaths of urban tree canopy? And the fact is, it's not that. It's you lose a tree here, you lose a tree there. It's the cumulative effect that has caused us to be in this situation where we aren't today. Yeah. Even in the back of Manoa where I live, the house in back of me was very tree enshrouded and a new person moved in. And she decided to chop down some beautiful, over large canopy trees. And lo and behold, shortly after that, an AC system appeared. AC in the back of Manoa Valley, you can only, you only need that when you have exposed yourself to all the sun's radiant heat directly. You know, what a sad story to share, but it's a real story because people are just taking their unilateral action and without really any regard to the community impact. And and then the fact is, you remove these canopy shade trees and install AC, which then further compounds all the energy issues. And yeah, it's a real sad commentary. If you want to call up another slide here, we'll stick to the Manoa area. You're familiar with this, is the University Avenue off ramp, looking in the cocoa head direction from University Avenue. And the upper shot was July of 2019. See a couple of trees there. You know, things are good. It's the height of summer, but the grass is green in 2019, by the way, was one of the hottest summers on record in Honolulu. And then the DOT removed the trees. And you have the shot below the May 2020. And you can see that there's bare dirt. The grass is now dead. And, you know, the reason the trees were removed was because homeless were living under those trees there. Now, that's unfortunate. But the removal of the trees didn't solve the homeless problem. It just moved that problem somewhere else in the Moeli area. And this is the kind of example that we're having time and time again throughout Honolulu. And our organization, we advocate for trees and the public policy around trees. So, you know, State DOT removes those three large trees. They were there for decades. We don't want them to just replace three, you know, trees, skinny trees, tree for tree. We want them to replace a lot more trees because if we don't do that, we'll never catch up. We'll never turn this ship around where you're seeing removal of trees and increasing heat, increasing the heat island effect. And, yeah, whether it's in neighborhoods where you live, where you work, where you transit, trees have this incredible, incredible value. And just removing them without a plan, without a replacement, without any thought is just a really unfortunate thing. And somehow the word transpiration comes to mind as does the phrase nature's air conditioners. Can you go into that a little bit? Yeah, absolutely. You can probably talk to the science much better than me, Howard. But yeah, the trees actually create really almost a misting system. So you can, you know, you go to perhaps the water park or Disneyland or something and there's misters there. Well, trees do that as part of natural air conditioning. And it creates a wonderful cooling effect that is, you know, something that is truly remarkable. And I think Al Gore wrote an op-ed piece in the New York Times a couple of years back. And he's like, you know, the best invention for climate change, for sequestering carbon, for cooling is something called the tree. You know, nature has invented this incredible air conditioning system. So the proper placement of trees, you know, vis-a-vis your buildings and so forth will make a demonstrable impact, a very positive impact. So yes, you are among the enlightened ones, I'll say. And in terms of transpiration, you have the water in the ground getting into the roots, traveling up the trunk, spreading to the branches, getting into the leaves, and then the leaves, the moisture in the leaves evaporates. And when you have evaporating water, you have a temperature reduction. As I said, I'll just, you know, we may have to rename you Dr. Science because you've got the science down pat. And that's the amazing thing. I was thinking about it before the show today. You don't even need the empirical measurements. You can just go out there and experience it yourself. You know, where would you rather be if you're watching your child or grandchild soccer game? Watch where the parents and the grandparents sit. They're under the trees. They're not out of the sidelines in the sweltering heat. And people are, if you will, voting with their behavior, with their feet. And that gives us a lot of hope. But we, you know, our organization, we want to educate folks more about the value of trees that, you know, it really shouldn't be a question of why plant a tree. It should be why not plant a tree? Yeah, just empirically, I had some time on a hot summer day. It was actually, I think on Moloka and I had a heat gun because I was going around buildings measuring heat coming through the windows and so forth. And I, this is the middle of the day, very sunny, pretty hot. I measured the asphalt temperature in the direct radiant sun, 142 degrees, the asphalt, not very pleasant. Then I walked over to the same asphalt shaded by a tree, so 102 degrees. Then I went right next door, shaded tree, grass, 89 degrees. Just incredible information