How climate change impacts our water

Originally posted on November 11, 2016


The following is a guest commentary submitted by Jennifer McKay, policy specialist for the Tip of the Mitt Watershed Council.

For many part-time residents, summers in Northern Michigan represent a reprieve from the sweltering days experienced in other parts of the country. Year-round residents look forward to pleasantly warm summer days punctuated by cool nights and misty mornings on the water. This past summer was perfect for water recreation lovers, with some days in the 90s and an unrelenting sun overhead. In fact, summer 2016 was abnormally hot across the globe, including here in Northern Michigan. According to the National Oceanic and Atmospheric Administration (NOAA), July 2016 was 1.57° F above the 20th-century average and was the hottest July in recorded history.

With so much of Northern Michigan’s economy based in outdoor activities, the hot and clear weather was a boom for many local businesses. Campgrounds, outfitters, restaurants, and retailers were among those reporting increased traffic. While hot summer weather may benefit our local economy, it also has an impact on water resources.

 At the most basic level, higher air temperatures and more sunlight mean warmer water. According to the Great Lakes Environmental Research Lab, the average surface temperature of Lake Michigan peaked at 75.6° F on Aug. 18. This was 6.2° F warmer than the long-term average for that date. Many of our inland lakes reached the upper 70s and low 80s during late summer. Data from our Volunteer Lake Monitoring Program show warmest surface water temperatures this summer were on Walloon Lake and Thayer Lake, with readings topped out at 82.4° F.

What did this mean for water quality and the life within and around our lakes? For one, warmer water promotes biologic activity, meaning that plants and algae grow better in warmer waters. The Watershed Council received many reports of purple loosestrife, Eurasian watermilfoil, Phragmites, and other aquatic invasive plant species growing more heavily than normal this past summer. While these invasives can inhibit recreation and lakefront views, more damaging are the ecological impacts. One of these impacts includes monoculture growth, resulting in decreased biodiversity and less food for waterfowl and gamefish.

One curiosity of warmer weather is the appearance of a freshwater jellyfish. “Blooms” of these freshwater jellies coincide with heat waves and this summer, the Watershed Council received reports from boaters and swimmers who found the jellyfish in Crooked and Burt Lakes. Despite the sightings, there is no need to worry. While the tentacles have the ability to sting, they are far too small to be felt by humans.

These warmer air and water temperatures are just one of many effects of climate change already apparent in the Great Lakes region. We have seen a number of observable changes in temperature, precipitation, and extreme weather events over the last century, including:

— Average temperatures in the Great Lakes region increased 2.3 degrees Fahrenheit between 1968 and 2002

— Average annual ice coverage on the Great Lakes declined 72 percent between 1973 and 2010

— Total precipitation has increased 11 percent since 1900 in the eight Great Lakes States

— From 1975 to 2004, the annual number of days with land snow cover decreased by 15 and the average snow depth decreased by 2 inches, and

— The frost-free season lengthened by 9 days in the Midwestern U.S. between 1958 and 2012

 These trends are expected to continue along with changes in the frequency of intense storms, extended droughts, and heat waves. These changes to regional climate pose increased risks to our water resources, built environment and infrastructure, ecosystems, and recreation and tourism sectors.

As a result, many Great Lakes states, communities, organizations, and individuals are taking steps to manage or adapt to climate change impacts to protect coastal communities. These can be technologies, procedures, practices, and behaviors taken in anticipation of impacts or in response to impacts.

They are practical steps to help avoid or reduce climate change consequences and protect communities from the likely disruption and damage that will result from effects of climate change.

In an effort to help you protect our coastal assets, we developed a publication, Climate Change Adaptation: A Toolkit of Best Management Practices for Coastal Wetlands in Michigan.

The Toolkit provides information about climate change adaptation best management practices that can be implemented on an individual, local, or regional level to address many of the potential impacts of climate change. It can be used by almost anyone in Michigan, including homeowners, developers, municipalities, organizations, and water and wetland resource managers. We encourage you to use the publication to help ensure the health of our Great Lakes and coastal communities in the future as climate changes continue to impact our region.

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