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Forests and carbon capture
Forests and carbon capture
#1
Remember how I keep telling people to check the numbers, get the facts, and don't listen to people who have a vested interest in getting you to think their way?

Well, here's a worked example of that approach.

Canada's forests actually emit more carbon than they absorb — despite what you've heard on Facebook

Which is simple logic, after all. The carbon that a tree takes into itself while it's growing gets released when it dies and decomposes - and (thanks to wildfires and insect infestations) there have been a lot more trees dying than being planted in the last couple of decades.

Does anybody have relevant statistics for other forests?

If you want to use trees to sequester carbon, you have to keep them from decomposing after they die. Build buildings out of wood, Buy and use wooden furniture. Buy books instead of using the Internet for everything - and keep the books (preferably on wooden bookshelves). And so on.
--
Rob Kelk

"Governments have no right to question the loyalty of those who oppose them. Adversaries remain citizens of the same state, common subjects of the same sovereign, servants of the same law."
- Michael Ignatieff, addressing Stanford University in 2012


"Don't let anyone think for you; most people can barely think for themselves."
-
Rare Earth, ending credits
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RE: Forests and carbon capture
#2
I know tropical forests are absolutely terrible for carbon fixing. Between the high temperatures and humidity any detritus rots completely, building up no soil and fixing no carbon long term.

You want to fix carbon long term? Your best bets are temperate forests, marshes and peat bogs. Anything that builds up soil.

Or... if you are willing to put some work into it? Chop down a good chunk of the taiga forest belts. Charcoal it and then pulverize it to a powder. Dig an absolutely humongous hole as deep as possible. Drop in all the charcoal powder until the hole's only a 100 meters deep, then plug it. The weight of the powder and its small size will handle most of the tamping down of the charcoal for maximum density and minimum volume.

Now just let the forests regrow. It'll take about 100 years and fix carbon down.

You can also do this with other forests. What you want is maximum weight of wood growth for whatever trees you chop, as that would get the most carbon out of the atmosphere.
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RE: Forests and carbon capture
#3
(02-12-2019, 08:40 AM)robkelk Wrote: Remember how I keep telling people to check the numbers, get the facts, and don't listen to people who have a vested interest in getting you to think their way?

Well, here's a worked example of that approach.

Canada's forests actually emit more carbon than they absorb — despite what you've heard on Facebook

Which is simple logic, after all. The carbon that a tree takes into itself while it's growing gets released when it dies and decomposes - and (thanks to wildfires and insect infestations) there have been a lot more trees dying than being planted in the last couple of decades.

Does anybody have relevant statistics for other forests?

If you want to use trees to sequester carbon, you have to keep them from decomposing after they die. Build buildings out of wood, Buy and use wooden furniture. Buy books instead of using the Internet for everything - and keep the books (preferably on wooden bookshelves). And so on.

I think I read something similar in my one of the Science of Discworld book.
If someone tells you that a thing you do causes harm, maybe take a second to think about that rather than jumping right into defending your right to keep doing the thing?

Particularly if the harm discussed includes contributing to a rise in hate crimes or other oppression?

—Rabbi Danya Ruttenberg
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RE: Forests and carbon capture
#4
(02-12-2019, 10:57 AM)hazard Wrote: I know tropical forests are absolutely terrible for carbon fixing. Between the high temperatures and humidity any detritus rots completely, building up no soil and fixing no carbon long term.

You want to fix carbon long term? Your best bets are temperate forests, marshes and peat bogs. Anything that builds up soil.

Or... if you are willing to put some work into it? Chop down a good chunk of the taiga forest belts. Charcoal it and then pulverize it to a powder. Dig an absolutely humongous hole as deep as possible. Drop in all the charcoal powder until the hole's only a 100 meters deep, then plug it. The weight of the powder and its small size will handle most of the tamping down of the charcoal for maximum density and minimum volume.

Now just let the forests regrow. It'll take about 100 years and fix carbon down.

You can also do this with other forests. What you want is maximum weight of wood growth for whatever trees you chop, as that would get the most carbon out of the atmosphere.

Actually, that charcoal powder of yours can probably be used as an ingredient for cement. I know that right now they use powdered coal to do the job - at the cement plant I worked at, there was a coal bunker and a machine to pulverise it and add that to the cement mixture after it had been through the kiln.
Yasuri Nanami is my number one waifu, if only because she would horribly murder all the others if they didn't shut up and toe the line.
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RE: Forests and carbon capture
#5
Cement and concrete are major sources of CO₂ emissions, and will continue to release carbon dioxide for hundreds of years after solidifying.

