How is climate change impacting the Great Lakes?

| 30 minutes | Media Contact: University Communications


How is climate change impacting the Great Lakes region? 

Guest: Zach Johnson, climate scientist and assistant meteorology professor at Central Michigan University


In this podcast episode, host Adam Sparkes interviews Zach Johnson, a climate scientist and meteorology professor at Central Michigan University, about the impact of climate change on the Great Lakes region. Johnson explains that climate change refers to long-term changes in the Earth's climate system, which can be observed over decades and centuries. He discusses how climate change is causing a reduction in snowpack and ice coverage on the Great Lakes, leading to changes in stream flow, lake levels, and coastal erosion. Johnson also highlights the potential impacts on winter sports, agriculture, and the energy industry. He emphasizes the need for adaptation and risk assessment in the face of climate change and discusses the importance of interdisciplinary collaboration in addressing this global issue. The conversation touches on the role of the Great Lakes in moderating regional climate, the importance of water quality, and the interconnectedness of various scientific disciplines in studying climate change. Johnson concludes by emphasizing the need for collective action and integration of different perspectives to effectively address the challenges posed by climate change. 




Adam: How is climate change affecting the Great Lakes? Welcome to The Search Bar. You've got questions. Let's find some answers. I'm your host, Adam Sparkes, and today we're chatting with Zach Johnson, climate scientist and meteorology professor at Central Michigan University. Hi Zach, thanks for coming in and talking to me today. I'm excited for us to continue the conversation we had previously about El Niño and talk a little bit about climate change in general and how it might impact the Northern Midwest or the Great Lakes states. I thought it would be cool if you could just introduce yourself professionally, and why that’s an area of interest for you, and what your expertise are.

Zach: Yeah, thanks for having me back. So, where to begin? Well, I did my PhD at Utah State University, did a post-doc at Purdue University — both in climate science and also in atmospheric science. So, after that I came here to CMU. I'm an assistant professor of meteorology. They hired me on, kind of more as their climate guy. So, my research really involves the climate system, specifically about the El Niño Southern Oscillation, which is what we talked about before. But I also do research in climate change and, kind of, climate risk also. I also teach classes. I teach a class called Climatology and Climate Change right here at CMU. I also teach a class on atmospheric modeling, emphasizing climate, but also emphasizing weather. My background's really, I'd say, interdisciplinary in climate science and also climate change.

What is the definition of climate and climate change?

Adam: So, that's a lot of the word climate, which is perfect because I think it would be helpful to talk a little bit about what climate change is, and what it isn't. It's definitely a term that's in the zeitgeist. We kind of kicked global warming out because that wasn't the right vernacular, if you will. And we use the term climate change now. But kind of tell me how you view it, and then maybe give us an example of times when, maybe, it's kind of mischaracterized.

Zach: Climate is someone's personality while weather is someone's mood, right? Climate is to personality as weather is to mood. Our mood changes from day to day, but your personality is kind of stuck with you throughout your life. And so, when we talk about climate or climate change, we're really thinking on long timescales. We're integrating all of the high frequency weather, maybe all the storms we have in the winter or over the course of a decade, and we integrate that and we do some sort of statistical analysis, and that's how we come up with climate. And so, we see our climate changing, we see our earth warming. Not when we look day-to-day, but when we look over decades, over centuries, we see this warming effect. And so, I think it's really important to think of climate change as not day-to-day, or even month-to-month; think on terms of decades and years. And so, climate change really is this idea that the earth is warming. Most of Earth is warming. We changed the term from global warming to climate change because not everywhere is warming at the same rate. There are actually a few locations on the planet that have cooled a little bit in the past a hundred years, but if we average out the entire — entirety of the earth, the earth is warming, and our climate is changing.

How does climate change impact the Great Lakes region?

Adam: Like one in ten — this is like 2021… I'm quoting ProPublica here, so this is not me. I don't know stuff like Zach does. In 2021, one in ten homes were affected by some sort of climate event, some sort of climate change thing. I think what makes that interesting for us here, in the Great Lakes region, is [that] we're kind of viewed as a little bit insulated from some of these things. But that doesn't mean that they're not happening. What type of stuff are we seeing in Michigan and in the Great Lakes regions in general when it comes to climate change?

