Does it add up?

Nearly 200 guests came to The French Retreat last year. Some of our French visitors came by train but the majority flew from the UK, with some flying to or from Amsterdam, Italy, Spain, Greece and the Middle East.

 

According to the carbon offsetting site MyClimate one return flight from London Gatwick to Bordeaux is responsible for producing a third of a ton of C02.

Another way to look at this sum is passenger miles per gallon (PMG) Two sources stated that typical airline PMG is about 78 miles per gallon. The distance from Gatwick to Bordeaux  is 437 miles but most airlines fly a less straightforward route so they’re never more than a few hundred miles from somewhere to have an emergency landing. If you say that adds 10% distance to the flight, it’s 6.16 gallons each way. And that produces a little over 370 pounds of carbon dioxide. A single tree absorbs about 48 pounds of carbon in a year, so you’d have to plant 8 trees.

According to NC State University A tree can absorb as much as 48 pounds of carbon dioxide per year and can sequester 1 ton of carbon dioxide by the time it reaches 40 years old. But depending on where and how they are planted not all trees make it to 40 years old.

Michael Barnard, Chief Strategist at TFIE Strategy Inc. says: "For a New York to Berlin flight (3965 miles), you would need to plant 11, 21 or 213 trees, depending on how you choose to consider the sequestration capacity of planted trees. If you go with a robust tree planting carbon offset program, 11 is most likely. If you stick a seedling in a field and walk away, I'd go with 213. If you stick a seedling in a decent field, properly spaced in a place unlikely to be lumbered and walk away, I'd go with 21."

In more details his sums depend on whether you consider a single year carbon abatement (very conservative), half a tree lifetime of carbon abatement or a full 40 years of tree carbon abatement). Many programmes follow up on planted trees and certify that they are sequestering the full carbon lifetime, including planting new trees if a tree dies for any reason.

Assuming one year load: 4,675 kg / 22 kg = 213 trees (rounding up)
Assuming median life: 4,675 kg / 228 kg = 21 trees (rounding up)
Assuming full life: 4,675 kg / 455 kg = 11 trees (rounding up).

Based on these calculations with a properly managed planting programme we are aiming to plant one tree for every 360 miles flown. That's one tree for each London to Bordeaux flight. 

The problem with using trees to absorb CO2 as an answer to global warming is that the acreage needed for the trees bumps up against limits of arable land on the planet. We have an acre at the French Retreat, plus a few neighbouring acres of arable land we would like to plant trees on. But it's a start. Will you join us?