Alarm Bells, Sanity Check

Years ago I witnessed, first-hand, the effects of deforestation – first from a major hurricane, then from an ensuing crush of land development.? Among other effects, the local weather changed after the loss of so many trees.? The impacts were seen over a county-wide area and were, in some cases, severe.

And so, at a young age I became convinced of the value of trees, and of tree planting and reforestation.

On January 31st of this year, ScienceDaily published an alarming Penn State study (https://www.sciencedaily.com/releases/2024/01/240131183540.htm) that, for many, called into question tree planting, itself. ?Researchers found that trees stressed by an overheated atmosphere are unable to use all the carbon they take in – “coughing” some of it back up into the air at night.

Because carbon dioxide is a potent and long-acting greenhouse gas, these findings were grim.? Since trees build their mass using carbon, most of us have understandably seen trees as essential tools in fighting global warming.? This has now been thrown into doubt.? Several media outlets seized on the Penn State findings and drew even direr conclusions.? Those included the suggestion that trees and tree planting would make climate overheating worse.

I’d like to plead for a moment of sanity here.

The direst prediction first:? That idea that trees will make climate overheating worse.? The very carbon that those stressed trees release at night, is already present in the local atmosphere.? That carbon is simply returned to where it was before -- not created by the trees as additional.? Also, until and unless the trees are exterminated by drought/stress/whatever, those trees are going to remove some carbon and use it in their growth.? So we still have a net benefit, compared to no trees at all.

Second:? A new strategy is already being employed, in parts of the U.S. and elsewhere, that may seriously help trees help the Earth in the ongoing climate fight.? It’s called “assisted migration.”? As regions continue to grow warmer, trees preferring cooler conditions are replanted, in zones that used to be too cool for them but which now are becoming “just right.”? Likewise, trees used to warmer conditions are seeded or planted into spaces being vacated by the more-temperate trees.

Even in the Tropics, there are tropical trees and then there are “ultra-tropical” trees that want to be warm both day and night.?

Don’t get me wrong:? All trees (and all living things) have their temperature limits.? And we do appear to be creating some climate zones in the Tropics that are more and more hostile to life...all life.? I'm not suggesting that tree planting can magically defuse global warming.? Measured global atmospheric carbon continues to march higher.? We need to be smart in our choices, and to do more to tackle the carbon glut.

I just don’t want to see people throw the baby out with the bathwater.? The Penn State study, and others that have addressed this issue, are alarming.? But trees – and green life – continue absorbing carbon. ?The average mature tree is estimated to sequester around 48 pounds of carbon per year (https://www.arborday.org/trees/treefacts/). ?Trees are still a force for good in this world – including where the climate is concerned!

If you will, do a bit of reading about how the climate has warmed in your area lately; ClimateCentral.org has stats and links (https://www.climatecentral.org/climate-matters/shifting-planting-zones-2023).? If you’re in the U.S., the USDA has redrawn our climate zones to reflect that warming (https://planthardiness.ars.usda.gov/. Half of the U.S. zones have seen a measured shift northward, reflecting warmer winter minimum temps).? Then, consider using what you’ve learned, to pick out the right trees for your climate.?

If giving to a tree-planting nonprofit, look for ones that rank well with Charity Navigator (https://www.charitynavigator.org/) and other feedback sites, rather than just relying on search advertising.? Look for website data where the nonprofit discusses science-based planting.? A diverse set of species used in different plantings is also a good sign.? Email the org, if you still have questions.

The media coverage around studies like Penn State’s, makes a case for careful inspection of alarming stats.? In the case of trees, our leafy friends have been removed from the realm of magical bullet.? But trees are still a necessary – and wonderful! – part of the solution to climate change.? And for people, wildlife and ecosystems, trees offer so many benefits. I hope you’ll join me in fighting CO2, in reforesting, in creating natural habitat…in tree planting.? Thank you.

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?2024 - Jack V. Thompson