Lake ice ties age-old traditions to land during cold months in Canada, creating a cultural roadmap for recreation that utilizes the country’s frozen lakes. In all, there are more than 30,000 lakes in Canada. First Nations, the indigenous peoples of Canada who lived below the Arctic Circle, knew the value of these lakes more than anyone.
Lake ice records, kept over hundreds of years by First Nations, support long-held evidence that frozen lakes were a causeway for travel and trade between communities.
By keeping track of the seasonal thaw and freeze, indigenous groups could predict when it was safe to use frozen lakes as passage to local islands. But what they didn’t predict was climate change.
With water temperatures rising at a rapid pace, Canada’s lake ice is becoming more infrequent, or disappearing altogether during winter seasons. Not only will this upset the ecological balance of Canada’s various fresh water sources, it will take regional traditions with it, too.
But there is more at risk from disappearing lake ice than recreation, explains scientist Paul M. Cooley, Ph.D., founder and president of NextGen Environmental Research Inc. in Winnipeg, Canada. The presence of seasonal ice acts as a canary in a coal mine for monitoring the onset of climate change. As populations grow, so do the risks for people who use the waterways. “This is a new environment for everyone,” Cooley explains. “So even for people who are familiar with lake ice, we don’t have a history of the changes that are expected to come due to climate warming.”
This year, Cooley and the NextGen team will unveil the world’s first RADAR satellite based Lake Ice Hazard Advisory Service, packaged in a mobile app called “Ice Time.”
Over three winters and 84 lakes, the NextGen team utilized a mix of onsite data, unmanned aerial vehicle (UAV) photogrammetric images and synthetic aperture radar (SAR) satellite data to measure ice cover. Funded by the Canadian Space Agency, NextGen’s research will help provide regional residents and recreational visitors safe passage through the lake ice and help manage the onset of climate change.
Surveying In Dangerous Conditions
Paul M. Cooley, Ph.D., isn’t a professional surveyor, per se. “I’m actually a scientist,” he clarifies. “I’ve done a lot of surveying to support science. It’s something I’ve learned along the way as opposed to something that I had dedicated study towards. But my surveying is always in support of the science.”
To map Canada’s regional lake ice, the use of a drone — or an unmanned aerial vehicle (UAV) — was an essential survey tool, says Cooley. While the NextGen team was safe on solid ground, a UAV collected photogrammetric images of lake ice from above, over areas too hazardous to survey by foot.
Considering the region’s rough winter air, NextGen chose senseFly’s eBee Plus for the job, a medium-sized, fixed-wing mapping drone that can map wider areas and is more aerodynamic when compared to copter drones.
In May 2019, the American Petroleum Institute (API) published a “Guide for Developing a UAS Program in the Oil and Natural Gas Industry.” With safety as its number one priority, the organization continues to study how drones can be integrated into very complex processes and how they might be used for inspections. It can take years to write new standards, but with increasing pressure to cut costs as oil prices fall, drones are getting more attention as a cost effective way to safely maintain industrial facilities.
During bathymetric surveys, drones also prove to be a cost effective way to access water and underwater data.
Not to be confused with hydrography, “bathymetry” refers to the ocean’s depth relative to sea level. However, over the years, bathymetry is widely used to refer to any type of underwater topographic survey, including rivers, streams and lakes. In some cases, dense seaweed can prevent the lowering of echo sounders in water, or complicated water access can rule out unmanned surface vehicles (USVs) entirely. In other cases, you may need to conduct multiple surveys of small ponds, lakes or trenches. For such survey projects, drones can be outfitted with an echo sounder to move across a water’s surface.
“It is better to use a drone with an echo sounder for mapping, measuring and inspecting tasks and environmental monitoring if you are conducting bathymetric surveys of tailings dams and ponds,” explains Alexey Dobrovolskiy, CTO at SPH Engineering, which provides software and integration services for unmanned systems. “Drones are also used in bathymetric surveys of ponds in open pits, mapping of sediments of oxidation and tailing ponds, and mapping water depths and sediments before dredging and cleaning of ponds, lakes, rivers, and canals.”
Whether surveying above or below ice, Dobrovolskiy explains that the most important thing to know is the types of data files that will be needed to provide survey results. Depending on the technology needed for the job, drone models typically can adjust.
“For (bathymetric) operations, we recommend using standard commercially available drones like DJI M600 Pro, M210 or the new M300,” says Dobrovolskiy. “You can also use drones based on the open source Pixhawk autopilot. If you choose to use standard popular drones, the echo sounder will be just one more sensor for your multi-purpose bird. You can use it for photogrammetry, LIDAR, magnetometer and other missions.”
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