It’s become somewhat of an overdone question. In a world of increasing urgency to fight back against climate change, we are pushed to take a more insightful and critical eye to our day-to-day activities and the effects they have on earth. A question I get asked at least once a week is something along the lines of “how many trees do I have to plant every year to offset my car emissions?” This question is almost never followed up by any further information but the responsibility falls upon me to reply.
Firstly, I want to proclaim that I am not a climate scientist. I am not a scientist at all! But I do have a special interest in a greener way of living. And I do love learning new things. So when I do get questions like this, I am happy to spend a bit of time with a bunch of numbers to answer as best I can. Of course with the disclaimer that I am not qualified nor do I have the required information to answer with accuracy how to offset your car’s carbon emissions. I can point you in the right direction though!
WHAT’S THE DEAL WITH CARS?A DIP IN THE POND OF CARBON EMISSIONS
Carbon emissions are a tricky subject. As with everything, it depends on so many little, tiny factors that are specific only to you. When dealing with calculating the carbon emissions of your car, you would have to consider: what type of car you have, how much you drive it, how you drive it, what kind of climate you drive in, what kind of roads you drive on, how many people are in the car, what type of fuel you use...it goes on!
But not to get too down, you can get a general idea based on some easily available statistics. The EPA advises that a typical passenger car emits, on average, about 4.6 metric tonnes of carbon dioxide per year. This figure is based on a fuel economy of 22 miles to a gallon with an average yearly travel of 11,500 miles.
Furthermore, as of March 2018, the EPA states a tree can offset 38 pounds of carbon dioxide every year and will have sequestered 1 ton of carbon dioxide when it reaches 40 years old. This is a little bit confusing since this is measured in short tons which is equivalent to 0.907185 metric tonnes.
If you’re anything like me, you left math back in high school. I like to figure things out but have a tendency to get confused by numbers and especially the conversion between weights. So, how can we simplify all of this?
So let’s look at it this way: if you plant one tree, over its lifetime you are sequestering just under 1 metric tonne of carbon dioxide. To offset 4.6 metric tonnes, which is equivalent to 5.07 short tons, you would need to plant at least 6 trees every year to offset your car’s carbon emissions.
As I said earlier, this is a very basic estimate in an equation that has numerous different variables in reality. That being said, it is important that we all do our part to offset our emissions while also aiding our forests.
In short, simply planting a bunch of trees isn’t going to offset your carbon footprint fully. But it will make a difference. Every little action counts.