Lovelock on charcoal: One last chance to save mankind

[GliderGuider]

One last chance to save mankind

Your work on atmospheric chlorofluorocarbons led eventually to a global CFC ban that saved us from ozone-layer depletion. Do we have time to do a similar thing with carbon emissions to save ourselves from climate change?

Not a hope in hell. Most of the "green" stuff is verging on a gigantic scam. Carbon trading, with its huge government subsidies, is just what finance and industry wanted. It's not going to do a damn thing about climate change, but it'll make a lot of money for a lot of people and postpone the moment of reckoning. I am not against renewable energy, but to spoil all the decent countryside in the UK with wind farms is driving me mad. It's absolutely unnecessary, and it takes 2500 square kilometres to produce a gigawatt - that's an awful lot of countryside.

What about work to sequester carbon dioxide?

That is a waste of time. It's a crazy idea - and dangerous. It would take so long and use so much energy that it will not be done.

Do you still advocate nuclear power as a solution to climate change?

It is a way for the UK to solve its energy problems, but it is not a global cure for climate change. It is too late for emissions reduction measures.

So are we doomed?

There is one way we could save ourselves and that is through the massive burial of charcoal. It would mean farmers turning all their agricultural waste - which contains carbon that the plants have spent the summer sequestering - into non-biodegradable charcoal, and burying it in the soil. Then you can start shifting really hefty quantities of carbon out of the system and pull the CO2 down quite fast.

Would it make enough of a difference?

Yes. The biosphere pumps out 550 gigatonnes of carbon yearly; we put in only 30 gigatonnes. Ninety-nine per cent of the carbon that is fixed by plants is released back into the atmosphere within a year or so by consumers like bacteria, nematodes and worms. What we can do is cheat those consumers by getting farmers to burn their crop waste at very low oxygen levels to turn it into charcoal, which the farmer then ploughs into the field. A little CO2 is released but the bulk of it gets converted to carbon. You get a few per cent of biofuel as a by-product of the combustion process, which the farmer can sell. This scheme would need no subsidy: the farmer would make a profit. This is the one thing we can do that will make a difference, but I bet they won't do it.

Do you think we will survive?

I'm an optimistic pessimist. I think it's wrong to assume we'll survive 2 °C of warming: there are already too many people on Earth. At 4 °C we could not survive with even one-tenth of our current population. The reason is we would not find enough food, unless we synthesised it. Because of this, the cull during this century is going to be huge, up to 90 per cent. The number of people remaining at the end of the century will probably be a billion or less. It has happened before: between the ice ages there were bottlenecks when there were only 2000 people left. It's happening again.

I don't think humans react fast enough or are clever enough to handle what's coming up. Kyoto was 11 years ago. Virtually nothing's been done except endless talk and meetings.

And the old bugger is going into space later this year, at age 90. What a remarkable man

[tavalon]

1. He developed Gaian theory, to which I subscribe

He's right about the weird optimism, pessimism. Gaia is very ill, but she won't die as long as we do. Or at least most of us. When I look at my own family, that hurts and scares the fuck out of me. When I look at it from a global point, I think it's clear she needs to dust off some of the parasites. I would love to anthropormorphise Gaia and say she will pick the best and the brightest but no such luck. She is living, but i doubt she sees us as her nervous system, (the eyes of Gaia. I think that might just be our hubris).

It would be nice if we could pull a solution out of our collective asses and goodness knows, there have been some amazing saves in the past, but we don't really think this big. We're still pretty tribal. Which is why, after the life shock, a billion people scattered in caves, trying to learn new ways might not be so bad - in the long term, of course.

Short term, Mr. Lovelock won't be around to see the end game, but he's seen more than he thought he would and it sucks.

[OKIsItJustMe]

2. I like Lovelock, and his Gaia Hypothesis

but I had gotten the distinct impression that neither were popular on this board.

[GliderGuider]

4. "Don't anthropomorphize your planet...

...it hates that!"

I think of "Gaia" simply as a large complex adaptive system. Attributing intentionality to the planet and its biosphere is unnecessary to explain its behaviour (and despite our preening, much the same can be said about humanity).

