Climate Change Connections: Minnesota (Lakes)

Climate change is impacting all regions and sectors of the United States. The State and Regional Climate Change Connections resource highlights climate change connections to culturally, ecologically, or economically important features of each state and territory. The content on this page provides an illustrative example. As climate change will affect each state and territory in diverse ways, this resource only describes a small portion of these risks. For more comprehensive information about regional climate impacts, please visit the Fifth National Climate Assessment and Climate Change Impacts by Sector.

On this page:

• Key Messages
• Introduction
• Climate Impacts
• Taking Action
• Related Resources
• References

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Introduction: Minnesota’s Many Lakes Support Diverse Ecosystems and Economies

Minnesota is home to more than 11,000 large lakes. The state features nearly 34,000 miles of shoreline,¹ which includes part of Lake Superior, the largest freshwater lake in the world. These lakes support hundreds of species of fish, waterfowl, and other wildlife. The lakes are an important natural resource and play a key role in the state’s culture. Residents and visitors enjoy spending time on the water year-round. In winter, the frozen lakes are popular destinations for ice fishing, hockey, skating, and snowmobiling. As climate change brings warmer temperatures to the “Land of 10,000 Lakes,” loss of lake ice is stressing wildlife and affecting key recreational and economic opportunities.

Lake ecosystems are an influential part of Minnesota’s past, present, and future. Excavations of prehistoric sites reveal that people fished these waters over 11,000 years ago.² Ancient burial mounds, canoes, and pottery have also been discovered in the region.³  The Dakota and Anishinaabe Peoples have relied on the lakes for food and travel. The lakes also hold cultural importance for many Indigenous people in the region.

Minnesota's lakes support recreation opportunities and local economies. Boating and fishing contribute to Minnesota’s outdoor recreation industry, which contributed nearly $10 billion to the state economy in 2023.⁴ The state also boasts a strong roster of ice hockey teams and players—in fact, ice hockey is the official state sport.⁵ Frozen lakes provide free access for people of all ages to learn and play ice hockey together. Lake ecosystems also host a diverse array of plants and animals. Minnesota’s lakes provide habitat for fish, migratory waterfowl, and aquatic mammals like otters and beavers. Many of these animals rely on seasonal changes in lake temperature and winter ice cover—the very factors threatened by climate change.

Climate Impacts: Early Ice-Out Has Consequences for Safety, Economy, and Recreation

Minnesota has warmed more than 2.5°F since 1900, with most warming taking place over the winter.⁶ Warming affects the “ice-out” date for lakes, which is the date when lakes are mostly or completely free of ice.⁷ A long-term trend of earlier ice-out dates means a shorter season for winter recreation.⁶ Minnesota currently has about 12 fewer ice days than it did in 1970.⁸

Early ice-out and changing ice conditions can be dangerous. Milder winters with fewer days below freezing can reduce ice cover.⁹ For Minnesotans used to walking or driving on ice, intermittent freezing creates unexpectedly risky conditions that can lead to accidents. Thin or slushy ice can be unsafe for ice skating, ice fishing, hockey, and snowmobiling. Research shows that rising temperatures are likely linked to an increase in winter drownings during these activities.¹⁰

Less lake ice means fewer opportunities for people to participate in winter sports, which affects the state’s recreation economy. Events that depend on solid ice can be postponed or canceled if conditions are poor. For example, several tournaments, like the Brainerd Jaycees Ice Fishing Extravaganza, which contributes $1 million (in 2019 dollars) to the local economy in the Brainerd area, have been postponed or moved due to unstable ice.¹¹ Minnesota’s winter tourism and recreation industry could face additional challenges as lakes continue to warm.

