BC's forestry sector could deliver significant carbon reductions - but climactic wildcards are at play.
British Columbia’s CleanBC climate strategy identifies waste from forestry, agriculture and residential areas as potential sources for bioenergy, with a goal to produce hundreds of millions of litres of renewable gasoline and diesel by 2030. Furthermore its Wood First policy aims to increase the proportion of harvested wood used in long-lived products (LLP) that store carbon, such as buildings.
Werner Kurz, a senior researcher with Natural Resources Canada, leads a team that is helping policymakers understand how the forestry sector can help deliver on those objectives, among others. He heads up the Forest Carbon Management Project, a PICS collaboration including scientists from UBC, British Columbia’s Ministry of Forests, Lands, Natural Resource Operations, and Rural Development, and the Canadian Forest Service.
“We need to understand the carbon retention and storage in wood harvested from BC forests,” says Kurz. “In the built environment, this presents opportunities to reduce our use of concrete, plastics, and steel, which all have emissions impacts,” he adds.
The 35 Per Cent Solution
When coupled with region-specific forest management practices, the emissions reductions could be significant. Under the best case scenario modelled by the researchers, they concluded that BC’s forestry sector could potentially contribute 35 percent of the province’s 2050 emissions reduction target (of 80% below 2007 levels) at costs well below $100 per tonne of carbon dioxide equivalent (CO2e). In other words, BC’s forestry sector could deliver 18.2 megatonnes of CO2 equivalent of the required 52.7 MtC02e reduction in the province’s annual emissions, while also creating 2,000 new full-time jobs, among other economic benefits.
This could be achieved, in theory, by applying regionally targeted carbon reduction strategies to forest management practices and forestry products. In practical terms this means measures such as extracting more wood from harvested areas, harvesting less in other areas, using waste wood to create bioenergy instead of slash burning, and substituting more long-lived wood products in place of carbon-intensive steel and concrete. The regional approach is critical, the researchers found; climate impacts will vary across the province, and forest management needs to anticipate these future impacts.
However, the researchers also acknowledge that wildcards such as drought and wildfires could wipe out carbon reduction gains. Climate change is already impacting the region’s 55 million hectares of forest lands, with some wetter areas benefiting from the warmer conditions and increased carbon dioxide levels, while drier areas are experiencing slower growth and increased tree mortality. The risks of forest fires and other disturbances such as new pests and diseases are also increasing as the climate warms.
Mapping Down to the Hectare
The analyses continue; the team can now simulate forest-carbon dynamics, and GHG emissions and removals, down to the hectare level—across almost all of British Columbia. It’s using the model to quantify forest climate-mitigation opportunities as far out as 2070.
“Increasingly, the policy community is understanding the role of the land sector in contributing to greenhouse-gas removals, but also the risk of increased emissions from climate-change-induced wildfires,” says Kurz. “Our team’s ongoing research is designed to inform that discussion.”
Link Hember, Robbie A. and Kurz, Werner A. and Coops, Nicholas C. Increasing net ecosystem biomass production of Canada's boreal and temperate forests despite decline in dry climates. Global Biogeochemical Cycles vol. 31, 2017
Link Kurz, Werner A. and Smyth, Carolyn E. and Lemprière, Tony C. Climate change mitigation through forest sector activities: Principles, potential and priorities. Unasylva vol. 67, 246, 2016
Xu, Z., C.E. Smyth, T.C. Lemprière, G.J. Rampley and W.A. Kurz. 2017. “Climate change mitigation strategies in the forest sector: biophysical impacts and economic implications in British Columbia, Canada.” Mitigation and Adaptation Strategies for Global Change, pp 1-34.
Hember, R.A., Kurz, W.A., Coops, N.C. 2016. Relationships between probability of tree mortality and surface water balance across North America. Global Change Biology 23 (4): 1691-1710.