Lovelock is unpopular because he sees no opportunity for the triumph of human will. To a lot of people that position seems repugnant and defeatist, though I think that's just evidence of a psychological barrier on the part of the objectors, easily cured by a minor shift in philosophical perspective.

[OKIsItJustMe]

7. I don't believe the true "Gaia Hypothesis" attributes intentionality

It simply says you can find analogues within the ecosystem to all of the systems in an organism. I found that http://www.amazon.com/Gaia-New-Look-Life-Earth/dp/0192862189/">in its original form, it was a helpful way of thinking about ecosystems.

Unfortunately, the "new-agers" grabbed hold of it, and a useful analogy became a pseudo-religion.

[GliderGuider]

9. That's true. Unfortunately the popularization of the idea has distorted it.

The concept of the planet as a "conscious" entity is a very powerful, behaviour-altering metaphor. however, unsophisticated people tend to reify the meme.

[OKIsItJustMe]

13. "Lovelock is unpopular because he sees no opportunity for the triumph of human will."

Actually, check this out from the interview:

… For the first time in its 3.5 billion years of existence, the planet has an intelligent, communicating species that can consider the whole system and even do things about it. They are not yet bright enough, they have still to evolve quite a way, but they could become a very positive contributor to planetary welfare.

…

On the whole, I see this as an optimistic viewpoint.

[GliderGuider]

15. It's a pretty guarded optimism

"Not yet bright enough" ... "could become" ... it's not exactly a ringing endorsement of human capabilities.

I wonder how much evolutionary psychology Lovelock knows? Learning a bit about it was what finally painted the window shut for me. When I understood that for all our intelligence we are not and cannot ever be fully rational because of our brain structure, I became totally skeptical of the technocratic agenda.

[OKIsItJustMe]

19. Actually, "fully rational" may not be all it's cracked up to be

Check out this recent episode of Radiolab:
http://www.wnyc.org/shows/radiolab/episodes/2008/11/14

…

Overcome By Emotion

Instinct or analysis? Wouldn't things be easier if we could get emotion out of the way and let rational analysis lead? Except that so often, that gut feeling turns out to be right. We explore both extremes. Antoine Bechara, a psychology professor at USC, tells us about the case of Elliot, an accountant who, after having a tumor removed from his brain, became entirely rational. And writer Steven Johnson recounts the powerful grip emotion held over his brain in the years following a frightening event. …

I'm fascinated by the work of http://en.wikipedia.org/wiki/Mark_Tilden">Mark Tilden and http://en.wikipedia.org/wiki/BEAM_robotics">BEAM robotics. His breakthrough in creating robots was the use of simple analog control circuits, rather than complex logic circuits.

When you pair the two, phenomenal things become possible.

[jpak]

5. Gaia is not popular in the scientific community because it has no evidence to support it.

and Lovelock has done everything he could to alienate his critics and supporters.

He despises not only *real* scientists but environmentalists as well.

[GliderGuider]

8. Do you understand why he despises environmentalists?

He's hardly alone in that. I agree with him that most environmentalists are blinkered, anthropocentric fools. By refusing to abandon a world-view that has humanity at its center they end up promoting little more than a slower, more controlled, more "humane" destruction of the rest of life on the planet.

[LiberalEsto]

3. Charcoal burial is a great idea

I've read about the super-fertile terra preta soils in the Amazon basin, which contain vast amounts of human-made charcoal. Here are links with a lot of information about it:

http://www.biochar.org/joomla/

http://www.popularmechanics.com/science/research/4297513.html

[GliderGuider]

6. I agree.

Burying charcoal is the only carbon sequestration idea I favour. That's because it can address three problems simultaneously: along with carbon sequestration it could provide a minor source of energy, and it may improve soil fertility without the use of NG-derived fertilizers. When you consider that it's low-tech and can be done at any scale from backyard to industrial, biochar really starts to look like a winner.

