How climate change is affecting the Sleeping Bear Dunes

By Linda Alice Dewey
Sun contributor

Air and water temperatures are expected to rise, and lake levels are predicted to decline over time, with longer droughts between heavier rain events. An ecologist explains what scientists believe will happen to our ecosystem in the Sleeping Bear Dunes National Lakeshore area and the single, most important reason behind it all.

“Within the Great Lakes we’re expected to see a change in the frequency of precipitation events and the magnitude of [these] events,” explains University of New Mexico doctoral candidate Lukas Bell-Dereske.

“I am not a climate change expert,” he wants us to know from the get-go, “just a plant ecologist interested in the possible effects of climate change.”

A Michigan native with a B.S. from the University of Michigan, Bell-Dereske conducted an experiment from 2013-2015 in the Sleeping Bear Dunes National Lakeshore to examine how changes in precipitation might affect dune grass and native plants.

He says that the National Park Service is especially interested to see how greater rain events will affect the ecology here. Why? Historically, he explains, rain events have been smaller and pretty evenly distributed. He says that has changed now to larger rain events separated by longer periods of drought, which “are predicted to increase with climate change. We’re already seeing larger rain events than were happening beforehand. So the severity of these swings in precipitation will increase.”

Bell-Dereske claims that what we’re experiencing is unlike anything before. Although the climate runs in cycles, “this is different,” he observes, “because the change is much more rapid than we’ve seen. Outside of some extreme events, the changes in temperature are much faster, and that change in temperature is changing everything else.”

These changes are caused by a change in carbon dioxide (CO²), which is not part of a long-term climate cycle, he says.

How can we tell that this is not part of a long-term climate cycle? “We know that, because we have the ice cores,” he answers, referring to the cores of ice scientists are able to drill down into the ice cap and retrieve. “Within the ice cores we can measure the amounts of CO² concentration, and it’s in layers. We can look at that and the effects.

“And we’re seeing the effects in our lifetime,” he exclaims, noting how many species have become extinct in recent decades, “and the lakes are changing,” he points out.

For instance, Lake Michigan used to freeze over every year like it did the winter of 2013-14. “Without that regular ice cover, some of the temperatures of the lake are changing…”

Not only the temperatures, but lake levels are also changing. “We are predicted to see large drops in the lake levels,” he says, “but since the lake is kind of creating its own weather, this period of high rain that has gone on since the 70s has led to there being a less rapid reduction in lake levels.” Although he reiterates that he is not a climate expert, “I do know something about lake levels,” he says. “Lake levels are predicted to decrease,” he maintains. “We saw that from 1997 until 2013, when it went up, So we might see more oscillations on these longer time scales than what we’ve been seeing historically.”

Bell-Dereske notes that the increases in precipitation are coming in the fall and winter. In fact, he says, “In the spring and in the summer, we’re actually seeing decreases.”

Therefore, gardeners here might consider planting more heat and drought resistant plants. Either that, or we’ll be doing a lot more watering. “And you know, water resources are so important for this region,” he reminds us. Another thing for gardeners to note: “Some of the plants restricted to southern latitudes will be moving up north.”

When asked whether he had heard that the pine trees are migrating north, Bell-Dereske answered, “Yeah, because they’re a more cold-tolerant species and not as good a competitor with the oaks and with some of your southern species that are starting to move up.

On a global scale, when we hear that the earth warmed up another degree, it doesn’t sound like much. But Bell-Dereske explains that this is an average of a degree over the whole planet. It’s pertinent for us in this area, because, for every degree of change worldwide, the more northern latitudes will see a couple of degrees of change, where those toward the equator may not. “It seems like we’re going to see larger increases with every degree of increase,” he observes.

Referring to theories of climate change as “models,” he describes one model which was written in 2010 and published in the Journal of Great Lakes Research by Katharine Hayhoe. It predicts that, if we continue to emit the same levels of CO² that we did in 2010, the state whose current climate would be most like Michigan’s in 2080-2099 is Oklahoma.” The caveat was that it would look that way only if CO² emissions continued at the worst rate Michigan was dumping into the air in 2010.

Thing is, he notes that our emission levels are worse now than they were in 2010, so we might look like the Oklahoma of 2010 sooner than 2080. However, he says, “models are being improved, and this is an old model. Science is so complex.”

So, if it becomes like Oklahoma here, as far as escaping the heat goes, we just go inside and turn on the air, right? Of course, that would result in higher electric bills and more CO2 production. Bell-Dereske says that no one can get away from being affected by climate change. “Global climate change is global. It’s affecting everyone.”

On top of that, he states that 97 percent of climate change scientists blame the spike in CO² and its resultant climate change — which is very sudden, compared to other climate cycles — on human beings.

But aren’t there scientists who do not recognize that there is climate change going on, we ask? “A lot of the studies that are brought up to say, like, ‘This is refuting climate change,’ [are by] a lot of the people who are not experts on climate change but claim to be,” Bell-Dereske points out. “It’s always good to read and try to understand the arguments and understand who is the expert behind the argument. A lot of times, the ones that are shown to be really refuting aren’t as well supported as the ones who are showing that this is human driven.”

Even so, scientists are skeptics. “Scientists have only come to the conclusion that climate change is human driven after decades of research,” he affirms, “and decades of all the data showing that this is connected to humans…

“It’s a buildup of information. That’s what science is. And if ever there is information that refutes that, you have to change your hypothesis. It’s not a sudden conclusion.”

Bell-Dereske would like to see us, as human beings who are cognizant and able to measure cause and effect, “to consider everything we do within the context of how that could affect the environment or the globe.”

This is not necessarily to save the planet. “The one thing everyone talks about is ‘Save the Planet,’” he points out. “It’s not, ‘Save the Planet,’” he contends. “It’s ‘Save Us.’ Because the planet will be okay; but we won’t be okay if we die off.

“So I think that’s the thing we really need to think about — how can we manage our environment and how can we reduce our impact on the environment that they will still be here for our children and their children, right?”