The terrestrial biosphere only looks like a good place to store carbon because it's so variable. But I'm pretty sure it's nowhere near enough to deal with climate change. The oceans are the key to this, with ocean acidification and the carbonate compensation depth being the major player. If you could get the CO₂ low enough to start dissolving rock instead of living coral, then you buffer the oceans and effectively remove the CO₂. This happens naturally, but on a time scale of 500+ years.

We're running out of time for solutions that don't look like massive geoengineering.
--∇×v⃑
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RE: Forests and carbon capture
#6
It isn't enough. Not on its own.

The big clue though?

It has to remove carbon from the atmosphere and keep it removed. And frankly? We actually know a way to make that happen, we can influence and requires a relatively small investment. What do you think fossil fuel is in the first place?

It's just, we have to structurally remove the net increase in atmospheric carbon, and that's the work of decades no matter what we use. Clear cutting vast swaths of forest to remove already stored carbon and move it to a long term storage facility that is not as vulnerable to a fire and gives room for new, fresh growth to suck down as much CO2 from the atmosphere as possible. After all, young forests have a much greater effect than mature forests, which are effectively negligible at best on the world carbon balance.

Of course, we could also seed the upper layers of the ocean with phosphates and other fertilizers in the hope of creating vast algae blooms that will die off and leave as much detritus raining down to the anoxic ocean floor for burial as possible, but that's even less effective for the amount of effort we'd need to put in.

Of course, elemental carbon (so basically charcoal, remainder is a rounding error) is about 2.2 kg per liter. That's about 2.2 gigatons per cubic kilometer, or billion cubic meters. Historically, there's about 2200 gigatons of CO2 in the planetary atmosphere, and we've added about 1000 (rounding error etc. Source.) which is the amount we need to remove to get to pre industrial era carbondioxide levels. According to the source we can divide this by 3.67 to get the actual amount of carbon we need to store, which is about 272 Gtons. At 2.2 gigatons per cubic kilometer that's approximately 124 cubic kilometers of powdered charcoal we'd need to bury. Or nearly 30 cubic miles for the metrically challenged.

And given that wood is approximately equal to the density of water, that means we need to process nearly 600 gigatons for that. This is actually vaguely plausible; according to wikipedia in 1991 about 3.5 billion cubic meters, equivalent to about 3.5 gigatons, were harvested for various purposes. Of course, total time for this alone to complete sequestering of carbon is some 170 years. And that's not counting the energy cost (and thus CO2 production) of performing this action in the first place.
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RE: Forests and carbon capture
#7
Yeah that's not what I was proposing. I was proposing to dissolve millions of tons of carbonate rocks. Add carbon into the ocean in order to remove it from the atmosphere. This is a chemical equlibrium, the only problem is that the acidic water is on the top of the ocean, and the carbonate rocks are at the bottom. It's a process that's already working to remove massive amounts of carbon dioxide from the atmosphere -- consider how very little ocean pH has changed. Just not quite fast enough.
--∇×v⃑
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RE: Forests and carbon capture
#8
Dissolving carbonate rocks would not tie down more carbon. Quite likely it would do the exact opposite.
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RE: Forests and carbon capture
#9
Really, I believe that intelligent, well planned-out forestry is the answer to a lot of our problems.  It provides us with tried and true building materials as well as materials for making fine furniture (as well as the cheaper varieties).

And this is to say nothing of the jobs it generates - many of which do not require any more education than a High School Diploma provides.  (Forestry is, indeed, one of those fields where people start out as ground-level laborers and, through off- and on-the-job training, pretty much level up to become equipment operators, foremen, and site managers.)

When I was young, Weyerhaeuser pretty much had the market cornered in Washington State.  As early as the early 90's, they'd switched from just clearcutting to actually farming entire swaths of the forests surrounding the Cascade and Olympic mountains, and they've profited greatly from the practice.

Old growth forests do need to be protected, for for no other reason that it provides homes for niche wildlife.  But the practice of farming lumber has far more benefits.
Yasuri Nanami is my number one waifu, if only because she would horribly murder all the others if they didn't shut up and toe the line.
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RE: Forests and carbon capture
#10
Black? There's no way that construction and furniture lumber isn't going back into the atmosphere sooner or later. You need something that will permanently lock down that carbon, inaccessible to oxygen. And that basically means burial, or sinking it into the ocean.
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RE: Forests and carbon capture
#11
the problem being caused by how much of it has been dug or pumped out of the ground and released in the first place, I'm not sure you could really call that a permanent solution either... and finding a way to do it that doesn't end up counterproductive due to energy costs would be a trick, even if finding the political will to carry through would be harder still. No one is going to get reelected spending millions or billions on a plan that won't have any measurable positive effects for decades if not centuries, when their opponent can run on a platform of cutting the expense and cite the conservative party line about there being no solid evidence for human-caused climate change in the first place and then give a sound bite about how for years the liberals have been saying it's bad and now they're trying to do it on purpose. If it's more than half a term away, it doesn't exist in politics.
--
‎noli esse culus
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RE: Forests and carbon capture
#12
Pity it's not feasible to simply launch it into space. All the current solutions have the single weak point that you're trying to sequester the carbon from the biosphere while it's still in the biosphere. Get it off-world with the right trajectory and it's unlikely to ever return to the atmosphere.
-- Bob