[HamdenRice]

10. Charcoal burial is not a good idea

It may play some role, but not a very big one. There are cheaper, easier, less environmentally destructive forms of using nature to sequester carbon. But his overall point about the scale of the natural carbon cycle and our activities is important. Change the natural cycle a little and our contribution becomes manageable.

The most immediate way to sequester carbon is simple reforestation. Making charcoal produces a host of other very toxic hydro carbons and other gasses to sequester a portion of the carbon. It's better to leave that plant material in tact -- as a standing forest. So much of the world's forests have been cut already that reforestation is much cleaner and faster. Only after the forests have been fully restored and reached equillibrium might we consider cutting sequestering that carbon as charcoal. Even then it seems counter productive, because we could simply bury the wood in mine shafts and the like without burning it.

If you think making charcoal on a massive scale is a good thing, you should have been in Singapore in 1998 with me, when far away Indonesian slash and burn caused massive pollution across thousands of miles of southeast Asia.

The scale of vegetation burning that would be required to affect warming would be devastating. It's a bad and environmentally dirty idea.

[OKIsItJustMe]

11. "It's better to leave that plant material in tact (sic) -- as a standing forest."

Please note, Lovelock was not advocating burning trees (as some have.) Instead, he is advocating turning "agricultural waste" into charcoal.

[HamdenRice]

12. Yes, but the burning of so much agri waste would be catastrophic

Also, growing and burning of wood charcoal has been advocated on this forum in the past.

[OKIsItJustMe]

14. "growing and burning of wood charcoal has been advocated on this forum in the past."

Yes it has, and I think I mounted a decent argument against it. It's intellectually dishonest to criticize Lovelock's proposal, by saying, that others have recommended burning forests.

Here's what Lovelock suggested:

…

There is one way we could save ourselves and that is through the massive burial of charcoal. It would mean farmers turning all their agricultural waste - which contains carbon that the plants have spent the summer sequestering - into non-biodegradable charcoal, and burying it in the soil. Then you can start shifting really hefty quantities of carbon out of the system and pull the CO₂ down quite fast.

Would it make enough of a difference?

Yes. The biosphere pumps out 550 gigatonnes of carbon yearly; we put in only 30 gigatonnes. Ninety-nine per cent of the carbon that is fixed by plants is released back into the atmosphere within a year or so by consumers like bacteria, nematodes and worms. What we can do is cheat those consumers by getting farmers to burn their crop waste at very low oxygen levels to turn it into charcoal, which the farmer then ploughs into the field. A little CO₂ is released but the bulk of it gets converted to carbon. You get a few per cent of biofuel as a by-product of the combustion process, which the farmer can sell. This scheme would need no subsidy: the farmer would make a profit. This is the one thing we can do that will make a difference, but I bet they won't do it.

…

It's actually a pretty reasonable idea in my opinion. "Biochar," using agricultural waste, could actually help address the problem of deforestation.

http://en.wikipedia.org/wiki/Biochar#Background

…

In specific locations - e.g. at the tropical forest frontier in Central Africa amongst ultra-poor communities of slash-and-burn farmers - biochar may become the kernel of a highly integrated sustainable development and poverty alleviation concept that can tackle key issues simultaneously: hunger and food insecurity, low agricultural productivity and soil depletion, deforestation and biodiversity loss, energy poverty (and related health problems such as indoor air pollution), and climate change. In this concept, multiple carbon reductions would come from the char in the soil (carbon sink), the avoided deforestation and its associated emissions, and the emissions avoided by making a switch from cooking with unsustainably harvested fuel wood on inefficient open fires to more efficient biochar-generating, small-scale energy production.

…

Switching from slash-and-burn to slash-and-char techniques in Brazil can both decrease deforestation of the Amazon and increase the crop yield. Under the current method of slash-and-burn, only 3% of the carbon from the organic material is left in the soil.