Zach: That's a really good point. The most obvious aspect of climate change that we could see in the Great Lakes is this reduction of snow. We could look back 30, 40 years ago, 50 years ago, and we would see the snowpack was pretty far south. And, if you look at the snowpack in the winters now, it's kind of retracted towards the north. So, we see this effect on snowpack. Which then in turn impacts, maybe, stream flow into rivers when snow melts, and then that water eventually heads back into the Great Lakes. And so, when we have less snow cover, we're altering this kind of seasonality of, maybe, fresh water that goes into tributaries and lakes. So we see that effect pretty greatly. We also see that there is less ice coverage on the Great Lakes.

Adam: A lot less, right?

Zach: A lot less. You could really clearly see that from satellite images, just looking at every winter over the past 50 years. You could see the extent, the ice extent over the Great Lakes, has reduced significantly. And so, those are two, kind of, aspects, I think, that we could see obviously happening here in the Great Lakes. But there's also kind of more subtle things that are occurring. So, we could start thinking about winter sports. We have less snow, maybe the ski industry, which is pretty important here in Michigan in terms of tourism and other things like that — the snow is becoming less and less, so that's impacting economies. We could see it, not just in economies that are reliant on snow, but maybe in the energy industry, or in agriculture. I could go on and on.

Adam: Our brains aren't super hardwired to deal with very slow rolling violence, which is kind of what climate change is. It's not getting socked in the jaw. It's getting boiled, like the frog getting boiled in water. Like, really slowly having the temperature turned up on you, “Haha,” figuratively and literally, I guess. We're really super good at being fight or flight. I'm reacting to — Zach picks up the coffee mug and he's going to throw it at me, or he is going to splash the water at me. I might duck, I might throw my coffee mug. But if you just, kind of, tip it over during the interview and the water just slowly tips towards me, I'm much less likely to have an appropriate reaction to avoiding getting wet, or whatever. I feel like climate change is a little bit of that. So, talking about where people get hit, those anecdotes, I think, hit home, especially when the math bears out that those anecdotes are representing something real. So, if you live in the state of Michigan and last year ice was not safe to ice fish, that's directly a result of these types of climate change.

Zach: Yeah, I don't even know where to begin with this, but… Yeah, humans, our nature, we do react to things that happen fast, but things that slowly trickle — our subconscious, we might adapt subconsciously, or we might have to make adaptation measures to adjust. But as humans, we are very good at adapting. Plants and animals? Maybe not so much, being able to adapt. And I think that's one aspect of climate change, in terms of our ecosystem and our environment, that we might notice in the future. For instance, fishing, a lot of fish are cold-blooded. They prefer a certain temperature. If the lake is warming, we are going to alter their environment. And the question is, will they adapt or will they die off? And I think that's a really important topic in terms of ecosystems and how climate change can impact that.

Adam: What I'm thinking is: there's just such a downhill effect, even just economically. You had mentioned snow and ice, right? Yeah. You can't ice fish and you can't ski. And I think maybe for some folks who don't ice fish, or don't ski, or don't, maybe, snowmobile, we are not thinking about that downhill effect. There are places in this state where when snowmobiling season comes — or hunting season or ice fishing season comes — there's businesses — there's bars, there's motels — that are making a tremendous amount of their annual income on the influx of people who are coming to recreate. But also, ice cover and erosion is like a massive thing too, because ice cover on large bodies of water… it reduces the amount of erosion at the surface that we see during those winter months. And you're seeing, all over on the bigger lakes, homes that are either falling into the lakes or can just no longer reliably be as close to the water as they had been for maybe 20, 30, 40 or 50 years. They're literally falling into Lake Superior, literally falling into Lake Michigan.