Climate Impacts: Temperature and Precipitation Changes Can Negatively Impact Ecosystem Health

Climate change is disrupting lake ecosystems and local food systems. Minnesota’s lakes today have an average summer surface water temperature over 2°F higher than they did 50 years ago.¹² Precipitation has also increased, with two to three times as many heavy rain events per year since 2000 and more runoff into lakes and streams.⁶ Runoff that carries phosphorus and nitrogen, particularly from fertilizer and animal waste sources, can lead to eutrophication, a condition where a water body has exceptionally high nutrient levels.¹³ Eutrophication can lead to harmful algal blooms, hypoxia (low-oxygen conditions in water), and poor water quality, which can affect the numerous industries that depend on these water sources. In freshwater environments, harmful algal blooms can produce excessive amounts of biomass that clog boat motors and fish gills; contribute to hypoxia; or produce potent toxins that are hazardous to people, pets, and aquatic life.¹⁴

Changing conditions could impact trout and walleye, which are culturally important to Tribal Nations and important sources of revenue and recreation thanks to Minnesota fly-fishing.¹⁵ Coldwater fish such as cisco, an important food source for trout and walleye, rely on lakes that are cold, clear, and highly oxygenated. ^16, 17 Compounding changes resulting from increased runoff, biomass blocking out sunlight, larger hypoxic zones, and warmer water and air temperatures mean some species are losing their prime habitat or living under stressed conditions. Cisco habitat in Minnesota has dwindled in recent years from 650 to 176 lakes, putting stress on aquatic food chains, including commercially and culturally important species.^18,19

Wild rice, known as Manoomin or Psíŋ, holds particular importance for Minnesota’s Dakota and Ojibwe Tribes.²⁰ For hundreds of years, Indigenous people in the region have cultivated wild rice, which is an integral part of their diet and spiritual practices.²⁰ In addition to existing threats like habitat destruction due to development and sulfate pollution from industrial activities, climate change can further impact wild rice production.²¹ Changing precipitation patterns and warming winters disrupt growing conditions.²² Rice is sensitive to growing conditions like water depth, as it tends to need shallow water to grow.²³ Extreme precipitation events can also overwhelm plant roots. Minnesota is expected to experience more precipitation and increases in heavy rainfall events.⁶ Tribal communities are already feeling the environmental impacts on wild rice and reduced harvests, and there are ongoing efforts to take coordinated action to build resilience.^9,24 

Taking Action: Enhancing Habitat Conservation and Education

Addressing climate change requires reducing greenhouse gas emissions while preparing for and protecting against current and future climate impacts. Communities, public officials, and individuals in every part of the United States can continue to explore and implement climate adaptation and mitigation measures. In Minnesota, many public agencies, Tribes, and organizations are collaborating to protect vibrant ecosystems and the people that rely on them, including through:

• Conservation. A key step in adapting to climate change is conserving lake habitat by proactively restoring and preserving vulnerable lands. The Minnesota Department of Natural Resources is working with landowners to plant vegetation, which helps control eutrophication and support cisco populations.²⁵ Conservation easements, which are voluntary conservation agreements with landowners, are one way to keep land undisturbed and reduce runoff to lakes.
• Education and outreach. As lake ice becomes unreliable due to warmer winters, outreach can help increase awareness and reduce accidents. Tools such as Minnesota Sea Grant’s Ice-In and Ice-Out Widget can help the public understand how lake ice develops and changes with weather.²⁶ The Minnesota Department of Natural Resources also provides resources on ice safety to help those who enjoy fishing, skating, and hockey during the winter months.²⁷ 

To learn more about climate change impacts in Minnesota and the Midwest region, see Chapter 24 of the Fifth National Climate Assessment.