Switching to slash-and-char can sequester up to 50% of the carbon in a highly stable form. Adding the biochar back into the soil rather than removing it all for energy production is necessary to avoid heavy increases in the cost and emissions from more required nitrogen fertilizers. Additionally, by improving the soil tilth, fertility, and productivity, the biochar enhanced soils can sustain agricultural production, whereas non-amended soils quickly become depleted of nutrients, and the fields are abandoned, leading to a continuous slash-and-burn cycle and the continued loss of tropical rainforest. Using pyrolysis to produce bio-energy also has the added benefit of not requiring infrastructure changes the way processing biomass for cellulosic ethanol does. Additionally, the biochar produced can be applied by the currently used tillage machinery or equipment used to apply fertilizer.

…

[HamdenRice]

16. Lovelock isn't here. I was addressing forum members not Lovelock

so it's puzzling how addressing forum members and the things they have advocated is intellectually dishonest.

Even slash and char is bad for the air quality. Did you look at the pictures in the bio char link? Would you really want a billion or two billion farmers world wide to have chocking, belching, smoking charcoal piles burning their crop residues and nearby "secondary forest" in "low oxygen" fires?



Have you ever seen a charcoal pit or oven in the third world? Can you see why the guys who work in them usually have wet teeshirts tied around their noses and mouths?

There's a reason that in most jurisdictions in the U.S., burning leaves in the fall has been outlawed. It creates a toxic, choking mess.

Having the farmers of the world switch to burning their crop residues might sequester a little carbon (less than reforestation), but would lead to catastrophic air pollution.

[GliderGuider]

17. Burning straw men creates much smoke, but little light.

Comparing charcoal-making in a modern retort to third world charcoal heaps is a straw man. Even a single-user retort produces little smoke compared an open pit:



http://www.biocoal.org/3.html">This article describes a low-cost charcoal retort suitable for third-world countries, with low levels of smoke, high efficiency and low cost:

The plant is called ICPS (Improved Charcoal Production System) or "adam-retort" and has the following advantages:

* Economical, with an efficiency of approx. 35% to 45% instead of about 18% efficiency compared to the traditional systems (calculated from dry weight of wood).

* Recycling and clean combustion of the pyrolysis gas during the 2nd phase of operation (‘retort-system’) results in a low-emission of carbon monoxides during the charcoal production. The effective carbonisation of the biomass takes only about 10 hours.

* Low investment costs (about ~500 Euros for materials and work) and a simple construction with locally available materials.

* A volume of approx. 3m³ of biomass (corresponding to approx. 600 to 900kg wood, coconut shells, etc., dry weight- water not counted) can be converted to up to 350kg of charcoal.

* An effective 24-30 hour production cycle (known as a ‘batch’) and a simple operation of the plant result in an increased income for its operators. The right system to be used in rural areas or semi-industrial production like at forest projects, energy-wood plantations and charcoal makers.

* Only waste and residual biomass needs to be burnt (~50kg) in a separate fire box to dry and heat the wood and initiate the carbonisation process during the 1st phase.

* The concept of the ICPS / “adam-retort” is that the retort works in 2 stages – the first and the second phase. In the first phase the wood in the retort chamber is dried by hot flue gases and the carbonisation is initiated. The hot flue gases are produced with cheap waste wood in an external fire chamber. By waste wood we understand branches, crust, charcoal dust and other residual products from agricultural processes, such as coffee husks. About 50 kg of waste wood is burned per batch.

During traditional charcoal production a part of the ‘good’ wood must be burned down in order to carbonise the rest of the wood.

As soon as the water in the wood has evaporated, the smoke is sufficiently hot and the first inflammable wood gases appear, the smoke is now rerouted and burnt in the hot fire chamber, reducing pollution. This additional energy is used to heat up the wood chamber and to further accelerate carbonisation during this second phase

In the traditional carbonisation process, the smoke clouds remain in the air for 4 – 14 days. The smoke created by the “adam-retort” carbonises within approximately 10 hours with some of the smoke being burnt off in a fire box. If the carbonisation begins in the morning, the retort-kiln can be closed by the evening. The charcoal cools overnight by a special cooling method. By the next morning, the charcoal is ready to use.

The plant can be built for approximately ~500 Euro in coutries with low labour costs.

[HamdenRice]

26. "Only" 500 euros? In countries where people live on a dollar or two a day?

