I have a BS from the Colorado School of Mines in Geological Engineering. And I also have a Masters in Physical Oceanography. I came to CU Denver in the fall of 2015, to pursue an MBA in managing for sustainability. And now I am working at the National Renewable Energy Laboratory, working as a renewable energy policy and market analyst. >> How great, that's a great combination of science and business. >> Yes. >> What I wanted to visit with you, is a project you did while you were finishing your MBA here on the greenhouse gas inventory, or the carbon footprint for the Denver Zoo. In our classes, we have cases and they're pretty contained. But in real life, there are some challenges to doing a carbon footprint. And I wanted you to talk about, maybe some of the data challenges, maybe the calculator that you used to do the final calculation. And then maybe we'll talk about a couple of specifics of the zoo situation. >> Yeah, so I was tasked to calculate the greenhouse gas emissions from Denver Zoo for the year of 2015. And I didn't have an industry standard, because there's about one or two zoos in the US who have calculated their greenhouse gas emissions. And most of those, have only calculated Scope 1 and Scope 2. So I was searching for a method of how to go about this, and I was able to problem-solve my way through it. Some of the data was pretty straightforward, we got water usage from Denver Water, and electricity from Xcel. So those were fairly easy to calculate. However, some of the difficult contributors were transportation from visitors. I got the data from the guest relations. They track about every one in ten visitors, what their zip code is. So based off of their zip code, I could calculate about how far they had traveled round trip to and from the zoo, and was able to extrapolate that data out. And in the end, visitor transportation was about 70% of the zoo's total greenhouse gas emissions. But that goes into Scope 3, most of the other zoos and industries, who've been reporting for quite some time, are just focusing on Scope 1 and Scope 2, because Scope 3 is so arbitrary. Another contributor to the greenhouse gas emissions was the animals methane production. And what I found out was there are ruminant and nonruminant animals. The ruminant animal has four chambers in their stomachs, so they're like a cow. They produce more methane because of this. And there is quite a bit of data on cow methane production. Because we can set up controlled experiments. But there's not a lot of data on wildlife and their methane production. So what I used was, I split them up into these two groups, non-ruminant and ruminant animals. And found out that an animal that eats mainly an herbivore diet, produces more methane. The carnivores produce an insignificant amount of methane. So based off those factors, and then if you add the animal's weight, I was able to calculate the amount of methane each animal produces in the zoo. [LAUGH] >> Half breaking. >> [LAUGH] >> [LAUGH] How about I put up the slide? >> [LAUGH] >> Is great, and it'll be a surprise to everybody, but the results are that giraffes compared to elephants, giraffes produce more methane. >> Yes, they do! >> And elephants are so big. [LAUGH] >> [LAUGH] >> Yeah, the difference is, a giraffe is a ruminant animal, so it just goes to show that they produce about twice the amount of methane that an elephant does. >> Who would ever thought to do a carbon footprint, chasing giraffes around? >> [LAUGH] >> [LAUGH] In terms of visitor commuting, it is an unusual thing to include in carbon footprint, yet we know it has an impact. And so, was there any discussion about who's really responsible for those emissions? >> Right, that was a discussion, who's responsible for those emissions? However, if you're going to the zoo, it's generally an all-day event. So I attributed those carbon credits to the zoo. And another challenge there was figuring out the out-of-state visitors. Do we attribute their air miles, do we attribute that to the zoo. Well, you would assume that most people aren't just coming to Colorado to go to the zoo, so we did not use those air miles. We did however calculate the distance from DIA to the zoo, and use that as our metric. >> A couple things were missing here, you had issues with, I think it was restaurant food a few other things. And going back and thinking about it, do you have any ideas on how you might deal with that now? >> I was working on, as the project was finishing up, unfortunately I didn't have enough time. I was working on the animal nutrition component of the methane production, figuring out the amount of produce and meat that come into the zoo and get fed to the animals. And the issue with that is, do you attribute the water usage, and electricity, and fuel to transport all that food to the zoo? Where does that carbon get counted? So that was the next step, and that would be a tricky project to take on. >> There is some shortcuts I've seen where they have covers, restaurant