Related Resources

• EPA Climate Change Indicators: Lake Ice
• EPA Climate Change Indicators: Great Lakes Water Levels and Temperatures
• Harmful Algal Blooms in Water Bodies (EPA)
• Minnesota State Climate Summary 2022 (NOAA)
• Minnesota State Climatology Office (Minnesota Department of Natural Resources)

References

¹ Downing, J. A. (2021, May 17). Minnesota: Land of How Many Lakes? Minnesota Sea Grant. Retrieved September 22, 2023, from https://seagrant.umn.edu/news-info/directors-column/minnesota-land-how-many-lakes

² Minnesota Department of Natural Resources. (2010). History of fishing in Minnesota. In Fishing: Get in the Habitat! Leader’s Guide (2nd ed.). https://www.dnr.state.mn.us/minnaqua/leadersguide/lg_online.html

³ U.S. Forest Service. (n.d.). Prehistory. Superior National Forest. Retrieved September 26, 2023, from https://www.fs.usda.gov/detail/superior/learning/history-culture?cid=fsm91_049836

⁴ Office of Governor Tim Walz & Lt. Governor Peggy Flanagan. (2023, July 25). Governor Walz announces partnership to expand Minnesota’s $10 billion outdoor recreation industry. Retrieved September 22, 2023, from https://mn.gov/governor/newsroom/press-releases/?id=1055-586049

⁵ Office of the Minnesota Secretary of State Steve Simon. (n.d.). State sport - Ice hockey. Retrieved September 22, 2023, from https://www.sos.state.mn.us/about-minnesota/state-symbols/state-sport-ice-hockey/

⁶  Runkle, J., Kunkel, K. E., Frankson, R., Easterling, D. R., & Champion, S. M. (2022). Minnesota state climate summary 2022 (NOAA Technical Report NESDIS 150-MN). NOAA National Environmental Satellite, Data, and Information Service. https://statesummaries.ncics.org/chapter/mn/

⁷Minnesota Department of Natural Resources. (n.d.). 2023 lake ice out dates. Retrieved September 22, 2023, from https://www.dnr.state.mn.us/ice_out/index.html

⁸Our Minnesota Climate. (n.d.). Recreation, tourism threatened by winter warming. Retrieved September 22, 2023, from https://climate.state.mn.us/recreation-tourism-threatened-winter-warming

⁹ Wilson, A. B., Baker, J. M., Ainsworth, E. A., Andresen, J., Austin, J. A., Dukes, J. S., Gibbons, E., Hoppe, B. O., LeDee, O. E., Noel, J., Roop, H. A., Smith, S. A., Todey, D. P., Wolf, R., & Wood, J. D. (2023). Ch. 24. Midwest. In A. R. Crimmins, C. W. Avery, D. R. Easterling, K. E. Kunkel, B. C. Stewart, & T. K. Maycock (Eds.), Fifth National Climate Assessment. U.S. Global Change Research Program. https://doi.org/10.7930/NCA5.2023.CH24

¹⁰Sharma, S., Balgrave, K., Watson, S. R., O’Reilly, C. M., Batt, R., Magnuson, J. J., Clemens, T., Denfeld, B. A., Flaim, G., Grinberga, L., Hori, Y., Laas, A., Knoll, L. B., Straile, D., Takamura, N., & Weyhenmeyer, G. A. (2020). Increased winter drownings in ice-covered regions with warmer winters. PLOS ONE, 15(11), e0241222. https://doi.org/10.1371/journal.pone.0241222

¹¹Knoll, L. B., Sharma, S., Denfeld, B. A., Flaim, G., Hori, Y., Magnuson, J. J., Straile, D., & Weyhenmeyer, G. A. (2019). Consequences of lake and river ice loss on cultural ecosystem services. Limnology and Oceanography Letters, 4(5), 119–131. https://doi.org/10.1002/lol2.10116

¹² GLISA. (n.d.). Climate change in the Great Lakes Region references. Retrieved June 21, 2024, from https://glisa.umich.edu/climate-change-in-the-great-lakes-region-references/

¹³NOAA National Ocean Service. (2024). What is eutrophication? Ocean Facts. Retrieved September 22, 2023, from https://oceanservice.noaa.gov/facts/eutrophication.html

