Global warming, and the resulting climate change and extreme weather now appearing worldwide, is arguably the biggest and most challenging threat to the Great Lakes.
(Here is GBF's Commitment To You On Climate Change. This 2 page document was approved in June 2019 and added in September 2019)
The impacts do appear to be alarming. Economically, commercial navigation, recreational boating, recreational fishing, property values and hydropower have already experienced financial impacts due to unnatural extremes in water levels. Beyond our economic interest, scientists agree that there will be ongoing negative impacts from climate change for the health of ecosystems, biodiversity, and water quality.
Climate change can be tackled. Collaboratively, we all worked to reduce The Ozone Hole with scientists, governments, industry and the public. Acid rain was significantly decreased in the 1990s. We need to stop taking a wait and see approach, really fight cynicism, and look towards building climate resiliency and adaptive management for the issues we're already starting to experience, and work collectively to keep global warming from getting worse in the centuries ahead.
Links to climate change effects:

The International Joint Commission (IJC) in its November 2017 newsletter noted these changes that are already occurring in the Great Lakes' climate:
Updates and summary of climate change effects
Impacts to water levels – increasing variability, more extremes
Examples: Evaporation on the Great Lakes
Cool winter, little ice
For the Great Lakes, as huge bodies of open water, with Lake Michigan-Huron being the largest among them in terms of surface area, changes have serious consequences. As noted, ice cover on the Great Lakes during winter has been trending downward over the long-term, with a decline of over 70% over the past 40 years. A full third of the water Georgian Bay can be lost in the winter due to evaporation. When cold prevailing winds sweep from the north or northwest over the warmer water surface , they pick up a lot of moisture, only to drop it again as lake effect snow when they hit land on the other shore or beyond the watershed. This situation helped create some of the prolonged low annual water levels, some unprecedented, we experienced from about 2000 to 2013.
We are in transition between old and new environmental stasis conditions.
Cool winter, lots of ice
In 2014, El Nino, changes in the Jet Stream and a southward shift of the North Polar vortex led to record low temperatures and high ice coverage. In the beginning of the year, an Arctic cold front including what some referred to as a nor'easter travelled across Canada and the United States, resulting in heavy snowfall.
Warm winter, warm water and low ice
In the last few winters (2015 and 2016) we've seen warmer winters combined with warmer water. This leads to little or no evaporation. Weather is weather, and in such years there simply isn't as much water loss in those years.
For more scientific explanation about these last two conditions, please visit this page "Water levels, evaporation, ice coverage and thermodynamics"
Climate and weather - a puzzling relationship.
It's like doing a puzzle without a picture where the pieces can alter and change the puzzle as it progresses over time. It is clear that climate change is effecting weather patterns, but each weather event is a puzzle piece, not the whole puzzle.
In general, water levels are driven by a variety of factors. Some are short term and some are long term. As noted earlier, NOAA describes it this way: “Weather is what you might see outside on any given day, while climate is the average of that weather over a longer time period. Climate is what you expect, weather is what you get."5
For more information, please visit:
The takeaway. We can't just pay attention to the weather.
Remember, many researchers conclude that evaporation levels will increase and will outpace any increases in precipitation in the long-term. This means that Georgian Bay water levels will continue decline over the long term due to changes in the climate, while climate change driven weather will continue to become flashier in the short term and there will be increasing variability.
In its 2012 Upper Great Lakes study, the International Joint Commission determined that there are three main drivers impacting long term water levels in Georgian Bay and Lake Michigan-Huron: (1) climate changes; (2) previous dredging and unexpected erosion in the St. Clair River; and (3) glacial isostatic rebound. While all have contributed, it is currently climate change that was determined to be the main and ongoing driver of long term water levels declines, and extreme variability.
At the same time, the economic consequences to property, infrastructure and ecosystems aren’t slowing down. New thinking, new policies, and new structures that build in climate resilience are needed! Even the investor community is starting to recognize this need that the insurance industry surely understands as illustrated in this article, “Extreme Weather is the New Normal”.
There are solutions, but we need to act!
To mitigate extreme water levels for the short term (the next 100 years), Georgian Bay Forever has been working with AECOM, a world renowned engineering firm, and successfully bringing attention to Increasing climate resilience including using adaptive structures for water levels to decision makers. Read more about climate resilient structural solutions in this report summary link.
Each of us has a responsibility...
at the same time, to help reduce carbon emissions to reach the goal of limiting global warming to 2 degrees Celsius, and prepare for weather extremes. These solutions must become ingrained – the goal can’t be done without making changes in our lives.
Here are some links to things that you can do to reduce the impacts of severe weather events and increased global warming:
- 5 things you can do to reduce your carbon footprint
- Less lawn, more native plants
- Reducing water use while travelling
- Fixing household leaks
Climate change impacts more than water levels.
The effects of climate change will continue to wreak havoc on the water levels of the Great Lakes and Georgian Bay. Doing nothing is too expensive! (See Low Water Blues Summary Report) . We need to pursue short-term mitigation measures for the next 100 years, while simultaneously working as individuals in tandem with all levels of government to ensure that global warming does not exceed 2 degrees Celsius. Because you care about water, please read on about climate change impacts to water quality, habitats and biodiversity.

