April 23, 2021 – There is a sign at Sleeping Bear Dunes National Lakeshore warning visitors that if they go down the 450-foot sand dune to Lake Michigan and cannot get back up on their own, there will be a fee to be rescued. As of 2019, the fee was $3000. With swimming, hiking, biking, and dune climbing galore at the national park site, only bears take time to sleep!
It’s one of the most dramatic sights in the Midwest because it is so unexpected. One expects to see tall sand dunes in deserts and along ocean coastline but not next to a lake.
The park includes 65 miles of lakeshore in northern Michigan along Lake Michigan, one of the five Great Lakes and to many who reside in western Michigan, the greatest of the Great Lakes.
Visitors can take a step back in time and visit a small museum located on the shore. From the early 1920s to the early 1940s, tart cherries were canned there and then shipped around the world. Even today, this area produces about 70 percent of the tart cherry crop in the United States.
Today the cannery is a museum. One interesting artifact there is a beacon used in a lighthouse. The DCG-36 (Directional Code Beacon) was developed for airports during World War II but quickly began being used in lighthouses to guide ships. In 1980, new automated lights were installed.
Watching a sunset during any season from the top of a sand dune is a breathtaking experience. It’s easy to access by car so a trek up hundreds of feet of sand is not required.
According to the National Park Service (NPS), the dunes are as old as the continental ice sheets. During an Ice Age in prehistoric times, very thick ice covered most of Canada and the northern portions of Midwest and Northeast in the United States. When temperatures warmed and the ice melted, the movement of the glaciers formed the topography of the area. Massive sand dunes formed.
Moraines are an aggregate of material left from fast moving glaciers as ice melted. Trying to imagine massive ice sheets moving over an entire continent is almost impossible. Many national parks have evidence of these melting glaciers in rock formations and lakes that formed.
There are also sand dunes in southwestern Michigan along Lake Michigan but the dunes are not as high as the Sleeping Bear Dunes.
One other national park site in the Great Plains/Midwest region has massive sand dunes. In southern Colorado, Great Sand Dunes National Park and Preserve has the tallest sand dunes in North America with one dune 742 feet above its base.
At Sleeping Bear Dunes, there is a campground so a few humans do sleep there when it’s warm but need to be careful not to attract the bears!
Sand – main ingredient in glass
Sand is the main ingredient in glass. Sand is present in glass as silicon dioxide – SiO2. One legend about glass is that it was first formed when lightning struck sand and the very high temperatures turned the sand to glass.
Today, glass is made by heating a molten sand mixture in a glass furnance to very high temperatures – 2,150 degrees Fahrenheit. Studio glass is made by shaping the sand mixture (the “gob”) when it is between 1,500 – 1,600 degrees. Items from practical containers to artistic sculptures can be made. Colored glass is made by adding chemical elements, such as cobalt and copper, to the glass as it is being formed.
Dale Chihuly is a famous glass artist. His glass museum in Seattle near the famous Space Needle is beautiful.
REVIEW QUESTIONS
1. Where is Sleeping Bear Dunes National Lakeshore?
2. When was it established and protected as a national park site?
3. How were the sand dunes formed?
4. How tall is the sand dune for which the park has a fee to be rescued from the bottom of it?
5. What is the main ingredient in glass?
INQUIRY QUESTIONS
1. What do Sleeping Bear Dunes and Great Sand Dunes National Park and Preserve have in common?
2. How is glass made? At what temperature range is glass formed?
3. Do you think the legend about glass is possible?