And where is this 500 euros going to come from? And why would a farmer buy it when he can dig a charcoal pit for free?

This is so illogical, I don't know where to begin. And just what do you think burning in "low oxygen" environment means -- and that's the only way to make charcoal, burning in low oxygen. It means carbon monoxide, nitrogenous gases and a lot of stuff that makes CO2 look like clean air. And if we're talking about crop residue, it means burning off the nitrogen as gas rather than returning it to the soil, which means more fossil fertilizer is needed.

Plus this keeps going back and forth between wood and crop residue. Your link is to a kiln for making wood charcoal (ie by small scale charcoal producers, not farmers), something you refer to even in your own excerpt. That kiln if fine as an improvement for making wood charcoal for cooking. It is not a way to dispose of crop residue in the soil. If we are talking about wood charcoal for carbon sequestration, then once again, it's better, less polluting, more efficient and sequesters more carbon to leave it as wood. If we're talking about crop residue, that requires a different process.

[GliderGuider]

35. What part of "other residual products from agricultural processes" did you not read?

500 Euros for a plant that can produce a tonne of charcoal a week seems like a good investment for a village. Heck, the amount is small enough to be capitalized by a loan from kiva.org, and many such loans are being given out to the third-world poor.

Especially in a country that has a tradition of charcoal use, and especially a tradition of earth-mount charcoal production, such retorts would be a godsend for improving air quality.

So: it's cheap, it's applicable to both first and third world nations, it can be used for agricultural waste, wood scraps or purpose-grown wood, and it permits much of the carbon in the raw biomass to be stabilized for sequestration.

Oh, and regarding waste gases: CO oxidizes rapidly into CO2 when it's in the open air, so it's not a big issue. A modern retort (not the adam-retort mentioned above) can even capture these gases and turn them into methane.

I still don't understand what's at the core of your objection, because none of the arguments you've raised so far seem to be significant. Can you clarify your concerns a bit?

[HamdenRice]

39. My objection is you're not making any sense at all

The site you linked to is a site about kilns for making charcoal from wood. I have nothing against better kilns for rural areas that rely on charcoal. But that's not about charcoal sequestration through burning crop residue.

If you want to sequester carbon and we're talking about wood (not crop residue), then reforestation is much, much better and less polluting.

If we're talking about sequestering carbon by burning crop residue, then we're not talking about kilns, we're talking about fires that produce horrendous pollution. (See Wisconsin link below.)

It fails the cost benefit analysis miserably.

If, by some bizarre leap of faith, you're talking about a kiln for crop residue (and I don't know of any such invention), then how will villagers haul their crop residue, spread over hundreds of acres, to the kiln -- with a diesel tractor? Why would they do that when for most cultures, green manuring (ie in place composting) already works well for them. What's in it to them to lose their nitrogenous fertilizer to sequester carbon, while choking their children in noxious fumes?

You simply haven't described an economically or ecologically logical system. It simply makes no sense.

[OKIsItJustMe]

18. Charcoal burning releases carbon dioxide immediately, and in a concentrated form

Letting the waste degrade in the usual way releases CO₂ in a diffuse manner, over a longer period of time, and over a larger geographic area.

The result of the charcoal burner is much more obvious. However, the idea here is that in net, less carbon will be released into the atmosphere.

If you think about it for a moment, this should be obvious. After all, creating charcoal and burying it clearly results in more carbon (the charcoal) winding up in the soil.

Lovelock's proposal is quite importantly different from the proposal to plant and burn forests. That's why I say it is intellectually dishonest, to criticize Lovelock's proposal based on proposals made by others.

[GliderGuider]

20. The only concern I have with Lovelock's proposal

Is over the removal of that much organic material from agricultural soil. I've heard permaculturists say "there is no such thing as agricultural waste". It should be possible to remediate some of the loss by tilling in the char, but I'd want to see some careful studies before we tried it on a large scale.

At the moment I prefer the coppice willow/poplar or bamboo approach, where fast-growing trees are grown on land that would otherwise be re-forested. The biomass is harvested every few years, charred, the char returned to the soil where the trees were grown, and replacement trees planted. This provides for the continuous growth of trees, and continuous sequestration of carbon -- unlike simple reforestation that provides only a single growth cycle of carbon uptake.