stored right in that little informal experiment. Well, you'd be excited to learn. We recently got a Environmental Protection Agency grant award to work with young people in the Makalapa area of Oahu. And we are literally going to be working with elementary, middle, and high school students to do exactly that. Measuring the heat in the parking lots, in their buildings, in the grassy fields, and then working with the students bringing in outside experts and others to talk about various ways to mitigate the heat and let the children, student scientists, come up with solutions, solutions that work for their school, for their home. And we're real excited about that and really brings to the fore should, you know, the EPA or other regulators regulate heat. You know, that is a question. You know, we regulate other pollutants, but we don't really have regulations around heat that perhaps we need in order to not just further the conversation, but to further the action necessary. And just in terms of policy, when a new neighborhood opens up, I'm thinking single family residents or townhouses, is there a requirement that X number of trees spaced X feet apart be part of that new development? Yes, there is. And the city ordinances require it, they require a certain number of trees and parking lots and so forth. But we do have a problem because what tends to happen is the trees are the last things addressed. So they've laid the sewer pipes, they've got electrical conduits and, you know, water lines and so forth. And at the very end of the discussion becomes the trees. And you just can't plop a tree anywhere. They need space and they need space underground and they need uncompacted soil. So, you know, part of where we're working in, in fact, I'll be one of our certified arborists now are speaking with engineers tomorrow in a conference talking to them about the value of putting the trees up front in the conversation. Don't wait till the end when you have everything else laid out and then you're kind of scratching your head going, where do we put these required trees? It's really an unfortunate way to be looking at it. And then moreover, the current ordinances are really they talk about a tree in the caliper, the diameter of the tree. And they're not terribly worried about the canopy. And we're worried about the canopy. We want to see the large shade trees, the type that your neighbor sadly removed, because we believe that's going to make the biggest impact. So, you know, we call them the lollipop trees, you know, these trees that are just small, have a nice little crown, and that's it. Those trees are, they're okay, but they're not going to create the kind of city that we need in the future. Yeah, somehow the monkey pod comes to mind there. That's one of the greatest canopy spreaders around. Yeah, yeah, absolutely. And earlier mentioning the Peelani Boulevard and, you know, those monkey pods and other trees provide just a lot of value. And that value is in that canopy. And yeah, so that a lot more policy work to be done, that's for sure. Have there been any studies done about neighborhood to neighborhood tree canopy percentage one neighborhood to the next and then the value, the home value in that in those neighborhoods? Yeah, we actually have access to data that can look neighborhood by neighborhood. We haven't cross tab that with the values of homes in that neighborhood. But you would think that there would be a correlation of the kind of key area where we have a project is under tree in comparison to some of the surrounding parts of urban Honolulu. And part of our theory there is the change that's occurred, you know, talk with old timers and they'll say, oh, yeah, you stamp the mango and the lychee tree in the backyard, those got removed, the monster homes have come in, people are building, you know, to the full zoning lot. And these things add up. So absolutely, we can compare it. We just haven't done that. There are comparisons done to other indicators, income levels to health outcomes and so forth. And no surprise, you'll get better health outcomes with better canopy, you have higher personal wealth in areas with more trees on New York Times. And it's actually on our website linked to an article that actually looked at this very extensively. Beautiful. On that very, very, very cheery note, then we must bid fond farewell. But I know that you are bringing this group of kids up and look forward in six months, 12 months, whatever, to having you back. And I want some kids participating in the program too. Give them that experience. I promise you the kids are much, much cuter than you and I. And I would, my thought is they'll probably be much smarter than you and I. So they are the future. I mean, I don't want to sound trite, but the work being done now is not only for today. It is really for tomorrow. That's what makes it so critical. Absolutely. I would do a couple of quotes, but we are out of time. Thank you so much, Dan Dennell. And I promise we will be back for a cooler future. Thank you, Howard. And just remember, winter loads is hot, but trees are cool. Okay. Fond farewell to all, Howard Wigg, Code Green. Think, tech, kawaii. See you next time.