I have been Roland, Beowulf, Achilles, Gilgamesh, Clark Kent, Mary Sue, DJ Croft, Skysaber.  I have been 
called a hundred names and will be called a thousand more before the sun grows dim and cold....

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RE: Forests and carbon capture
#13
(02-13-2019, 12:34 AM)hazard Wrote: Dissolving carbonate rocks would not tie down more carbon. Quite likely it would do the exact opposite.

ITT: people casually dismissing opinions offered by experts to offer solutions that don't address the scope of the problem.
--∇×v⃑
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RE: Forests and carbon capture
#14
The problem with dissolving carbonate rocks is that you now have carbonate floating freely through the ocean. Which, when exposed to acidic solutions forms carbonic acid (H2CO3), which dissociates into water and carbondioxide. The net result is just... no improvement. Unless you can link an article explaining it?

And I don't think there are solutions that address the scope of the problem in any time frame shorter than 'decades at minimum, centuries are more likely.'
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RE: Forests and carbon capture
#15
(02-14-2019, 07:48 AM)hazard Wrote: I don't think there are solutions that address the scope of the problem in any time frame shorter than 'decades at minimum, centuries are more likely.'

Hence why we're fucked, and one of several reasons I plan to never have children to be caught up as the world spirals down the drain.
--
‎noli esse culus
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RE: Forests and carbon capture
#16
* Black Aeronaut shrugs.

I did suggest forestry. I will admit that it's not a PERMANENT solution, it will get a good deal of carbon out of circulation for at least a few decades, if not a century or two. And that can buy us the time we need for a more permanent solution....

....Or at least to brace for the inevitable and accept the consequences with at least some grace.

Be pretty interesting to see, I think. Wonder if people were forced to accept that sea levels would rise, how they'll go about dealing with the cities that will be left behind. Will they demolish them? Or leave them to stand as a fascinating sort of at-sea monument?
Yasuri Nanami is my number one waifu, if only because she would horribly murder all the others if they didn't shut up and toe the line.
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RE: Forests and carbon capture
#17
(02-15-2019, 03:30 AM)Black Aeronaut Wrote: * Black Aeronaut shrugs.

I did suggest forestry.  I will admit that it's not a PERMANENT solution, it will get a good deal of carbon out of circulation for at least a few decades, if not a century or two.  And that can buy us the time we need for a more permanent solution....

....Or at least to brace for the inevitable and accept the consequences with at least some grace.

Be pretty interesting to see, I think.  Wonder if people were forced to accept that sea levels would rise, how they'll go about dealing with the cities that will be left behind.  Will they demolish them?  Or leave them to stand as a fascinating sort of at-sea monument?

My vote is for fascinating sort of at-sea monument.  Earlier in the chapter, you see some people changing the street lamps, so that even though the city is submerged, it shines on the water.
--∇×v⃑
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RE: Forests and carbon capture
#18
Black, it will only keep that out of the atmosphere for as long as that forest exists, and the effect will be... highly limited. You'd need to convert vast tracts of land into forests, competing greatly with food production which also needs that fertile soil.
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RE: Forests and carbon capture
#19
Are you saying that lumber doesn't lock carbon down in its various molecular structures?  I'd find that kinda hard to believe.

A quick Google turned this up: https://www.paperonweb.com/A1110.htm

So, we can say roughly about 1.7kg of CO2 per kg of lumber on average.

Page 2 of this report (https://www.fpl.fs.fed.us/documnts/fplrp...lrp615.pdf) states...

Quote:An estimated 48.0 billion board feet (× 10^9 bf) of lumber (softwoods plus hardwoods) was produced in the United States in 2002 (Table 28). This is consistent with near record high production levels since 1999, but about 1.5 × 10^9 bf below the record high production of 49.5 × 109 bf in 1999 (Table 28, Fig. 4).

And to further clarify on the following page...

Quote:Softwood lumber production in 2002 was about 36.4 ×10^9 bf (Table 28, Fig. 4), 76% of total lumber production. Hardwood lumber production was about 11.5 ×10^9 bf.

