Sensors on Yellowknife lakes could be start of larger ice network
Sensors monitoring two lakes near Yellowknife could help northerners stay safe on the ice as the climate changes, researchers say.
On Ryan Lake and Landing Lake, sensors known as snow and ice mass balance apparatuses – or Simba, for short – have been in place since the ice was thick enough to walk on this winter. They measure ice thickness and snow depth every 15 minutes.
The sensors’ use was first reported by NNSL.
Arash Rafat, a master’s student at Wilfrid Laurier University, told Cabin Radio the team hopes to assess how those conditions change over a season. Testing will run for four to five months.
Rafat said Landing Lake was chosen because it shares characteristics with other lakes in the region – being just two to three metres deep – and there is a weather station at the site. Ryan Lake was selected because it is unique for the area, extending to a depth of around 90 metres.
“It’d be really interesting, we thought, to see what a deep lake might look like versus a shallow lake, because how the ice forms and reacts to the climate is very different between a deep lake versus a shallow lake,” Rafat said.
Ice on shallow lakes is thinner, Rafat explained, because the water stays warmer. Rapid changes in air temperature – which the NWT has seen this winter – also affect ice temperatures, he said, especially where snow cover is thinner.
Some water bodies in the NWT have experienced changes in depth in recent years. The territory saw historically high water levels on some rivers, streams and lakes over the past two summers.
Rafat said when water levels are low and air temperatures are cool in the NWT, the ice that forms on lakes is clear – what’s known as black ice. With high water levels and deep snow, he said, a layer of white ice can form, which is weaker and less transparent. That affects how thick lake ice becomes over time and when it melts.
Homa Kheyrollah Pour, the university’s assistant professor of geography and environmental studies, who is leading the research, said in the future, more white ice could form on lakes in the region due to temperature fluctuation and climate change.
“That’s a concern,” she said.
Rafat said he became interested in the project as it uses science to help communities.
“I thought it’d be a unique way of approaching a problem that exists and that hasn’t really been tackled before, and that has tangible benefits,” he said. “To me, that was really important.”
Rafat said the long-term goal is to set up a network of sensors across the North. The team has purchased two more Simba devices and plans to discuss with the NWT government where they should be placed.
Kheyrollah Pour said the sensor data can be combined with other data on how lakes are changing over time, taken from space, to inform decisions about ice safety.
Ice safety is a concern for northern communities as the climate changes.
After a resident fell through Grace Lake’s ice up to their chest, the City of Yellowknife reminded residents that areas of weakness can exist, even when the ice on a lake is generally considered thick enough to walk on.
Tara Tompkins, the resident in question, said she fell in after walking to the lake on her lunch break to get some fresh air.
She was able to haul herself out of the water, but worries for others similarly caught by surprise.
“I’ve been there before,” she said of the area. “I’ve walked there, skied there, I’ve gone down this path. I thought it still would be solid but that’s an area of weakness.”
Tompkins said the incident made her think about being better prepared for emergencies when walking or skiing on the ice, like carrying dry clothing or travelling in a group.