Zach: Yeah, that's a really important topic moving forward. Coastal erosion, or coastal ecosystems changing because of climate change. And so, that is a topic that impacts a lot of industries. As a climate scientist, I'm interested in the physical mechanisms and the predictability of our climate, but I also have to remember that this has impacts to ecosystems, to humans. So, lake levels are [a] really important concept of climate change. I think in the future, the projections suggest a lake level that's becoming — lowering due to climate change, and yeah, that's going to impact coastal erosion. It's going to impact coastal ecosystems, fishing, you name it. It really is something that we're going to have to adapt to or it's just going to impact humans as a whole here in the Great Lakes region.

Adam: And we're seeing bigger algae blooms, too, in the Great Lakes, which is — mischaracterizing this, but a couple of years ago it started to be this massive Lake Erie algae bloom that they were following around. You could just see it from a helicopter. It was just this big neon-yellow algae kind of floating through the area. And that, you know, it's certainly an indication that this stuff is happening, but who wants to go out and be in that lake on their boat. If you need to bring it down to a simple level for people to understand and empathize with, like, “Ew,” I guess.

Zach: Right, kind of gross. So, a warming lake will promote more algae, but it also promotes kind of more lake borne viruses and diseases. So that's another component to human health that I think is really important for climate change. Michigan is surrounded by Great lakes. This is a really important question. How is climate change going to impact lake ecosystems, lake erosion, lake level, lake ice extent? There's so many different angles to look at this, and that's just thinking about lakes. We could also think about ecosystems here on land. How are animals and crops and vegetation and trees — how are they going to adapt? Are they going to adapt? Is the forest in the U.P. of Michigan — is that going to be impacted by climate change? When you start talking about all these different aspects, it's really important for scientists, for environmental scientists, for ecosystem scientists, for climate scientists to understand: how is our environment going to change? And I think it's also important to remember that, yeah, our environment's going to change here in Michigan, but it's also going to change all over the world, and that's going to impact countries differentially. Here in the United States, in Michigan, we are a first world country, but there are other countries that are not going to be able to adapt as easily, maybe because their economies aren't as great. So, it really is this huge issue, and it's going to be one of the challenges that humans are going to face in this coming century.

How is climate change impacting Michigan communities?

Adam: From a municipal level, what are some of the infrastructure things? Again, I'm sticking with the Great Lakes region right now. And again, I want to acknowledge that we’re a little bit insulated from this where we're at geographically. Like Florida, Texas, a couple of years ago Houston was literally underwater after one of the hurricanes. We're not getting that. But we are getting underwater sometimes. What do we need to do to be better prepared for that type of thing? We're doing bigger storm surges. What can local governments do?

Zach: Yeah, really good question. So, climate change, it's a scientific topic that we're still exploring, but there is some consensus that the extremes that we have, in terms of weather and climate disasters, are going to become greater. There's going to be a higher frequency of these extremes in the future. So when we think of extremes here in Michigan, we're thinking maybe tornadoes, severe thunderstorms, flooding events, things like that. In the future, we think that this is going to become more prevalent, the frequency of these events. So, when we start talking about cities and can we mitigate this risk — are there going to be more floods in, maybe in these metropolitan areas, like Detroit, Lansing and Grand Rapids? Are rivers going to flood because we have extremely heavy rain events that are occurring more frequently? And these are the questions that we have to, kind of, understand, and it's still a part of the field that we're still trying to explore and understand. So, it's really interesting for me. So, I get to run climate models, atmospheric models, and try to understand the future climate and maybe whether we're going to have more floods, for instance, here in Michigan.

How can we mitigate the effects of climate change?

Adam: Are you all hearing more voices from these communities and from these affected governments, as far as, “We need to better understand what might happen to us,” either in the future or tomorrow. “We don't want this to happen again?”

Zach: Yeah, we are hearing a lot more in different communities than maybe we did in the nineties and early two-thousands. I think the debate whether climate is changing is over, right? Climate is changing. There is extremely strong scientific evidence. So now, we need to think about, as humanity, how are we going to overcome the potential negative effects of climate change? How are we going to adapt? How are we going to assess risk? And I think there's this collective idea that climate is changing and how are we going to adapt and how are we going to assess risk? And I think that's really something that a lot of different industries are trying to figure out — whether you're in agriculture, maybe wind energy or the energy industry. Electrical grids, obviously, are going to be impacted by climate. Tourism, local economies, and so forth and so on. So there's this collective idea that climate is changing. How are we going to mitigate it? How are we going to assess risk? And I think that's not an area that I'm an expert in.

