Changing Grounds
Monitoring carbon (and trying to anticipate the future) in the Hudson Bay Lowlands
Monitoring carbon (and trying to anticipate the future) in the Hudson Bay Lowlands
Our Twin Otter aircraft circled, descending gradually with each pass until the pilot was able to settle the spongy oversized tires onto an uneven gravel strip in Ontario’s Polar Bear Provincial Park. The abandoned runway, which is slowly being reclaimed by shrubs, is all that remains of a former Cold War-era radar installation about 1,000 kilometres northeast of Winnipeg near the southern shores of Hudson Bay.
With the propellers stopped and secured, my team from the Ontario Ministry of the Environment and Climate Change worked quickly to transfer the plane’s payload — the construction gear, materials and components to build a carbon-monitoring station — into heavy rope nets, which were then lifted by helicopter to the installation site a few kilometres away. This would be our temporary base of operations, a rare patch of stable dry ground in an otherwise soggy and undeveloped landscape, for the next two weeks. It was September 2017, and we were there to construct the second of two carbon-monitoring stations. We built boardwalks, erected solar panels and a metal tower, and set up and connected an array of high-tech sensors wired to a data-logging computer.
All the while, we had to remain on alert for polar bears, which are forced ashore for several months each year when the sea ice melts on Hudson Bay. Even though we were 30 kilometres inland, bears had been spotted in the area, and we were mindful of a potential encounter. Thankfully, our only visitors were curious caribou.
This carbon-monitoring station in Polar Bear Provincial Park, along with a nearby station we had erected exactly one year earlier, is now beaming data by satellite to Ministry of the Environment and Climate Change offices 1,300 kilometres to the south in Toronto. Together, they are the newest in the province of Ontario’s network of five stations stretching south to north along a climate and permafrost gradient from Moosonee to Peawanuck. The stations measure the exchange of greenhouse gases (carbon dioxide and methane) between the land and the atmosphere in the Hudson Bay Lowlands, a globally significant carbon store.
The Hudson Bay Lowlands surround the western side of Hudson Bay and James Bay, spanning across northern Ontario and extending into Manitoba and Quebec. With an area of 325,000 square kilometres, these lowlands cover roughly 3.5 per cent of the surface area of Canada. Ontario’s Far North Science Advisory Panel has described the region as “one of the world’s largest, most intact ecological systems.” The region is a biodiversity stronghold, home to mammals such as caribou, Canada lynx, martens, grey wolves, wolverines and the southernmost population of polar bears in the world. The region is also of global importance for migratory birds. It is a unique and special place.
The second largest peatland in the world covers the flat and poorly drained landscape of the Lowlands, and because of the cooling influence of Hudson Bay and James Bay and the persistence of sea ice, the climate is cold for its latitude. The region contains the southernmost extent of non-alpine permafrost in North America. These cold and wet conditions slow soil decomposition, allowing organic matter to accumulate over thousands of years. They have created a massive store of carbon.
Over the past few decades, however, the region has experienced a warming trend, the implications of which are uncertain. Certainly, more change is coming. Climate models predict considerably shorter ice-cover seasons on Hudson Bay and James Bay leading to warmer and longer summers and warmer and shorter winters. Warming could result in the drying of the peatlands, melting of the permafrost and release of carbon to the atmosphere, creating a positive feedback loop with potential implications for the global climate. Drying is also likely to increase wildfires, burning of peat and loss of carbon to the atmosphere.
Sam Hunter, an environmental steward with the Mushkegowuk Council, has been keeping watch on a weather station installed on a permafrost palsa (an oval-shaped raised mound of frozen peat) near his home in Peawanuck. The station has been slowly keeling over as its frozen foundation melts and slumps. “Most people think that polar bears are the indicators of climate change,” Hunter says. “For me, it’s the palsas.”
Hunter joined my team in installing our monitoring stations in Polar Bear Provincial Park. He explained to me how the melting of permafrost is making it more challenging to move around on the landscape. He also showed me how the fragrant leaves and stems of the dwarf Labrador-tea plant, found only on the permafrost palsas, can be used to brew a better tea than the taller variety of the plant.
Our two stations in the park are only one kilometre apart, but they are monitoring very different landscapes. The first is installed on a peat plateau, over intact permafrost that remains frozen at 30-40 centimetres below the surface in the heat of summer. The second is in an area where palsas have melted and collapsed, creating a patchwork of shallow oval-shaped ponds. Findings from these two monitoring stations will provide insights into what happens to the carbon that is stored in frozen peat when permafrost melts, helping to fill a key gap in the science of northern peatlands.
“Most people think that polar bears are the indicators of climate change. It’s the palsas”
Elyn Humphreys, a peatlands researcher at Carleton University in Ottawa, has analyzed the data collected since 2010 at Ontario’s two carbon monitoring stations near the Victor diamond mine, west of Attawapiskat, and our third station west of Moosonee. Humphreys’ calculations reveal a delicate balance between carbon uptake and loss, a balance that is sensitive to changes in temperature and other weather conditions. Her findings show that the monitored peatlands continue to accumulate carbon despite recent warming trends, taking up between 49 and 82 grams of carbon per square metre each year from the atmosphere.
Northern peatlands are important to the global climate system not only because they are massive carbon stores but also because when warming they release methane into the atmosphere. Methane is a much more potent greenhouse gas than carbon dioxide. Humphreys’ calculations show that the amount of methane released by the monitored peatlands currently is less than 10 per cent of the amount of carbon taken up as carbon dioxide. These findings are especially important because ecosystem-scale measurements of methane emissions from northern peatlands are lacking worldwide. Results from Ontario’s carbon monitoring stations are shared on the online Ameriflux network with researchers around the world.
The Omushkegowuk people have called the Hudson Bay Lowlands home for thousands of years. Comprising several Cree First Nations, their communities are remote, linked only by air, water and winter roads. They rely on the land for their food, medicine, livelihoods and culture.
In January 2018, the Mushkegowuk Council hosted a climate summit in Timmins, Ont., where Elders, youth, community members and environmental managers and scientists met to share knowledge and identify gaps in our understanding of how to protect the traditional lands and the future well-being of the Omushkegowuk people. My colleague Chris Charron, an air monitoring manager at the Ontario Ministry of the Environment and Climate Change, attended. “It was a fascinating and somewhat sobering two days,” he told me. “For those of us who live in the south, it moved the conversation from one that has been primarily academic in nature, to one that is full of real-world consequences. Elders from several different communities spoke of the changes they are witnessing to the land, to the water and to wildlife. Many felt that the Earth was sick.”
The climate summit reinforced the importance of our efforts to better understand the role of the Hudson Bay Lowlands in the global climate system and how climate change could affect these globally significant peatlands. It also highlighted the fact that climate change is a real and present concern and that strategies to adapt to a changing world are needed, particularly in the Hudson Bay Lowlands where the effects of climate change are already being felt.
Thanks to the carbon-monitoring stations erected, and the work of researchers and scientists throughout the North along with committed local residents, we are getting a clearer picture of the kinds of changes occurring and what we can do in the coming years to address them.1
Aaron Todd works in the monitoring and reporting branch of the Ontario Ministry of the Environment and Climate Change