The US per-capita CO2 emissions is around 17 metric tons. For a family of 4, let’s call it 70T of CO2 emitted.
There’s the direct contribution and the indirect contribution to consider. The direct contribution is how much you can directly control. For example, you can chose to turn on the air conditioning. Or you can chose to get on a flight. Or drive the car.
The indirect contribution are things done on your behalf. For example, as I type this, the 24-hour store down the street is open. It’s open for me, even though I might only go there once every 3 days. Or the fountain at the mall is running for me, even though I might only view it once every 3 weeks. Or the new Seattle 99 tunnel. I might drive on that every 6 months, but it was built, partially, for me.
The indirect is very hard to control. But the direct is very easy to control. What is our approximate direct contribution? For most, it’s from 4 sources: 1) Home energy, 2) Driving, 3) Food 4) Flying.
Our home energy use is responsible for around 1.3 tons (T) of CO2 (source). Driving 25K miles annually (2 cars) generates about 9 tons of CO2 annually (source). Your food footprint is around 2.5 tons per person, or about 10 tons per family (source). Now, these numbers aren’t quite apples to apples, because the home energy figure is the average of all households (including single person living in 800 square foot studio apartment), and we’re looking more at family of four type figures, and more affluent families at that. For that, we’ll adjust the home energy figure to 3 tons, and we get the following: 3 + 9 + 10 = 22 tons. In other words, the country produces 70 tons of CO2 per family of four, but the family can control about 22 tons of that. The rest of that is what we covered above—the indirect. That’s the 24 hour store keeping their lights on 24x7 and concrete factory making cement for the new high rise in NYC you will someday visit.
So, if we can directly control about 22 tons of that, how much is flying? Previously we looked at “what is your ‘fair share’ of CO2” and noted a coach flight from Seattle to Paris is about 3T of CO2 per passenger. In fact, all up, flying emits about 2X the CO2 of driving for a given distance (that should make sense because doubling your speed quadruples the drag, and an airplane at 500 MPH is traveling 7X faster than a car at 70 MPH).
An affluent family of 4 that takes the family on a round trip to Europe is looking at 6T per person, or 24T for the family. In fact, that’s about what they were budgeted for the entire year of living. In other words, taking the family of 4 on an overseas vacation is devastating from a CO2 perspective.
If you are flying, everything else you do for CO2 is erased by the flying. You cannot possibly recycle enough. You cannot possible install enough solar panels.
Who is flying?
Most affluent people think that everyone flies. And they see the common statistic that flying is just 2% of our global CO2. In other words, they think, flying isn’t bad.
But globally, very few people fly. A recent study provides some data on the US population. Key points:
19% of US adults have never flown. Ever.
45% of US adults have flown in the last year
The average number of trips for all US adults is 2.1 trips.
6% of the US population takes 9+ trips per year.
Half of all flying is for leisure.
In the US, we know that there are 916M paying passengers that got on a plane in the 12 months ending September, 2019 and we know they flew 1T miles. That’s an average of 1000 miles per trip for domestic flight. An average round trip flight is thus 2K miles. And it’s growing, with 2019 hitting another all time high in domestic air travel.
Globally, some 4B passengers are flying each year. And as the 7B on the planet experience growing income, they’ll all want to fly too.
If the entire world flew as the US flew, instead of a population of 300M making 1B flights per year, we’d see 7B people making 23B flights per year instead of the current 4B flights per year.
Can flying be made CO2 neutral?
Not likely soon. Lots are working on it. But regardless, this won’t happen quickly because of the scale required and momentum in place.
If you fly, you are part of the problem. Worrying about water bottles or whether to place the pizza box in the recycle or trash bin as you book your next vacation is an engineering contradiction beyond words. Tough to hear for sure.
Think of it this way: A mile of flight emits about 100g of CO2 per passenger. A 500 ml one-time-use water bottle is 10g of plastic, which kindly equates to 10g of CO2. Each mile of flight is the CO2 equivalent of 10 water bottles. If the plane is flying 500 MPH, that’s one mile every 8 seconds. That’s the equivalent CO2 of about one water bottle per second per passenger when you fly commercial.