Adam: Well, you're not a civil engineer.

Zach: Not a civil engineer.

Adam: You could get on it though.

Zach: I could get on it. I could get on it.

Adam: It does seem pretty obvious that every dollar not spent on making us either more sustainable or being prepared for things as we become less sustainable — every dollar spent there, it seems like we're probably going to be paying for that threefold later on if we're just getting flooded, if we're just eroding all of the shores. I mean, if Louisiana is 20% underwater by 2050, how much more expensive is that going to be than, I don't know, getting them on tidal power down there or something along those lines?

Zach: Whenever we advance science, the potential impact to our economy, usually, is going to be beneficial. I'm thinking in terms of the space race. At the time, we were trying to get to space, and after the fifties and sixties and the seventies, the technology, the improvements in our scientific understanding in so many different fields kind of progressed us to where we're at today. And I think climate change, it's this global issue. The space race wasn't necessarily a global issue. But the idea of understanding our climate, mitigating risk, trying to adapt, I think, as humans, is going to be — yeah, initially, it's going to cost some money.

Adam: Probably a lot.

Zach: A lot of money. And it's something that we we're doing right now, especially here in Western countries. So, there's this differential impact. But here in the United States, we're taking measures to adapt. There's wind energy, solar energy. We're trying to become energy independent. We're trying to get to net-zero carbon emissions. The investment is going to be a lot. I think the outcome and, in the future, the impact, I think, will be really beneficial down the road, just like the space race was in terms of technology.

What is the current focus for addressing climate change?

Adam: The tough part [is] when you're having a conversation with somebody — let's not even talk about people who are completely denying it — but someone who's just doesn't see the urgency. I want to be able to go, “Yeah, but you want this thing?” And it's sometimes that fear we were talking about earlier of just your great grandkids not being able to live in any of these coastal cities that exist now seems so intangible for people. What else is there? Is there a thing that you could think of, or that you would want, that would motivate people?

Zach: Yeah, that's a really good question. I think that's everyone's question. We want to be able to answer that. I think what Tesla was doing, it was radical at the time, maybe 10 years ago or 15 years ago, I'm just guessing on dates. But now, you see a Tesla all the time. The range of these cars is 300, 350, 400 miles now. We do need something like that, that's radical right now to be able to progress. So the whole reason we have climate change to begin with is because of greenhouse gas emissions for our energy. It's something that we rely on. It's what brings us — it's what’s bringing us into the future. And so, for instance, what Tesla did with the battery, I think there's a lot of potential there. There's a lot of work being done in terms of storage of energy, trying to get away from greenhouse gas emissions, trying to be more carbon neutral. We have wind energy, we have solar. There's hydroelectric generation. But there's still a lot of power plants that are emitting greenhouse gases. And I think, right now, the battery industry, what Tesla's doing, what other companies are doing with batteries, I think, has some potential in the long run to really help us free ourselves and become energy independent and become carbon neutral. And I'm hoping, and I really hope, that this kind of radical idea now becomes a reality in the future in terms of battery, not just in first world countries, but also in other developing countries where a lot of the carbon emissions are being produced right now.

What is the significance of water quality and the Great Lakes' impact on climate?

Zach: Fresh water. We're really lucky, we have the Great Lakes. It's the largest freshwater resource in the world.

Adam: By far, too.

Zach: By far. And so, it's something, as locals, we really need to protect that, for the sake of humanity. And so, I think the question becomes, how can we keep water quality good? How can we make sure that there is enough water — and there will be — but it really becomes kind of a water quality issue, like we've talked about before. Warmer waters, maybe, can produce more algae, more airborne viruses, more lake borne viruses. It could reduce water quality when there's more smog in the atmosphere, when there's more negative impacts of climate change. And so, thinking about the Great Lakes as a fresh water source, I think water quality is something we need to really, really care about.

Adam: Let’s talk a little bit about what those big lakes are doing in terms of the climate of… we’ll just call it Michigan for now. But I think what's interesting is thinking about what a massive body of water is physically doing when it comes to the temperature or the climate of a region, right? 