Warm winter, warm water and low ice
In the last few winters (2015 and 2016) we've seen warmer winters combined with warmer water. This leads to little or no evaporation. Weather is weather, and in such years there simply isn't as much water loss in those years.
For more scientific explanation about these last two conditions, please visit this page "Water levels, evaporation, ice coverage and thermodynamics"
Climate and weather - a puzzling relationship.
It's like doing a puzzle without a picture where the pieces can alter and change the puzzle as it progresses over time. It is clear that climate change is effecting weather patterns, but each weather event is a puzzle piece, not the whole puzzle.
In general, water levels are driven by a variety of factors. Some are short term and some are long term. As noted earlier, NOAA describes it this way: “Weather is what you might see outside on any given day, while climate is the average of that weather over a longer time period. Climate is what you expect, weather is what you get."5
The takeaway. We can't just pay attention to the weather.
Remember, many researchers conclude that evaporation levels will increase and will outpace any increases in precipitation in the long-term. This means that Georgian Bay water levels will continue decline over the long term due to changes in the climate, while climate change driven weather will continue to become flashier in the short term and there will be increasing variability.
There are solutions, but we need to act!
To mitigate extreme water levels for the short term (the next 100 years), Georgian Bay Forever has been working with AECOM, a world renowned engineering firm, and successfully bringing attention to Increasing climate resilience including using adaptive structures for water levels to decision makers. Read more about climate resilient structural solutions in this report summary link. Each of us has a responsibility... at the same time, to help reduce carbon emissions to reach the goal of limiting global warming to 2 degrees Celsius, and prepare for weather extremes. These solutions must become ingrained – the goal can’t be done without making changes in our lives. Here are some links to things that you can do to reduce the impacts of severe weather events and increased global warming:
- 5 things you can do to reduce your carbon footprint
- Less lawn, more native plants
- Reducing water use while travelling
- Fixing household leaks
Impact to biodiversity and habitats – ecosystems
There have been measurable trends in surface water temperatures increases of about 1°C per decade since the 1970s. Even minor temperature changes can have an impact on ecosystems, and that’s one reason why we are working with the University of Guelph to build a library of all aquatic species using DNA barcoding, so that they can be monitored, and results and impacts brought to appropriate decisions makers. More info on this project, at at this link.
We’re concerned we are not doing this fast enough, and we appreciate all donations from supporters of Georgian Bay to help us build this conservation tool. For an example of how climate change impacts one species of fish, Lake Trout, read this article from Fishery Biologist John M. Plumb,PhD, from the United States Geological Survey from our Summer 2017 newsletter. Click here for the article .
Impacts to wetlands: important habitat
We also know from our work with NASA, that when water levels decline over a prolonged period of time, wetlands are impacted - particularly in the southeast part of Georgian Bay. That area is more populated, and wetlands have already been reduced due to development pressures. Further declines because of extreme lows driven by climate change, create even greater risk to fish populations that depend on wetlands as nurseries and places to forage for food. For more information, explore these links:- NASA wetland observation work
- Fluctuations are good for Georgian Bay ecosystems. New extremes are not.
- Learnings from structural intervention in other Great Lakes. Excerpt from Fall 2016 newsletter
- Climate resilient solutions to take the the edges off extreme water levels
- Threats to Georgian Bay wetlands: The interview with ecologist Dr. Janice Gilbert
Phragmites shows how climate change can further help invasive species
Climate change creates better conditions for many invasive species that already reduce biodiversity and outcompete native species. One example is the invasive plant Phragmites. Non-native Phragmites are advancing into Georgian Bay from the South and taking hold in wetlands and developing into monocultures that outcompete native plants. They grow so densely that they do not provide good habitat for native creatures.
Wetlands help mitigate climate change impacts
Ultimately, the wetlands themselves are critical to mitigating some of the impacts of climate changes and their degradation and loss needs to be avoided. For more information on supporting Georgian Bay Forever’s efforts to rid our coastlines of this highly destructive invasive, please visit this link . Man made climate change is changing the habitat and environment for our native species very quickly, and it threatens so many of them. We need to all work together on quick and effective monitoring of these ecosystems as the impacts of climate change continue, so these results can be brought to decision-makers and policies enacted to protect against the more severe disruptions of the biodiversity of species in Georgian Bay.Effects on the water we drink and swim in, and on the living space of our aquatic animals
Waste and Stormwater Overflows
Our future promises flashier storms with shorter bursts of greater precipitation.
There has been 37 percent increase in more extreme precipitation events since 19587 . Wastewater and stormwater infrastructure designed and built 30 to 100 or more years ago did not predict this new unpredictability, or in some cases warnings were ignored. We are starting to feel the impacts.
We noted with concern this headline in the Midland Mirror in the summer of 2017 “Excessive rain causing Midland to dump raw sewage into Georgian Bay”. The article mentions that over 1.3 million litres of raw sewage has ended up in Georgian Bay from the Town of Midland in the past four years. 8. Clearly, we don’t want to be swimming in sewage. To get a further sense, read the is 2 page article " Water Quality Issue: Sewage Overflows Into Georgian Bay" by Sara Carter, a member of our Communications Committee team.
