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Given the assumptions that:

  • emissions of CO2 are indirectly contributing to global warming
  • CO2 is captured in the bodies of trees during their lifetime
  • CO2 is released from the bodies of trees when they burn or decompose

It follows that if we prevent the bodies of trees (wood) from decomposing by producing durable consumer products (e.g. furniture) we are actually preventing CO2 emissions. Is this reasoning correct?

gerrit
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Martin Drozdik
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    Buying used furniture that is slotted for compost or burning is helpful to some super-small degree. However, planting a tree would be a little more helpful. Cutting energy usage is the best thing you can do to help... it's the energy and shipping industries that are most influential on global warming. –  Feb 20 '17 at 22:20

1 Answers1

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On first thought I was tempted to say yes, because you are creating a longer-living carbon sink for part of the wood (compared to letting the tree die naturally).

But on second consideration: Look at the amount of material that gets discarded when making wooden objects. I estimate that's easily 70% of the tree: 30% in the construction phase alone, plus cutaway outer edges, branch and root material. That fraction is going to be processed much faster (cheap wood board materials, wood pellets for burning, sawdust, etc), so it hardly counts as a carbon sink.

So the total effect is you cut down a mature tree, plant 2 saplings in its place, put 30% of its carbon in your furniture for 50 years, and dump 70% of its carbon back into the atmosphere almost immediately.

That looks to me a destroying a carbon sink. Better leave the tree standing.

Notes:

  • I'm assuming that you cut down the tree before the end of its natural life (otherwise the wood would be useless), and that the furniture outlives the period the tree would have lived on. Any deviation from that makes matters worse.
  • For a good comparison you would have to make a graph like below (time on horizontal axis, graph trees representing objects, their width representing carbon content), with calculations about tree type, tree and furniture volume, time stamps, etc. That would be quite an undertaking (and many quantities would have to be assumed since the question does not have them either).

enter image description here

  • What about when compared to metal and plastic furniture? – LShaver Feb 21 '17 at 14:47
  • @LShaver That's a new question and needs a far more complex life-cycle analysis. Not really doable with 'original research' - only answerable if someone has already done that and we can find a reference. –  Feb 21 '17 at 15:29
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    Good point, though I doubt the choice is rarely between wooden table and eating off the floor. And, even if only 30% of the wood ends up in the furniture, if this is preserved long-term it is better than 100% of the tree rotting on the ground (considering only CO2 emissions, not ecological impacts). So the question is, how much CO2 is emitted turning that 30% into furniture, and is it more than the wood stores? – LShaver Feb 21 '17 at 18:35
  • I agree with what you've written, but I think your answer only holds if fewer or no trees are replanted. What if the tree is from a well-managed forest where trees are replanted? Or if the tree died of old age? – THelper Feb 22 '17 at 08:09
  • Why does that 70% have to go back into the atmosphere straight away? Surely, that depends on what is done with it? If you were to bury the sawdust it would take a very long time to release its carbon back into the atmosphere (and not all of it would be released back). You also have to consider other possible uses for those by-products - sawdust can be used for fuel (which granted does release the carbon back instantly) but potentially supplants the use of fossil fuels. – George of all trades Feb 28 '17 at 14:42
  • I would also second @LShaver comment - it isn't a choice between wooden furniture and no furniture, it a choice between wood and other materials, in which case I would be surprised if wood did not massively surpass other materials in terms of sustainability. – George of all trades Feb 28 '17 at 14:42