As part of Lakes Appreciation Month, MI Environment today features an article from the State of the Great Lakes report by Hans W. Van Sumeren, director of the Great Lakes Water Studies Institute at Northwestern Michigan College.
There is a need for better mapping of the Great Lakes and all the world's large lakes. In fact, there is significantly more information at a much higher resolution of the surface of Mars than there is for either the Great Lakes or the world's oceans. Estimates of high-resolution bathymetry and substrate data for the Great Lakes basin vary from 4-12 percent, lagging behind the 20 percent coverage of the world's oceans. With advances in technology and the need for a better understanding of the Great Lakes, we are now at a key juncture to develop partnerships and raise the funding needed to launch Lakebed 2030, a full mapping of all the Great Lakes.
Why it's important
Large gaps in lakebed mapping indicate a need for data collection strategies. New collaborative approaches combined with accessible data repositories and technological advancements can help move researchers closer to a well understood Great Lakes basin and may allow for one day realizing a complete and comprehensive view of the basin's lakebed. A Lakebed 2030 initiative would drive support and the development of strategies for obtaining 100 percent coverage of the Great Lakes bottomlands.
Great Lakes initiative
Partnering with the Marine Technology Society and the Great Lakes Observing System, Northwestern Michigan College in Traverse City has hosted several TechSurge Lakebed 2030 conferences to discuss the initiative. A successful Lakebed 2030 project will produce a definitive map of the Great Lakes, empower policy decision-making, encourage sustainable use of the lakes and foster scientific research that relies on comprehensive information on the Great Lakes. Funding mechanisms could include promoting public/private partnerships, attracting new investments, aligning priorities with the philanthropic sector priorities and crowdfunding.
The bigger picture
The vision for Lakebed 2030 is to develop a comprehensive map for a sustainable and healthy Great Lakes, foster new joint research collaboration and cooperation within the Great Lakes basin and prioritize critical Great Lakes mapping needs. It also could synthesize past, current and future mapping efforts to define trends, knowledge gaps and priorities for future research.
What needs to be done
Fulfilling this vision requires building capacity at local, regional and international scales and further developing (or creating) collaborations that share collected data, technological advances and workflow strategies. The information must be freely accessible in a digital repository so gaps in data coverage can be assessed and prioritized through continuing collaborations.
Advancements in technology
Autonomous survey platforms will be integral to a Lakebed 2030 initiative. Rapid advances in acoustic technology and robotics are leading to innovative approaches that maximize efficiency, resolution and visualization. Multibeam sonar data can provide a broad understanding of the lakebed bathymetry, substrate and water column in a single pass. Unmanned surface vessels, autonomous underwater vehicles and long range sub-surface gliders now navigate all marine domains equipped with a wide variety of sensor packages. The use of these platforms extends data collection windows and requires significantly fewer personnel for operation. Further developments in unmanned aerial systems can capture nearshore environments at a much lower cost and faster response.
How it works
The bathymetric mapping systems used today can collect data across multiple frequencies at swath widths of more than three times the water depth. This use of multiple frequencies provides multispectral backscatter return from the lakebed, with each return providing significant delineation in habitat classification and general lakebed structure. Staggering those frequencies during a single collection pass ensures comparability of the backscatter across all frequencies thus providing the user multiple perspectives of the lakebed in a single transect.
Mapping the Straits
Recent mapping in the Straits of Mackinac by the National Oceanic and Atmospheric Administration (NOAA) included the use of multiple autonomous surface vessels coupled virtually to a survey vessel, which allowed for a near doubling of the swath of mapping coverage without requiring additional personnel or time on task. Massive amounts of data being collected include multiple depths at decimeter resolution and highly accurate positions, identification of lakebed features, significant substrate identification and complete water column coverage. Advancements such as this have revolutionized the ability to comprehensively visualize the lakebed and water column.
Realizing a comprehensive map of the Great Lakes will require significant contributions from beyond the formal mapping and science channels. Integrating commercial off-the-shelf mapping technologies into crowdsourcing opportunities represents an additional approach toward reducing the gaps in data coverage and accelerating the vision of Lakebed 2030. Off-the-shelf technologies are improving in quality and accessibility and could be used to outfit ferries, commercial ships and recreational vessels to collect data during their normal operations.
Photo caption: A Kongsberg Mesotech Ltd. maritime autonomous underwater vehicle, with multibeam sonar, used to map bottomlands. Photo credit: Kongsberg Mesotech Ltd.