[OKIsItJustMe]

22. Here's the mitigating factor (in my mind)

If you can successfully transition from slash-and-burn to slash-and-char, there are obvious benefits.

However, yes, any time you're taking nutrients out of the soil, and not replacing them, there will clearly be a depletion over time.

[kristopher]

21. Where is the logic in that?

You compare BURYING charred boimass with UNBURIED raw biomass and then claim the significant variable re total carbon release is charred/uncharred?

Bury the uncharred biomass and it won't release any CO2.

Plowing under isn't burying. You are talking about the biomass being distributed throughout the top few inches of soil.

[GliderGuider]

23. Charring is what allows it to be effictive if it's simply plowed in.

Yes, you need exclude oxygen from raw biomass in order for it to retain its carbon. Char is much less susceptible to spontaneous oxidation. That makes char a decent soil amendment for agriculture without losing its attractiveness as carbon sequestration.

[OKIsItJustMe]

24. Please re-read

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=184019&mesg_id=184062

… Ninety-nine per cent of the carbon that is fixed by plants is released back into the atmosphere within a year or so by consumers like bacteria, nematodes and worms. …

[kristopher]

25. There is nothing to reread

And your ceaseless tap dancing to avoid owning up to errors is getting old.

You made an invalid comparison. Actually two of them. Lovelock is advocating farmers worldwide char and plow under, presumably because BURYING isn't as practical for them. Yet the argument is being made that using specialized equipment for burning vs just covering with dirt IS feasible...

The entire discussion is muddled, so say the least.

[HamdenRice]

27. I agree. It's become completely illogical and somewhat circular nt

[OKIsItJustMe]

29. somewhat circular

Absolutely, since I repeat those things which have already been stated, and you simply choose to ignore.

[HamdenRice]

31. See post below nt

[OKIsItJustMe]

28. I don't follow you at all

However, apparently, you've made no attempt to follow me. So, I guess we're even.

Lovelock's claim, is that the sort of creature you find under the ground (i.e. "bacteria, http://en.wikipedia.org/wiki/Nematode">nematodes and http://en.wikipedia.org/wiki/Worm">worms") which normally decompose plant matter, will release 99% the carbon buried in the form of plants within a year or so.

The idea is that the charcoal is much more stable:
http://en.wikipedia.org/wiki/Biochar#Pyrolysis_of_biomass_as_a_carbon_sink

…

Biochar can be used to sequester carbon on centurial or even millennial time scales. Plant matter absorbs CO₂ from the atmosphere while growing. In the natural carbon cycle, plant matter decomposes rapidly after the plant dies, which emits CO₂; the overall natural cycle is carbon neutral. Instead of allowing the plant matter to decompose, pyrolysis can be used to sequester the carbon in a much more stable form. Biochar thus removes circulating CO₂ from the atmosphere and stores it in virtually permanent soil carbon pools, making it a carbon-negative process. …

Do you have evidence to contradict this claim?

[HamdenRice]

30. What are the byproducts of producing char? That's the question

No one is disputing that some amount of carbon can be sequestered this way. The question is the environmental cost and whether it's the best way.

Composting, including plowing under, does indeed release almost all carbon back in the atmosphere. But it is extremely, extremely efficient. From the worm that eats the leaf, to the bacteria in the worm's gut, to the mold that eats the worm feces, to the next thing that eats the mold, every step down in energy is extremely efficient. All that's generally produced is CO2 and water. If there are anaerobic phases, you might get CO2 and alcohol or methane, but generally it's super efficient, because every creature in the chain has evolved efficiently.

If you want to make charcoal, you have to burn that crop residue in a low oxygen environment. If you burn it in a high oxygen environment, you won't get charcoal. So you have to burn it in a low oxygen environment.

