![Chart of wave heights [Great Lakes Observing System]](https://npr.brightspotcdn.com/dims4/default/0865f85/2147483647/strip/true/crop/1798x922+0+0/resize/840x430!/format/webp/quality/90/?url=http%3A%2F%2Fnpr-brightspot.s3.amazonaws.com%2Flegacy%2Fuploads%2F2017%2F10%2F30%2Fwave.png)
By Dave Rosenthal
For anyone who doubts the power of the Great Lakes, now's the time for a reset.
This week, data buoys on Lake Superior recorded 28.8-foot waves, according to the Great Lakes Observing System.
The monster waves were recorded Tuesday morning by the Granite Island and Munising, Mich., data buoys as a storm system moved along Michigan's Upper Peninsula. Wind gusts at the time measured above 70 mph.
GLOS, part of the National Oceanic and Atmospheric Administration, gathers data from buoys and other sources. It offers the data to researchers and the public.
“Events like these illustrate the importance of having a robust observing system in place,” Kelli Paige, executive director of GLOS, said in a statement issued Thursday. “It’s also worth noting that these buoys will need to be taken out of the water within a month or so, additional resources could help us establish a cabled observation system allowing this sort of data gathering year-round.”
Records from the National Data Buoy Center date back to 1979, when the first buoys were placed in the Great Lakes to aid freighters. Since then, the network of buoys has expanded.
Data buoys measure wave heights over a 10-minute period and then report the average of the largest third of the waves. That's the standard practice for buoys, says project engineer Ed Verhamme of LimnoTech, which operates and maintains Great Lakes buoys.