It also, quite handily, provides the volume-to-weight conversion factors:

Softwood 1,000 board feet = 0.974 Short Tons
Hardwood 1,000 board feet = 1.680 Short Tons

One Short Ton = 907.185 kg

Softwood lumber production was 32,162,974,000 kg in 2002.
Hardwood lumber production was 17,526,814,000 kg in 2002.

Using the above figure of 1.7 kg of CO2 per kg of lumber, that gives us 54,709,899,800 kg, or about 54.7 million metric tons, or about 54,710 kilotons, of sequestered CO2.

In the United States alone.

Wikipedia states that the USA produced 5,172,336 kt of CO2 from fossil fuel emissions in 2015.  (https://en.wikipedia.org/wiki/List_of_co..._emissions)


Unfortunately, I'm a bit pressed for time right now so I have no idea where to find a proper inventory of natural CO2 sources, so if someone else can work that out...

Typically, a forestry company will let a crop go for about 20 years before harvesting, so if we can cut down on CO2 emissions ASAP, stick to using wood as much as possible in construction, then we MIGHT have a shot at this - at least in staving off the worse until we can figure out a more permanent solution.
Yasuri Nanami is my number one waifu, if only because she would horribly murder all the others if they didn't shut up and toe the line.
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RE: Forests and carbon capture
#20
Of course wood consumes carbon to grow - hazard has just been saying that that carbon is released again when the wood rots or is burned, so it's a relatively temporary solution.Even used structurally it's a rare board that won't be replaced within a century or so.
--
‎noli esse culus
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RE: Forests and carbon capture
#21
Even one year is a long time where technological development is concerned these days. For all we know, in fifty years we could be sequestering carbon by the kiloton to build space ships to make the Earth-Mars run.
Yasuri Nanami is my number one waifu, if only because she would horribly murder all the others if they didn't shut up and toe the line.
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RE: Forests and carbon capture
#22
There are many things I could say to that, but I'll hold it to being skeptical of amazing new technology solving any problem until it's shown to be effective and economically viable, whether it's atmospheric carbon dioxide levels, traffic congestion, or the border between Ireland and Northern Ireland post-Brexit. As for space exploration... never mind me, I'll just be over here huddled in despair.
--
‎noli esse culus
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RE: Forests and carbon capture
#23
(02-15-2019, 04:44 PM)Black Aeronaut Wrote: Even one year is a long time where technological development is concerned these days. For all we know, in fifty years we could be sequestering carbon by the kiloton to build space ships to make the Earth-Mars run.

I'm with Classicdrogn. Do not rely on 'amazing new technology' until it's been developed to the point that the proposed technology can be implemented on the scale required to have the effect desired.

Work with the available knowledge and implementable technology. There's a reason I proposed sequestering carbon by producing vast quantities of charcoal and shoving it into a deep hole. A good chunk of all construction lumber is not used for new construction but for maintenance or replacement of existing structures. Which effectively means no net gain in sequestered carbon.


As for the idea of sequestering kilotons of carbon per run by Earth-Mars interplanetary travel?

We need to sequester gigatons. Literally a million times as much as a single run. And I don't see Earth-Mars planetary travel becoming so casual that we're sending a million runs in any appreciable amount of time.
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RE: Forests and carbon capture
#24
And we don't want to put the carbon from the liftoff fuel back into the biosphere, either.
--
Rob Kelk

"Governments have no right to question the loyalty of those who oppose them. Adversaries remain citizens of the same state, common subjects of the same sovereign, servants of the same law."
- Michael Ignatieff, addressing Stanford University in 2012


"Don't let anyone think for you; most people can barely think for themselves."
-
Rare Earth, ending credits
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RE: Forests and carbon capture
#25
I really need to stop reading this thread because you all are making me angry. If I took the time to explain why all of these ideas don't work, or are generally harmful to the biosphere I'd be here all day. I'm an expert in this field, and I don't have any bright ideas either.

But think:
* What ecosystem services are being provided by the element you want to disrupt? Humans are not the only users of land.
* Will your land use change make things worse? Remember, forests absorb more light than farms.
* Do you actually have a plan to collect carbon?
* Does your proposal violate conservation of energy?
* Your climate proposal involving spaceflight does not work, period. You have the atmosphere, the oceans, the biosphere, and the geology to play with, and you need to consider all of them.

If you actually want to do something to make a difference, mostly consider minimizing energy consumption in your life. Don't buy new things so much. Move markets into energy efficient goods by buying them. In California, you can contact your electricity provider and request 100% renewable energy.
--∇×v⃑
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