A low oxygen fire is extremely polluting. You get lots of toxic substances that are arguably worse than the CO2 of biological decomposition. You don't even sequester all the carbon, because most of the hydro carbons in the plant material are burned to create the heat to turn the remainder into carbon. I notice that no one has provided a figure for what percentage of carbon in a a typical plant crop residue once turned to charcoal has been sequestered, and what percentage released as carbon monoxide, carbon dioxide and other nasty things. Is it 50%? Is it 10%?

So it's not a very good way of sequestering carbon. As kristopher is pointing out, if you wanted farmers worldwide to sequester the carbon of their crop residues, a better way would be to dig a five foot deep trench and bury it. Almost 100% sequestration (or very, very slow release), no smoke, no carbon monoxide etc.

But all this is moot. Farmers are not going to dig trenches to bury their crop residue and they're not going to make charcoal from crop residue. It's a kind of silly idea when you look at the economic burdens this places on farmers for no particular gain.

Creating tera preta may be a very good thing for farmers in certain tropical environments in terms of soil management. But it is not a viable method of carbon sequestration by any logical argument.

Here's a Wisconsin Environmental agency warning against leaf burning and the kinds of pollutants created by low temperature fires. Given the volume of crop residue, I don't see any way to burn it without producing these by products. In fact, I don't see how farmers are supposed to burn crop residue in a low oxygen environment in the first place:

http://dnr.wi.gov/air/aq/burning/leaves.htm

Open burning IS NOT an environmentally sound way to dispose of leaves and plant clippings at your home. State law currently allows people to burn small amounts of dry leaves and brush on their own property so long as leaf burning is not prohibited by local ordinances. However, you should try to avoid burning leaves whenever possible.

The smoke generated by a large number of simultaneous leaf fires can cause significant health problems. Leaf smoke can irritate the eyes, nose and throat of healthy adults. But it can be much more harmful to small children, the elderly, and people with asthma or other lung or heart diseases. This is because the visible smoke from leaf fires is made up almost entirely of tiny particles that can reach deep into lung tissue and cause symptoms such as coughing, wheezing, chest pain and shortness of breath--symptoms that might not occur until several days after exposure to large amounts of leaf smoke.

Besides being an irritant, leaf smoke contains many hazardous chemicals, including carbon monoxide and benzo(a)pyrene. Carbon monoxide binds with hemoglobin in the bloodstream and thus reduces the amount of oxygen in the blood and lungs. So carbon monoxide can be very dangerous for young children with immature lungs, smokers, the elderly, and people with chronic heart or lung diseases.

Benzo(a)pyrene is known to cause cancer in animals and is believed to be a major factor in lung cancer caused by cigarette smoke. It is found in cigarette smoke and coal tar as well as leaf smoke.

[OKIsItJustMe]

33. I notice that no one has provided a figure for what percentage of carbon

http://www.democraticunderground.com/discuss/duboard.php?az=show_mesg&forum=115&topic_id=184019&mesg_id=184062

…

Switching from slash-and-burn to slash-and-char techniques in Brazil can both decrease deforestation of the Amazon and increase the crop yield. Under the current method of slash-and-burn, only 3% of the carbon from the organic material is left in the soil.

Switching to slash-and-char can sequester up to 50% of the carbon in a highly stable form. …

[HamdenRice]

34. And the other questions?

So let's say it sequesters 50%. The other 50% is released as carbon monoxide (much more toxic than CO2), complex partly burned hydrocarbons, ash, soot and other particle pollutants, benzenes and nitrogenous toxic gases -- and of course half the CO2 we're supposed to be sequestering.

How are farmers supposed to burn crop residue in low oxygen conditions without creating all the hazards mentioned in the Wisconsin agency site?

Are they all supposed to buy kilns large enough to hold 10, 20 or 50 acres worth of crop residue? And would the kilns be exempt from air pollution standards?

Do you disagree with the fact that there is a reason leaf burning is banned in many jurisdictions across the country?

[OKIsItJustMe]

38. "Do you disagree with the fact that there is a reason leaf burning is banned in many jurisdictions"

I don't disagree. There is a reason.

However, what happens in "slash-and-burn" agriculture? We're talking about moving them away from that.

