The topic of population is a fraught issue, with some folks identifying it as a key element of the climate crisis, while others see the risk of the issue being used against developing countries with high rates of population increase.

I have thoughts about this, many of which have been set forth in previous columns. But, for the purpose of this column, and possibly other future columns that focus on small changes that need to be made or are being made in response to the climate crisis, I don’t want to enter that fraught discussion directly.

What I do want to do is to bring attention to how even very small changes made in response to the climate crisis can involve substantial complexity when scaled from an individual action to one involving millions or billions of people.

Let’s start with air travel. As mentioned in previous columns, carbon emissions attributable to flying are substantial and increasing. It just takes lot of jet fuel to move those incredibly heavy planes around the planet.

The New York Times did a serious evaluation of the greenhouse gas emissions from flying their travel department around to visit the places they write about. Now, they’ve followed up with an examination of a smaller but related issue: onboard waste produced by the approximately 4 billion passengers who fly each year.

According to the Times (and, actually, this whole column is mostly based on an Oct. 14 article), although no one actually knows how much waste is produced as a result of air travel, there are a few narrow studies that, if extrapolated, estimate the magnitude of the problem.

The International Air Transport Association looked at air travel through Heathrow Airport in England and estimated that “airlines generated about 6.7 million tons of cabin waste” in 2018.

What’s the waste, you might ask?

The UNESCO Life Cycle and Climate Change research group took “an even deeper dive into the issue of airline trash” to answer that question. They analyzed “approximately 8,400 pounds of garbage on 145 flights into Madrid … and found that 33 percent was food waste, 28 percent was cardboard and paper waste, and about 12 percent was plastic.” (Hmmm, what’s the other 27 percent?)

Items identified as waste include plastic spoons, forks and knives, the trays meals are served on, leftovers from the meals themselves, beverage containers (milk, wine, etc.), plastic cups, wrappings, stir sticks, toilet waste and disposable headphones. All this adds up to an estimated 3 pounds of waste for every passenger.

There may be financial interests involved in maintaining the status quo. According to the article, in order to not antagonize the agricultural community that supplies airlines with meals, “even untouched food and drink, which, according to IATA estimates, makes up about 20 percent of total airline waste, ends up in landfills or is incinerated.”

The airlines are responding, but are concerned that any changes not increase the weight of the plane since that translates directly into more fuel usage, thereby increasing both cost and emissions.

So what are airlines doing or thinking about doing? Air France has pledged to “eliminate 210 million single-use plastic items like cups and stir sticks by the end of this year.” Quantas experimented with one commercial flight that produced “no landfill waste” by, among other things “serving meals in containers made of sugar cane with utensils made from crop starch.” United Airline s experimented with “meals using fully recyclable or compostable service ware.”

Hmmm, lots of experimenting but not as much actual action as yet. Why not? Recycling is simple. Composting is simple. So what’s the complexity?

There are many practices and costs embedded in the current structure of the airline industry. Airplanes aren’t set up for onboard recycling, so virtually all of the waste ends up in landfills. Any waste reduction solution will require cooperation and collaboration between the airlines, airports and catering companies.

Also, while there are international rules governing cabin waste, mainly intended to prevent the spread of disease, the situation is further complicated because “rules governing cabin waste are also subject to the regulations of the country” in which a plane lands. So, a jet traveling a route that lands in more than one country may be subject to different requirements and procedures for managing the waste produced by us passengers.

And, of course, volume, or scale: Just changing from one kind of meal presentation to another for 4 billion passengers involves costs, developing alternative supply chains, altering menu options, perhaps redesigning the airplane kitchens, installing a system and facilities to sort waste onboard, changing food delivery containers and/or the vehicles that move them on and of planes, etc.

As of now, many of the potential changes are observable at the Design Museum in London with an exhibit titled “Get Onboard: Reduce. Recycle. Rethink.” Exhibits include a lightweight food tray made of coffee grounds and husks, dishes made of pressed wheat bran, instead of multiple utensils, a “spork” made of coconut palm wood, a “waste product that farmers would otherwise burn,” and transparent lids made from pressed banana leaves for salads and side dishes (people want to see the contents).

— John Mott-Smith is a resident of Davis. This column appears the first and third Wednesday of each month. Please send comments to

Crossposted from the Davis Enterprise

Published online on October 16, 2019 | Printed in the October 16, 2019 edition on page A7