Evaluation of the Potential of Trees to Sequester GHG Emissions from Daily Car Travel. The Case of Montreal, Canada

Abstract

GHG emissions are an increasingly critical issue for cities and countries. Reducing them is important but evaluation sequestration potential, namely by trees, is also relevant to assess how many would be required to reach carbon neutrality and even carbon negativity, that will, at some point be required. This study aims to evaluate whether the number of trees planted in different boroughs of the city of Montreal is sufficient to balance the carbon emissions from car trips by residents of the Greater Montreal Area. It also proposes the use of the number of trees as a metric to assess the balance between GHG emissions and the carbon sequestration potential of trees. Thus, taking carbon neutrality as a goal, this paper quantifies how many public trees are needed to sequestrate the carbon emitted by weekday car travel, who should plant the trees, and in what area they should be planted.The results show that public tree planting is highly insufficient to sequestrate the carbon footprint of car travel, and that achieving carbon neutrality by planting trees in the city alone is unfeasible because of the space required. Therefore, maximizing the modal shift to active modes would reduce this imbalance, but not enough. This means that much more radical changes must occur to move towards a balance.

Keywords: carbon sequestration, urban trees, GHG emissions, car driving, vehicle-kilometers