Trees are overhyped when it comes to CO2 capture/recycling. Algae already outproduces trees globally by 2x. It is also much easier to industrialize. For example, algae ponds could be built alongside fossil fuel plants to capture carbon on site.

Oil is predominately captured algae that died, sank to the bottom of the ocean, and was sealed in by salt deposits/other nonpermeable layers. Coal is carbon captured by trees, but it only formed in a relatively narrow period after cellulose evolved but before bacteria/fungus evolved to eat it. Oil will continue to form, but it's unlikely any new coal will form in the future.

https://academic.oup.com/bioscience/article/60/9/722/238034

In theory younger trees should consume more CO2 as they are still growing. Older trees that are maintaining a steady state should consume a net of almost 0 CO2.

Exactly. That’s why sustainable forestry is a great way to capture both CO2 and building materials, which will store the carbon for decades.

It's not all about CO2, preserving habitats and biodiversity is another concern.

There’s a lot of underhandedness in how climate change is marketed to mass audiences that I think we could do without.

We’re in the midst of the 6th known extinction event, which is caused by human activity. I’m sorry if the “marketing” seems underhanded.

If humans don’t mitigate climate change and habitat destruction, life on earth will get a lot harder.

I’m sorry that the marketing isn’t convenient for you.

But the 100 year old tree that was removed (and everything growing on it and in the soil near it) added a lot of CO2 to the air, and it's unlikely that was grows back now will be as rich in biodiversity and CO2 binding capacity than the old one.

Forgive me if I misunderstand, but the carbon is in the 100 year old tree and when it's cut down and turned into something it's still there. So that carbon is sitting the walls of a house, furniture, or sheafs of paper, isn't it?

Disregarding cutting the tree down to just burn it for heat, obviously.

Yes, if it's in a house or furniture it will be safe for a while longer.

> Older trees that are maintaining a steady state should consume a net of almost 0 CO2.

They are a storage of CO2. If we replaced all old trees with new ones we will gain a lot of potential for CO2 capture but at the cost of releasing massive amounts of CO2 to the atmosphere.

You are right. But I think that the point was to notice that we may have lost many good trees even if we are trying to add new ones.

The CO2 is only released if we burn them. If we use the wood for building materials or other goods with long-term storage, the carbon continues to be locked up.

And if we let them growing and rooting for another 100 years instead we would have a much faster CO2 sink.

Many trees grow continuously until they literally kill themselves with unsustainable weight.

Big trees likely add more biomass per year than young trees

I would expect plants to genetically encode growth limits, because a mature tree that continues to stand and produce seed will reproduce more than one that falls over prematurely because it never stopped growing.

Does any life form on Earth grow indefinitely?

This would not matter, because a dozen of those trees still weight like 0,00001% of what the old tree has stored.

The writer is clearly conflating canopy coverage area with individual trees.

What would be a better measure? Tons of carbon locked up in the wood? The amount of carbon they can remove from the atmosphere on an average day?

Canopy coverage is a fine measure. It's equating the number of trees with canopy cover with carbon sequestration which is at issue. The original study isn't what I'm commenting on.

eg, Younger forests are not as productive as older forests when it comes to carbon sequestration.

yes, and yes.

How would you measure this with accuracy and cost efficiency?

Is canopy reasonable enough after a certain percent increase (say, 5% increase)? We are talking about percentages of the Earth's dry land, so nontrivial certainly.

> How would you measure this with accuracy and cost efficiency?

Does not seem like an impossible task, I see two preliminary ways at least to attack the problem, but probably both will be wrong and is not my job to measure this without resources in any case

> not my job to measure this without resources in any case

Ah, I misunderstood. I thought perhaps you had some insight here based on your insistence that canopy is a bad metric.

So canopy is definitely measurable at low-ish cost via satellite monitoring. I would presume it wouldn't be hard to add reasonable time-series based assumptions on new growth and make calibration adjustments that take into account the evolution.

Going into a forest and sampling, everywhere, is going to be cost inefficient relative to a model that can be based on canopy and calibrated on sub-samples of forest sampling, both historical and recent expeditions.

At least, that's how folks who would do this kind of job would likely approach it, based on my experience in similar domains. When it comes to funding, academia is a brutal place where resources are slim. Obvious adjustments are the next-best low hanging fruit to original development -- so a direct canopy measure would next likely be iterated to account for new-ness of forest and carbon sequestration calibration.

Though I don't think looking at e.g. Pando and adding one to your count is particularly useful in this context.

Yes. And I’m willing to bet that biodiversity is not so good in many of these “forests” which should probably be called something like “plantation”.

Someone advocating direct air carbon capture made this strong argument that stuck with me: Carbon released by drilling oil didn't come from trees. So recapturing the carbon from what we think was released from trees burned down before does not include carbon stored underground.

Maybe they applied the principle of: little trees, fresh as a breeze.

Maybe not.