An expert panel has released its report assessing the extent to which nature-based climate solutions can help Canada meet its greenhouse gas (GHG) emission reduction targets.

The expert panel includes Dr. Sue Ziegler, a professor in the Department of Earth Sciences, Faculty of Science, at Memorial.

The report comes on the heels of the most recent United Nations Framework Convention on Climate Change (COP27) and just ahead of the United Nations Biodiversity Conference (COP15) in Montreal, Que., which aims to develop actions to end biodiversity loss.

“The connection between these two crises, biodiversity and climate, is fundamental, or better yet elemental — think carbon — to urgent global efforts to mitigate rapid climate change,” said Dr. Ziegler.

Restoring, protecting or expanding ecosystems

Nature-based climate solutions (NBCSs) are practices aimed at restoring, protecting or expanding ecosystems that sequester GHGs, e.g. carbon sinks within wetlands and forests, or which reduce the release of GHGs into the atmosphere, such as avoiding deforestation and nutrient management in agriculture.

Environment and Climate Change Canada (ECCC) and five other supporting federal departments asked the Council of Canadian Academies (CCA) to establish an expert panel to complete the report.

It concludes protecting and enhancing the vast carbon stores in Canada’s natural ecosystems could put a small but significant dent in Canada’s emissions, but an aggressive commitment to reducing human-caused emissions remains critically important.

The panel noted preserving the vast ecosystems of Canada, and their carbon stores, is imperative to successful climate action, as development and land-use changes, as well as increasing temperatures, make them vulnerable to disturbance and risk the release of more GHGs into the atmosphere.

Joining the panel and research process in February 2021, Dr. Ziegler contributed her expertise in climate responses and feedbacks across boreal terrestrial and aquatic ecosystems.

Her research group has published recent research informing understanding of key soil carbon storage controls and how climate change modifies important carbon-feedbacks within the boreal landscapes of our region, including terrestrial to aquatic and coastal marine processes.

“Canada has globally significant, vast stores of carbon, but all these stores are actively linked to climate in ways that can enhance the uptake of carbon dioxide from the atmosphere or release more,” said Dr. Ziegler.

“The natural ecosystems of Canada are doing a lot of good already with respect to our emissions, and we need to pay very close attention to that. I really hope this report stimulates a lot of interest and investment in further protecting and understanding the ecosystems that have already been reducing the impact of our emissions but are at real risk given rapid climate change.”

A global challenge

The report determines full implementation of NBCSs would mitigate a small fraction of Canada’s current annual emissions, even with aggressive support and deployment.

Although modest, they can also bring about other important benefits, including coastal flood control, improved air and water quality, reduced soil erosion, enhanced property values, reduced urban heat-island effects, and greater biodiversity.

“Canada has the opportunity to become a leader in nature-based climate solutions and it’s our hope that this report will help to inform both Canadian and international efforts to meet the global challenges of climate change,” said Dr. Glen MacDonald, chair of the expert panel.

Barriers and benefits

The Government of Canada has committed to reducing GHG emissions to at least 40 per cent below 2005 levels by 2030 and achieving a net-zero Canadian economy by 2050.

The panel says NBCSs can provide a way to protect, restore and manage ecosystems that sequester carbon and help the government to meet its climate goals.

But implementing them will require careful consideration of costs, policies, behavioral barriers and technical impediments to determine which ones are the most promising for widespread use in Canada.

“The concept of natural carbon sinks has attracted a lot of attention in recent years for its potential to support climate policy, but their potential impact is complex,” said Dr. Eric M. Meslin, president and CEO of the CCA. “This report explores some of the barriers to implementation, as well as the benefits that could help inform improved ecosystem management and protection in Canada.”

The report also notes that the permanence and feasibility of various NBCS need to be carefully considered as well as co-benefits and trade-offs.

The authors indicate that attempts to enhance carbon sequestration in ecosystems across the country will require meaningful co-operation among multiple levels of government, as well as various industry and community stakeholders.

This includes the incorporation of Indigenous knowledge and leadership, including stewardship over land and water, especially as it relates to self-determination, self-governance and local environmental control.