One Earth Day tree can't absorb a carbon footprint
April 2016 - by Carolyn Dale
"My, how you've grown!"
I usually utter this fond and foolish phrase to children, but this time, it's to the tree I helped to plant on Earth Day, April 22, 25 years ago. This vigorous, 40-foot Douglas fir, thick with luxuriant branches, arrived at the house as a two-inch sprig in a pot the size of an eggshell, part of my son's second-grade nature project.
We found a spot for it in the backyard, planted it, and it has flourished ever since. The lesson then, as I recall, was about how trees absorb carbon dioxide (CO2), and, through photosynthesis, provide oxygen for humans to breathe. Back then, we were recycling, learning how to compost, cutting back on driving, and had only vaguely heard about a warming atmosphere.
Now, as our worries about the future of earth's climate intensify, stronger measures than planting a tree seem necessary, like solar panels, hybrid cars, and even cutting back on jet travel. That last step is a tough one to consider. I've only recently learned that flying produces such a heavy load of CO2, as jet fuel burns, that it's worse than car travel.
I gaze up at the tree's deep green branches and wonder how much this one tree is helping to mitigate my own carbon footprint, the amount of CO2 that I produce in a year of regular activities. The buildup of carbon-based gases in the atmosphere is blamed for a warming atmosphere and changing climate conditions.
Can this tree make up for the flying I do, let alone the driving? A healthy, mature tree at least ten years old absorbs 48 pounds of CO2 in a year, according to the Urban Forestry Network. That sounds good, and I'll guess our Earth Day tree takes in a healthy 50 pounds. Of course, this happens only while the tree is alive; when it dies, the process reverses.
I didn't realize that flying was so terribly polluting—much worse than a phalanx of cars driving those same passengers from place to place—until I read a recent article in Yes! Magazine by a climate scientist who has decided not to fly anymore.
Peter Kalmus writes, "Hour for hour, there's no better way to warm the planet than to fly in a plane. If you fly coach from Los Angeles to Paris and back, you've just emitted 3 tons of CO2 into the atmosphere, 10 times what an average Kenyan emits in an entire year."
Even a shorter, coast-to-cast round-trip flight apparently would add a whopping 1.5 tons of CO2 emissions to my footprint. That means I would need 60 of my tall, healthy Earth Day trees to make up for one such flight, each year. That's a lot of trees, and according to the Arbor Environmental Alliance, one acre of hardwood trees is needed to neutralize the carbon footprints of eighteen average Americans.
Kalmus goes on to ask why so many environmentalists, aware of the facts, still choose to fly so much. He writes that it took him three years to cut back completely on flying, and that not attending job-related scientific conferences in distant places has impacted his career.
Beyond work issues, flying is often a token of social and financial success; we do assign status for taking ever-longer trips to more distant and exotic destinations. And how will we pull back from this? It's hard to imagine that Americans might earn a new kind of social status by refusing to fly.
But I'm thinking about this because the climate news this spring seems especially grim. The World Meteorological Organization's annual report in March "pointed out that not only was 2015 breaking records on the surface, but also hundreds of meters deep in the ocean," according to the Associated Press. The article adds, quoting David Carlson of the World Climate Research Program, "And the first two months of 2016 were even hotter, so startling that they 'have sent shock waves around the climate science community.'"
Some of the effect is caused by overall warming combining with an El Nino pattern, so the rate of increase could ease as El Nino fades. Also, nations are taking united steps, such as the recent Paris agreement, in which 192 countries have put the world on a CO2 emissions diet, possibly giving us 20 to 30 years to start correcting climate-changing imbalance, according to news stories. And, the U.S. Congress is considering legislation that would place a surcharge on fuels that emit a lot of CO2.
I wonder how much that might raise the cost of jet travel. If it becomes more expensive, will we be drawn more to staying in our own backyards? Many people want to take personal steps to help correct environmental problems, and right now, I want my Earth Day tree to appease my conscience for my part in all of this. In fact, I'm going to go out, give it a hug, and wish it a good, long life.
For this tree has another lesson to impart, one we've rarely considered while watching it grow. It absorbs CO2 and wafts out oxygen only for the length of its life; when it dies, the decomposing wood will emit carbon dioxide back into the atmosphere. In fact, some research shows this CO2 will equal the oxygen it has created during its lifetime, yielding no net gain of oxygen over those decades.
This is a sobering lesson for this Earth Day, that the tree itself will be a neutral factor, over its lifetime. All along, I've been imagining that we've increased earth's oxygen balance by nurturing the tree, when it turns out the gain is only temporary. The tree itself remains true to the larger cycle of life on this planet, and the nature of that cycle is to maintain a balance.
We humans get attached to trees for reasons beyond the ineffable oxygen they produce. People plant trees as commemorations, knowing they will last a long time, even beyond a human life span. They signify home and anchor us in our place. I recognize our tree and the neighbors' tall firs and cedars from far away and use them as points of orientation when I return from long walks or distant trips. A family I know has planted a tree for each child and grandchild, and as the trees grow, the generations attach to this home, family and place.
That's another inspiration for revering this Earth Day tree shading my yard. If Americans travel less in the future and cut down on jetting off to one place or another, we might instead spend more time in our own backyards and value our homes, families, and trees, all that much more. Then we might show that the poet T.S. Eliot was right when he wrote, the "end of all our exploring will be to arrive where we started and know the place for the first time."
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