Tools and Tips
Meaning of net zero
June 4, 2021 | Charles Lin

Images by Chris LeBoutillier and Brigitte on Pixabay
You probably know driving a gasoline-powered car emits carbon dioxide (CO2), a heat-trapping greenhouse gas that contributes to global warming. In addition to transportation, activities in many sectors of our economy currently emit CO2, including agriculture, heavy industry, and production of electricity. Much of the energy that we use currently come from fossil fuels – coal, oil, and gas. Net zero emissions mean any addition of CO2 to the atmosphere is balanced by removal from the atmosphere of the same amount, resulting in no net addition. Net zero emissions is also referred to as carbon neutrality.
Why is net zero important? Climate science tells us global warming depends on the amount of CO2 added to the atmosphere through our activities. As long as we add CO2, warming will continue. To stop the warming, emissions must be reduced considerably, and any remain carbon emissions be balanced by its removal.
It is easier to decarbonize (i.e., reduce carbon emissions) some sectors compared to others. For example, driving an electric vehicle instead of a gasoline-powered car, or producing electricity using renewables such as wind and solar instead of fossil fuels, would considerably reduce emissions. But there are some sectors where decarbonizing technology is not yet readily available, such as cement and steel production. To reach net zero for these sectors, we must remove any emissions that result.
There are two approaches to removing CO2 from the atmosphere – through technology or nature. Carbon capture and storage technologies are being developed, but are not ready to scale up. Nature-based ways include planting more forests as trees and plants absorb CO2 as they grow; a challenge is the amount of land required and the need to not remove the forests once they are in place. There is ongoing research on both approaches.
What does this mean for Canada? The federal government has committed Canada to reach net zero by 2050 to help stop global warming. Reaching this goal will be a challenging task, as our economy is still very dependent on fossil fuels. Government leadership, private sector participation, community action, and engagement of Canadians are needed in an all-hands-on-deck approach. Our energy system and economy will need be transformed to reach the goal, in ways that maintain prosperity and well-being of Canadians.

Charles Lin
Charles is a retired atmospheric scientist based in Toronto. He stays busy as founder and lead of ImpactNetZero, keeping healthy in mind and body, and reading stories to his two grandchildren.