covers, so number of meals served. And I think you could, I don't know, where it was two kilograms of carbon per adult customer or something like that. I'm going to put up a slide that you have in your PowerPoint, and it compares the carbon footprint of the Denver Zoo to the Philadelphia Zoo, Vancouver and, is it Bristol, UK? >> Yes, I have Bristol and the Victoria zoos in Australia. >> Okay, and you have the absolute carbon emissions, but one of the things that we like to do is, put things on an equal basis. How would you provide some sort of comparison? Number of animals, number of visitors, do you have any thoughts on that? What we used was the size of the zoo. The Denver Zoo is about 60 acres and the Philadelphia Zoo is about 40 acres. So their Scope 1 and Scope 2 emissions were comparable to the ones that l calculated for Denver Zoo. But we were higher, because we are a larger zoo. And I think that you could probably compare zoos based on their size. because generally, the bigger the zoo, the more animals you have. >> It's good to have that kind of comparison, that intensity measure. Now, to actually do the calculations, you've got methane, and you've got refrigerants, and you've got, I don't know, diesel fuel and all kinds of stuff. But somewhere down the line, it all has to be put into carbon dioxide metric tons, how did you do that? There's a tool developed by New Hampshire University, that is called the Campus Carbon Calculator. And it was originally developed to calculate the carbon emissions from a university. However, I converted it to be used for the zoo, because you couldn't say the students were visitors, and faculty is staff, and- >> Or animals. >> [LAUGH] Yeah. And there actually was a section for livestock. >> You know we do this, it's a big exercise, it takes a lot of time and you get a number. But the real value isn't the number, the real value has to be in making improvements. And can you talk a little bit about how the zoo now is using the results of your study, to maybe make some changes. >> It's just a number at the end of the day you come out with, however many metric tons of carbon dioxide, and you need something to compare that to. And you can compare it to other zoos, or now the Denver Zoo has a baseline to compare their future years to. So I mean, ideally, we want to reduce emissions in the future years. And I believe that the Denver Zoo, when I had given this presentation to them, and they were looking at making some changes. Some of the changes that are being implemented now, is they're growing some food on-site for the animals, for the herbivores. So they don't have to transport as much produce from across the US. And that will reduce their emissions for transportation. And they're also creating a database for products commonly purchased, so that they can monitor what is being purchased, to make sure it's coming from a source that is ecologically friendly. And to reduce the amount of shipment coming in. Because if one person, one department purchases a box of pens, and someone else, another, purchases a box of pen, we want that to come in the same shipment, instead of two separate shipments. So that is going to reduce their emissions as well >> That's great, so there's some positive outcomes from the study. An area that we've mentioned in our conversation before the interview, is benefits from the zoo is the same. And it seems to me that this is an untapped area in terms of this whole carbon inventory. We're only looking at carbon emissions, but if we change people's behavior, so that they go home and use less carbon, has this made a contribution? Do you see any of that happening, is that any part of the discussion? Or is that way beyond the sort of tasks or job descriptions, of folks at the zoo to think about their broader impact. >> That is a part of everyone's job description at the zoo. And I think they take climate change very seriously, because their job is to conserve wildlife and their habitats. So they want to educate the public like on why these species are important, how they've become endangered, and what we need to do to help their habitat from being demolished. And I think that right now, they need to create a link between, this is a polar bear and it lives in the Arctic, to you can go home and you can change out your light bulbs, or you can conserve water. And by doing that, you can save the polar bears habitat. I think they need to create that link in the public's mind, and the zoo is a great place to do that. >> I think that's a great answer. Thank you so much. I think that's a wonderful project, I would have never guessed that giraffes- >> [LAUGH] >> Emitted 50 milligrams of methane a year. I guess- >> They do. [LAUGH] >> [INAUDIBLE]. So thanks so much for you time, and I hope that this was a valuable exercise for you. >> Yes it was, it was very valuable and I had a lot of fun doing it. [LAUGH] >> Corette, congratulations on your job at [INAUDIBLE], that's super. >> Thank you. >> Yeah.