Algal blooms
Another impact on water quality from climate change is increasing risk of more algal blooms. While some algal blooms are natural and have been observed historically, there are places in Lake Erie that are experiencing greater outbreaks, some of which are toxic. Microcystin is a neurotoxin sometimes produced by blooms of freshwater algae. 10 In the summer of 2014, 500,000 people in the city of Toledo were left without drinking water because of toxins in their drinking water from a toxic algal bloom in Lake Erie. Large intense rainfalls produce a lot of untreated run off containing nutrients like phosphorus from fertilizers used agricultural lands and other pollution from hardened cityscapes the flows into our Lakes. Phosphorus entering the lake helps algal blooms to grow.It's bad for us, and it's bad for many species.
Warm water reduces the cool water fishes environmental quality and improves habitats for invasive species which we talked about in the impact to ecosystem segment. Not only, are these impacts terrible, but reduction in water quality from stormwater run-offs and sewer overflows are clearly more hazardous to the aquatic creatures that have to live in the resulting pollution. Please see this article and video from Ecowatch; which shows a salmon struggling for life in a polluted stormwater run-off.
Watch this 16 minute video for suggestions on how you can adapt your property to the new realities. Presented by GBF’s Executive Director David Sweetnam.
We would also very much welcome any suggestions, or experiences you have had with making adaptation changes to your property. Please email info@gbf.org.
There are solutions.

Ideas from GBF's David Sweetnam. 16 minute video originally presented in summer 2020Click here to get the video.

Eat for human and planetary health
(Update Jan 2019). Donna Mitchell writes a blog post: choosing to eat more plants and less meat, and to waste less food, is one of the most effective ways to reduce your carbon footprint while also improving personal health.Click here to read the article.
5National Oceanic and Atmospheric Administration, “What is the difference between weather and climate?” [http://oceanservice.noaa.gov/facts/weather_climate.html] December 7, 2015. 6Some of the more recent materials we are looking at include the EPA's Climate Change and Risks Analysis Report(2).This report places US number at 61% loss of cold water fish habitat (without mitigation). The 28% GBF reported based on coastal wetland inventory changes modelled in is well within those bounds. The World Wildlife Fund currently is reporting between 45 and 30% of habitat loss for cold water fish (retrieved Feb 2016). http://www.nwf.org/Wildlife/Threats-to-Wildlife/Global-Warming/Effects-on-Wildlife-and-Habitat/Great-Lakes.aspx 7From IJC newsletter Nov 15, 2017 “IJC Presents Findings for Climate Change, Crude Oil Transport, Water Quantity and Quality at Healing Our Waters Conference”. From the IJC Great Lakes Water Quality Board summary of findings. http://ijc.org/greatlakesconnection/en/2017/11/ijc-presents-findings-for-climate-change-crude-oil-transport-water-quantity-and-quality-at-healing-our-waters-conference/?mc_cid=d141b53497&mc_eid=8375621011 8Mendler, Andrew. Excessive rain causing Midland to dump raw sewage into Georgian Bay. Midland Mirror. Simcoe.com. Retrieved Sept 27th, 2017 at https://www.simcoe.com/news-story/7526795-excessive-rain-causing-midland-to-dump-raw-sewage-into-georgian-bay/ 9Leaders: $271B Needed for Creaky Great Lakes Water Systems. AP, US.News. Best States. Sept. 21, 2017. Retrieved at https://www.usnews.com/news/best-states/minnesota/articles/2017-09-21/leaders-271b-needed-for-creaky-great-lakes-water-systems 10https://www.ecowatch.com/toxic-algae-bloom-leaves-500-000-without-drinking-water-in-ohio-1881940537.html 11
Nahlik, A.M. and FEnnessy M.S. "Carbon storage in US Wetlands." December 2016. https://www.nature.com/articles/ncomms13835. Retrieved in October 2017. Other references:
- http://www.landlinemag.com/Story.aspx?StoryID=71089#.WfImKYZrylM
- From IJC newsletter Nov 15, 2017 “IJC Presents Findings for Climate Change, Crude Oil Transport, Water Quantity and Quality at Healing Our Waters Conference”. From the IJC Great Lakes Water Quality Board summary of findings. http://ijc.org/greatlakesconnection/en/2017/11/ijc-presents-findings-for-climate-change-crude-oil-transport-water-quantity-and-quality-at-healing-our-waters-conference/?mc_cid=d141b53497&mc_eid=8375621011
- Moudrak, Natlia." Extreme Weather is the New Normal". Oct.5, 2017. http://www.investmentreview.com/analysis-research/extreme-weather-is-the-new-normal-7891. Retrieved December 2017.
- Salmon struggling. https://www.ecowatch.com/car-pollution-coho-salmon-2500241142.html Retrieved December 2017.
- The Associated Press. "U.K. engineers launch ‘sewer war’ against giant fat blob" https://www.thestar.com/news/world/2017/09/12/uk-engineers-launch-sewer-war-against-giant-fat-blob.html. Sept 12, 1017. Retrieved December 2017