How Will Climate Change Impact the Great Lakes?
Below: A Lake Ontario shoreline
Lower water levels. Warmer air and water temperatures. Less winter ice cover. More extreme storms.
Scientists believe this is the future of the Great Lakes basin as it begins to feel the impacts of climate change.
Al Douglas is the director of the Ontario Centre for Climate Change Impacts and Adaptation Resources, an agency tasked with communicating the science of climate change and its impacts. He recently spoke to Rust Wire about what residents of the Great Lakes region should know and understand about climate change. Our conversation has been edited for space. (To read more on this topic, see here, the Great Lakes Regional Assessment here, a report from the Union of Concerned Scientists here or the Climate Change on the Great Lakes project here.)
Editor’s note: We first met Douglas through the Institute for Journalism and Natural Resources’ Great Waters Institute, which educates journalists about environmental issues surrounding the Great Lakes. -KG
RW: “Can you start out by summarizing some of the changes and trends that you and other scientists have seen so far in the Great Lakes basin?”
AD: “It varies, because the basin is so big, it varies from place to place. The changes in climate vary a bit as you move from location to location around the Great Lakes. But there have been noted increases in temperature, since the last – well, since they have been recording temperatures, – changes …of around two degrees Celsius in some areas and a little less in other areas. Those are the average annual temperature changes that we see in different parts. We tend to also see a bit more variability that exists with the weather. We have highs and lows, and the lengths of time that we spend in those highs and lows has been changing as well…there are also the extremes. There is lots of evidence of large storm events that have occurred in the basin, that have caused problems for communities in the Great Lakes.”
RW: “When you say ‘extreme events’ do you mean something like a large thunderstorm or snowstorm, kind of like a ‘100-year-rain’?”
AD: “That’s right, yes. That’s a good way to communicate it, people can understand those terms…But you have to be a little careful with the words, because it is not just a one-in-100 year storm, it is the odds that a one-in-100 year event will occur each year; that’s the way to look at it. The intensity of those events seems to be at a higher level that we are used to and in some cases, they seem to be popping up more often in different locations.”
RW: “With the differences in temperature you mentioned, two degrees Celsius doesn’t really sound like a lot to most people. Why is that important?”
AD: “To the common person, I think that is a fair response. People don’t usually understand the magnitude of those temperature changes or even the associated average annual precipitation. The temperature and the precipitation are presented, both of those are presented as annual averages. That’s the data we’ve got.…The magnitude of that number is not very large…The difference in temperature from when we were coming out of the last ice age, and now, given that it was only around five degrees Celsius, that’s significant. That’s half of what that temperature change is. It has taken 10,000 -12,000 years to experience five degrees Celsius, and ….when you compare it to that number, it is quite significant. And again, that number does not capture the variability; it does not capture the extremes, so you are only looking at one aspect of climate change.”
RW: “My understanding is that one result of climate change will also be lower Lake levels. It sounds counter-intuitive, since there will also be more precipitation. Can you explain that?”
AD: “You’ve got warmer air temperatures, which also leads to warmer water temperatures. So, you’ve got a heating of that system. It holds the heat an awful lot longer. So warmer water temperatures, plus warmer air temperatures means that there is shortening of the ice cover season. And we depend on the ice cover –the freezing of the Lakes- to try to control the evaporation from the Lakes. So where you’ve got a shorter ice cover season, you could potentially have larger evaporation.”
Below: A Great Lakes ship passes through the locks at the Welland Canal in St. Catherines, Ontario.
RW: “And lower water levels impacts shipping, boating, recreation, a lot of things, right?”
AD: “Changes in water levels in the Great Lakes has a number of different impacts. Shipping and navigation – it is difficult to haul some of the large loads that they have, trying to get through the system. Tourism and recreation- there are aesthetic issues, beach closures, things like that. Fisheries- changes to the species, there are cold, cool and warm water species of fish. Where you’ve got certain populations now, and those could change into the future depending on the water temperature. Energy and industry, human health, munipicalites even consumption in some areas, all of this can be impacted by water levels.”
RW: “I think of lot of folks, particularly in the Midwest, mainly hear about rising sea levels, so they don’t really think climate change will impact them. How does climate change in the Great Lakes basin impact, say an average person living in a place like Cleveland, Milwaukee or Detroit? What changes might a person who uses the Lakes recreationally see? Why should they be concerned?”
AD: “You need to communicate the quality and quantity of water in the Lakes to be able to convince them that it is important to pay attention to…. There are huge, huge, economic benefits that are derived as a result of the waters in the Great Lakes. People often don’t understand that or appreciate it, or underestimate it. It’s a huge part of our economy. There are so many sectors- when we were talking about the water levels of the Lakes, and the number of different sectors that are impacted, these communities are dependent on water in the Great Lakes, water quality and water quantity. You know, as things change, as temperatures increase, as we see these changes to the system, we have to understand that is going to affect the economies in our communities. In addition, and this is so often undervalued or underappreciated, is the fact that it is affecting the ecosystem, the health of the ecosystems. The plants, the birds, the fish, and the intangible benefits that we derive from the biodiversity and ecosystems of the Great Lakes. As things change, so do they have to change and adapt. And where there are limits to adaptation and they are not able to adapt, we have this loss of diversity and shifting of species.”
RW: “Is there anything I haven’t asked about that you would like to mention or highlight?”
AD: “I suspect that the majority of your readers will be in the US. So, it’s worth noting the efforts of the EPA and NOAA right now and what they are doing in responding to climate change. I get news articles and different reports that come across my desk almost every day that show there is a lot more activity going on, in the States, both from the EPA and NOAA. That is very, very encouraging for me to see that happening at that level in the US…. To me, it’s that we’ve moved beyong the discussion about whether it is happening or not to ‘what sorts of activities do we need to do to make sure we’re prepared for this and able to respond to this.’”
Below: The Toledo skyline along the Maumee River, which flows into Lake Erie nearby.