Zach: Yeah. 

Adam: I don't know that everyone understands that. So, I was wondering if you can give us — give me that ninth grade explanation of water versus land when it comes to storing carbon, storing heat. What's happening for those of us who live near these big lakes?

Zach: Yeah, great question. So, I think the best example is to think about when you're boiling a pot of water on a stove. It takes a long time to boil a pot of water, which means there's a lot of heat and energy that needs to go into your pot to boil the water. So, there's a lot of heat storage just in a couple cups of water. Now, imagine the Great Lakes; [it’s a] much larger water source. So, the amount of heat content that could be stored in the Great Lakes is kind of unfathomable, and it's even greater for oceans. For instance, for the Tropical Pacific, my research in El Niño and La Niña. But when we think about Great Lakes regionally — so it's this large source to store heat, but that heat can also come back out to the atmosphere. And that's kind of how the Great Lakes can affect regional climates, through evaporation. And then that can alter kind of our regional weather patterns. So, for instance, I think a lot of us are familiar with lake effect snow in the Great Lakes. And it has to do with the water temperature, the lake temperature. So if the lake temperature is warmer, that's going to impact snow rates, for instance, from lake effect snow. And so, the question as a climate scientist, from my point of view, is how is climate change impacting the Great Lakes, and then can we see that impact subsequently on our regional climate and weather? And I think we can, in terms of, maybe, more rain, for instance, more snow, for instance, coming directly from the Great Lakes. Not the large-scale weather pattern that's more impacted by climate change. And so, yeah, the Great Lakes do have a large impact regionally, and there's folks here at CMU that are working on that specific issue.

Adam: If there's dramatic effects on the quality of the water, the temperature of the water, it's going to have a dramatic effect on this city that's right on that water that has been stabilized by that giant insulator that they've been up against all these years.

Zach: You are 100% right. So, the Great Lakes act as a — they kind of moderate temperatures, for instance, right? Because there's this really large body of water, it takes a long time for water to cool down and heat up, as we just talked about, the energy required.

Adam: Like the stove. Yeah.

Zach: Right, so when winter comes, the Great Lakes are relatively warmer than the air temperature, and that's one of the main reasons why we have lake effect snow. But it also helps moderate temperatures. So, I think folks in Wisconsin and Iowa and Minnesota, they're going to have much stronger cold snaps than we do here in Michigan. But again, if you average out all the temperatures throughout the winter period, the climate doesn't look that much different compared — in Minnesota and Wisconsin compared to Michigan. But, I think, when a cold snap comes in, it might be negative 10 in Wisconsin, and maybe it only gets down to zero here in Michigan. So yeah, the lakes do moderate temperatures quite a bit and have a huge impact on the regional climate. So, it's really important in terms of climate change. When you think about, “Okay, the lake has warmed a couple degrees Fahrenheit in the last 50 years, this is a fact. How does that influence our regional climate downstream?” For instance, downstream of Lake Michigan where we have Grand Rapids, Lansing and Detroit. How can we kind of quantify that in the future? Is that going to cause more precipitation? Is it going to help moderate temperatures in the winter? Is it going to make temperatures warmer in the summer? And these are topics that we have scientists here, professors and PhD students, working on those specific topics.


What is the potential impact of rising water temperatures on Great Lakes ecosystems?

Adam: All of this stuff is tied together. It's such a massive web. Like, what you all are looking at in the climate side, this is directly kind of symbiotic or correlated, I guess, with the people who are looking at it — the invertebrates and the plant life, the little ones. That's a whole area of study that we have here, and we have it in universities across the world where you're kind of going, “What happens when these small life forms stop being the carbon store that they are [and] what replaces it in the water?

Zach: Right. I mean, phytoplankton and these small fish, they're the bottom of the food chain. So, once you unpack, that's going to reverberate across the food chain and across ecosystems. So, this is a really important topic, in terms of phytoplankton.

Adam: Well, and it goes with El Niño too, right? Because they tend to like cooler water. We should establish that: warm water kills plankton.