¹⁴NOAA. (2016). What is a harmful algal bloom? News & Features. Retrieved September 26, 2023, from https://www.noaa.gov/what-is-harmful-algal-bloom

¹⁵Minnesota Department of Natural Resources. (n.d.). Impacts of climate change. Climate Change and Minnesota. Retrieved June 21, 2024, from https://www.dnr.state.mn.us/climate/climate_change_info/impacts-climate-change.html

¹⁶Jacobson, P. C., Cross, T. K., Zandlo, J., Carlson, B. N., & Pereira, D. P. (2012). The effects of climate change and eutrophication on cisco Coregonus artedi abundance in Minnesota lakes. Advances in Limnology, 63, 417–427. https://doi.org/10.1127/advlim/63/2012/417

¹⁷Hansen, G. J. A., Wehrly, K. E., Vitense, K., Walsh, J. R., & Jacobson, P. C. (2022). Quantifying the resilience of coldwater lake habitat to climate and land use change to prioritize watershed conservation. Ecosphere, 13(7), e4172. https://doi.org/10.1002/ecs2.4172

¹⁸Van Zuiden, T. M., Chen, M. M., Stefanoff, S., Lopez, L., & Sharma, S. (2016). Projected impacts of climate change on three freshwater fishes and potential novel competitive interactions. Diversity and Distributions, 22(5), 603–614. https://doi.org/10.1111/ddi.12422

¹⁹Renik, K. M., Jennings, M. J., Kampa, J. M., Lyons, J., Parks, T. P., & Sass, G. G. (2020). Status and distribution of Cisco (Coregonus artedi) and Lake Whitefish (Coregonus clupeaformis) in inland lakes of Wisconsin. Northeastern Naturalist, 27(3), 469–484. https://doi.org/10.1656/045.027.0307

²⁰Bouayad, A. (2020). Wild rice protectors: An Ojibwe odyssey. Environmental Law Review, 22(1), 25–42. https://doi.org/10.1177/1461452920912909

²¹Minnesota Pollution Control Agency. (2024). Protecting wild rice waters. Water Quality Initiatives. Retrieved February 22, 2024, from https://www.pca.state.mn.us/air-water-land-climate/protecting-wild-rice-waters

²² Hosterman, H., Ritter, K., Schuldt, N., Vogt, D., Erickson, D., Griot, O., Johnston, E., Schmidt, K., Ravindran, E., LaBine, R., Chapman, Sr., E., Graveen, W., Peroff, D., Taitano Camacho, J., Dance, S., Krumwiede, B., & Stirratt, H. (2023). Lake Superior Manoomin cultural and ecosystem characterization study. Ecology and Society, 28(3), art17. https://doi.org/10.5751/ES-13763-280317

²³Minnesota Department of Natural Resources. (n.d.). Wild rice management. Shallow Lakes Program. Retrieved February 22, 2024, from https://www.dnr.state.mn.us/wildlife/shallowlakes/wildrice.html

²⁴Harrelson, C. (2023). Indigenous-led monitoring protects wild rice in Great Lakes region. U.S. National Science Foundation. Retrieved June 21, 2024, from https://new.nsf.gov/science-matters/indigenous-led-monitoring-protects-wild-rice-great

²⁵Minnesota Department of Natural Resources. (n.d.). What DNR is doing. Climate Change and Minnesota. Retrieved September 22, 2023, from https://www.dnr.state.mn.us/climate/climate_change_info/what-dnr-doing.html

²⁶ Minnesota Sea Grant. (2024). Minnesota lake ice-in and ice-out widget. University of Minnesota Duluth. Retrieved September 22, 2023, from https://seagrant.umn.edu/programs/recreation-and-water-safety-program/mn-ice-ice-out

²⁷Minnesota Department of Natural Resources. (n.d.). Ice safety. Retrieved September 22, 2023, from https://www.dnr.state.mn.us/safety/ice/index.html