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Couldn't we achieve negative carbon emission simply by build all houses from wood? Cut down all grown trees and replace them by young ones. The houses act as

Couldn't we achieve negative carbon emission simply by build all houses from wood? Cut down all grown trees and replace them by young ones. The houses act as carbon sinks. The young trees capture more co2 than the old trees. Easy. Takes little technology, but does take up land. Probably we need all alternatives too, but this seems low hanging fruit to me.

kanjus 8y ago
The theory that young trees capture more CO2 than older trees has been debunked as far as I know. The best carbon sinks are older large trees: they grow at lower rates height-wise, but faster mass-wise, sequestering much more carbon. A single large tree might add the same amount of carbon to a forest within a year as is contained in an entire mid-sized tree, I’ll add some sources later
- 205guy 8y ago
  I read once that the highest density of living entities on the planet, measured in weight per surface area, are the Sequoia groves in California. That is, the mature ones that escaped logging. Now, I'm not sure we can consider the entire tree to be alive, but relevant to this discussion, they are almost entirely composed of atmospheric carbon, tons and tons of it quite literally. In all practicality though, I think sequoia and redwoods are more difficult to grow and have limited climate tolerances (an issue when the the climate is changing). I wonder if go fast-growing tropical trees such as albezias or others would be better. But we should also be looking for 3-4 ideal trees for each climate zone or better yet, trees adapted to several zones.
aoner 8y ago
Afforestation is part of the solution but even if we would plant a lot of trees and not use them, this solution does not scale. Current most optimistic estimates think trees can sequester 600 GtCO2 by 2050 max while most estimated think this is around 100 GtCO2 or less. We'll probably need around 1000-1500 GtCO2 of negative emissions. So yes we need to plant more trees, but we also need to pursue other negative emission technologies such as ocean fertilization/ocean liming, soil carbon sequestration, direct air capture and enhanced weathering.

kanjus 8y ago

The theory that young trees capture more CO2 than older trees has been debunked as far as I know. The best carbon sinks are older large trees: they grow at lower rates height-wise, but faster mass-wise, sequestering much more carbon. A single large tree might add the same amount of carbon to a forest within a year as is contained in an entire mid-sized tree, I’ll add some sources later

205guy 8y ago
I read once that the highest density of living entities on the planet, measured in weight per surface area, are the Sequoia groves in California. That is, the mature ones that escaped logging. Now, I'm not sure we can consider the entire tree to be alive, but relevant to this discussion, they are almost entirely composed of atmospheric carbon, tons and tons of it quite literally. In all practicality though, I think sequoia and redwoods are more difficult to grow and have limited climate tolerances (an issue when the the climate is changing). I wonder if go fast-growing tropical trees such as albezias or others would be better. But we should also be looking for 3-4 ideal trees for each climate zone or better yet, trees adapted to several zones.

aoner 8y ago

Afforestation is part of the solution but even if we would plant a lot of trees and not use them, this solution does not scale. Current most optimistic estimates think trees can sequester 600 GtCO2 by 2050 max while most estimated think this is around 100 GtCO2 or less. We'll probably need around 1000-1500 GtCO2 of negative emissions. So yes we need to plant more trees, but we also need to pursue other negative emission technologies such as ocean fertilization/ocean liming, soil carbon sequestration, direct air capture and enhanced weathering.