Zach: Yeah. So, like we've talked about, it's an important source for the food chain, the bottom of the food chain, but also helps reduce our carbon — plankton. And like you said, they die [and] eventually go to the bottom. And so, that carbon gets stored deep in our waters. And this is an area that I'm not an expert by any means, but it is an important topic. So, when we think about climate change, we're really integrating all the components of the earth system: the land, sea ice, ocean, the biosphere, the hydrosphere, the atmosphere. And when we start to think about that as this integration of all of these components of the earth system, and the biosphere, it really becomes this topic that so many different scientists and so many different people can look at and try to understand. And I think that's really important around the globe, but also important here in Michigan because of the Great Lakes and it being a really important freshwater resource.

Why is an interdisciplinary approach important to addressing climate change?

Adam: Yeah, I agree. And I also think — let me bring it really close to home. 

Zach: Sure, yeah. 

Adam: It's important for places like where we work, here at Central Michigan University. It's important for universities, because as we realize how interconnected all these disciplines in science are, our young scientists need to come out knowing that, “I'm not going to be a climate scientist in a vacuum.” And that's not to say that climate scientists have existed in a vacuum up until now, but more and more and more, you have to be able to link arms with people who are in adjacent scientific fields so that you can put that research together and start to realize what a big, interwoven system we have here as a planet. I mean, more and more and more that's happening. I know it happens here, and I know it happens at larger institutions and at bigger funds as well.

Zach: So, here at Central Michigan University, we are trying to become a leader in this integration of many disciplines as it relates to climate science and climate change. And I think as high school students and college students start to understand that really we need to integrate all of these different disciplines, I think it becomes a really fascinating, kind of, idea to study in the future. Of all these different disciplines. And it's not just that, it also goes back to economies, industries, back to how society thinks about climate change. So we could start bringing in communication and psychology. So really, I think climate change is going to be one of the greatest issues that we face as a society. It's not just limited to meteorology and climate science. It's really this kind of holistic idea that many different disciplines need to understand it from different angles.

Adam: Yeah, you're right. I mean, you need the engineers, and you need the humanitarians, and we need the people in liberal arts to have attention towards this. I mean, I think we have a degree path here that's in public administration that is — it's not public administration, there's a more specific path — but that just deals with public policy and environmental impact. And these things are important. That person's going to have to work with a climate scientist, who's going to have to work with the engineer to builds the solution that mitigates the thing that the climate scientist maybe pointed out, and that person from that public admin has got to get funded. We all are kind of in this together.

Zach: And so, for instance, just to touch on this real quick, I teach a climate change class, Climatology and Climate Change, here at CMU, and we have many different majors. Undergrad students have different majors, ranging from ecosystems science, environmental studies, environmental science, meteorology, and then many other disciplines in the liberal arts, communication, you name it. And I think folks are really starting to understand that this is becoming a — really an issue that we can research and study and analyze from so many different angles. That's so important, too.

Adam: Yeah, you're right. There's just a million places from which you can observe what's happening, right?

Zach: Yeah, yeah, exactly. And sometimes, myself, I'm studying the physical mechanisms. I'm going into the hardcore physics and math and working in climate models. I sometimes forget that this is, really — I'm just one aspect of this. And really, for the next foreseeable future, for the next a hundred years, this issue is going to have to be looked at at many different angles, not just my specific, narrow kind of idea. It's obviously important to understand the physics and to predict how warm is it going to get, but then the impacts, the risk, the mitigation, the communication becomes more of a multidisciplinary issue.

Adam: All these different disciplines can have some focus on climate change at some point if we really stop and think about it. 

Zach: Yeah. 

Adam: That's amazing. I wish we could go on, I think I could write 10 more questions here, but I'm going to wrap it up. Zach, thank you so much for giving me your time.

Zach: Yeah, thank you so much. It was a pleasure to be here, and I think we had a really good conversation, so.

Adam: Awesome. Alright, until we meet again. 

Zach: Alright, sounds good.

Adam: Thanks for stopping by The Search Bar. Make sure that you like and subscribe so that you never have to search for another episode.

The views and opinions expressed in these episodes are strictly those of the host and guest speaker.