High Frequency Radar to be installed in Straits of Mackinac
The combined data from the existing buoy, the HF radar data will provide a improved picture of currents in the Straits of Mackinac.
Those seeking to monitor currents in the Straits of Mackinac will soon have high quality data at their fingertips thanks to one of GLOS’ latest projects. By securing an NOAA grant, GLOS is funding the purchase of a high frequency radar system that will give detailed information on water currents through the narrow straits.
The implementation of the plan is being carried out by two researchers at Michigan Technological University, Lorelle and Guy Meadows. The technology has long been in use along U.S. coasts and was thought to be only viable in ocean settings. Lorelle, however, first demonstrated its effectiveness in Lake Michigan in 1999-2001 with a specially built system and again in 2011 at Point Betsie with a commercial CODAR SeaSonde system at distances of 10-15 miles, which, Guy noted, is a perfect distance for many Great Lakes applications. This new monitoring system will lend itself to a plethora of applications from tracing any potential surface contaminant threat to monitoring ships and ice flows in the straits.
Actually a form of radio wave, HF radar systems collect information by bouncing the transmitted waves off of a moving surface and measuring the time the waves take to reflect back to a receiver unit. Guy explained that this time that the waves take to reflect is known as a “Doppler shift,” and is similar to a police officer’s radar gun measuring the speed of an approaching car.
Guy says that aside from the single Michigan Tech buoy located just to the west of the Mackinac Bridge, there is currently no viable way to monitor real-time currents in the straits. Used in tandem with the new radar systems, Meadows says we will have a significantly improved picture of what’s going on in this crucial waterway. The radar system will create a new image every 20 minutes detailing the vector directions of currents across the surface and will display this data on the GLOS portal.
There is one problem: the bridge. While one pair of radar is good, two pairs would give a much fuller picture, overcoming the bridge’s interference. “We’d like to move the bridge,” Meadows joked. Both Meadows are currently in talks to secure funding for a second pair of CODAR SeaSondes that could be positioned on the east side of the bridge looking toward Mackinac Island.
Live data is expected to be available on the portal in 2020.
Researchers are working with CODAR, the radar manufacturer, to settle on placement of the radar like the two pictured below.