Trees

In my twenties, while in graduate school, I took a six-week trip paddling canoes with five other colleagues to the Arctic Circle. I will never forget the first week or so where, in the pristine wilderness of central Canada, we heard nothing but chain saws during the long arctic daylight. The rivers had a buffer of several hundred yards where trees could not be felled, but beyond that zone, it was cut cut cut. One Sunday edition of the New York Times requires five acres of Canadian pine woods to print.

One cubic meter of wood weighs about a metric ton (or a cubic yard of wood 3’x3’x3’ weighs about one US ton). It sequesters as much carbon as burning 350 liters (slightly less than 100 gallons) of gasoline*. We need to pay attention to burning of fossil fuels and release of methane. It is true that our planet has recovered from various periods of intense volcanic activity and atmospheric warming, but each time, the recovery period lasted tens to hundreds of thousands of years. Anybody care to wait around and see what happens?

Then I stumbled upon an inconvenient fact. Mature pine trees actually EMIT MORE CO2 than they sequester. In maturity, trees are not growing and increasing their size which absorbs CO2. They produce only pine needles and leaves which fall to the forest floor for decomposition. Decomposing biomass (such as pine needles) emits CO2. If the goal is to absorb (sequester) CO2, then the way to do it is to grow trees in managed forests until they reach maturity. At maturity, turn them into wooden buildings and replant.

Aesthetically, I don’t like this, but which alternative is better?

    • A – Managed forests that can be used for parks, hiking, recreation and even space for transportation
    • B – Open pit mines for limestone (to become concrete) and vast mining operations for iron ore (steel).

As an example, for B, a global mining company was recently found guilty of dynamiting caves in Australia that contain the earliest fossil and cultural artifacts of human habitation on the continent going back nearly 50,000 years. This erasure of priceless archaeology was done so the mining company could get to an iron ore deposit faster.

The use of steel and concrete in construction globally accounts for about 15% of all greenhouse gas emissions. Every year, the world produces enough concrete for construction to cover all of England four inches deep!  With modern, engineered wood products such as “Cross Laminated Timber,” we can build strong commercial buildings up to nine stories high with wood that absorbs rather than emits CO2. This is one way the world of the future can atone for the sins of the past by building smarter with materials that fix the problem instead of making it worse.

We are way past the point of politicizing science and letting climate change deniers have their say. I have been reading the scientific papers and watching this slow-motion train wreck unfold since I worked in an atmospheric physics lab as an undergraduate in 1971. The climate is changing in a direction that will cause widespread human suffering and death. Correction of the problem will take decades. Politicians taking snowballs onto the senate floor will only make the future worse for our grandchildren. If the church doesn’t speak out against the major moral and existential issue of our time, then what good is it?

*Fun, sidebar calculation: If you drive a car 15,000 miles per year, and your vehicle gets 20 miles to the gallon, then planting and managing 8 trees (after they are 4” in diameter) will offset your fossil fuel emissions. Seriously, tree planting and management is one of the best solutions to climate change we have.


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