[HamdenRice]

40. No we're not in terms of pollutants

How exactly does one burn crop residue without creating the pollutants described.

No one has described this, but it's pretty obvious what will be happening: massive amounts of thick, choking, dangerous low oxygen fire smoke.

[OKIsItJustMe]

42. So, you would prefer they continue to burn the forests instead

Is that right? (Clearly it isn't.)

Remember, we're talking about setting up a sustainable system of agriculture, which as a side-benefit also sequesters carbon.

[HamdenRice]

43. Straw man

I didn't say that at all. Let's try to stay on track. We could start a different thread about how to limit slash and burn, based on what I think would help tropical farmers. I could base some of it on my firsthand fieldwork work in China and Africa. But that's not what we are talking about in this thread.

This discussion is about the (to me preposterous) idea of the OP -- that farmers world wide should burn crop residue to sequester carbon.

That means burning billions of tons of crop residue in low oxygen fires. How exactly is that supposed to happen without massive environmental devastation?

Is that the best way to sequester carbon? Is there anything feasible about this?

In short, no.

[OKIsItJustMe]

45. "Is that the best way to sequester carbon? Is there anything feasible about this?"

Fair enough. What is a better, more feasible way to sequester carbon? (Remember, that roughly 1/3 of greenhouse gasses are generated by agriculture, and much of that by "slash and burn.")

http://aphg.jhsph.edu/?event=browse.subject&subjectID=18

[HamdenRice]

46. Reforestation

I realize that this gets me in trouble with the neo-malthusians, but from everything I've seen in the field and everything I've read, I am convinced by the agricultural-economic consensus that agricultural production is extremely elastic. Although it looks like we're constantly gobbling up land to produce more food, more land is only one way to produce more food. There are many, many farming systems in the world, each with its own productivity characteristics.

Most farming today is very land hungry and not very efficient. We could feed the entire planet on probably about 1/2 or less of all land under cultivation today. And the remarkable thing is that because the techniques are well known and farmers are extremely adaptable, reducing the land under cultivation would essentially induce the needed increases in output. Food is produced by land, labor and capital, and the replacement of land with labor would also absorb a lot of third world unemployment and reduce poverty and food insecurity (because when you're on a farm to which you have crop entitlements, even if you're poor, you don't go hungry -- according to Nobel economics laureate Amartya Sen).

Most of the destruction of rain forest in the last 3 decades has been utterly unnecessary. There are millions of acres of former rain forest that could be restored, and that have already been effectively abandoned.

The first step in sequestration is restoring the forests to their former levels. When they reach equillibrium, then we can talk about other forms of sequestation. But simply the growing of the former forests would take billions of tons of CO2 out of the atmosphere. And it doesn't produce ash, smoke, benzene, or other toxic pollutants.

I don't know if that's the entire solution but it's certainly something I would try before burning crop residue.

[OKIsItJustMe]

48. By all means! Reforest!

However, it's been estimated that for the first 5 to 10 years of its life, a newly-planted forest is carbon-negativepositive.

We need something to do right now. One of the first things we can do right now is to stop (or at least slow) deforestation. A mature forest which is never burnt is much better than an immature one.

One of the big reasons for deforestation is that slash-and-burn agriculture depletes the soil of carbon. So, the farmers use up their patch of land, and then burn more forest.
http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6V67-3VM0M2X-1&_user=681878&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000037398&_version=1&_urlVersion=0&_userid=681878&md5=a30ac63ab9b0261c15797f0d99028c1c


Whether you agree that Biochar is an effective way of sequestering carbon or not, if it slows the rate of deforestation, how can you be against it?

[HamdenRice]

50. I'm not against char for soil management

I wrote, upthread:

"Creating tera preta may be a very good thing for farmers in certain tropical environments in terms of soil management. But it is not a viable method of carbon sequestration by any logical argument."

So I agree that in certain tropical environments, creating tera preta is good soil management and leads to a decrease in deforestation.

But it is primarily a soil management technique (and by extension forest protection technique as you point out), but not a carbon sequestration technique.

You wrote that forests are carbon negative for 10-15 years. I'm not sure what you mean, but I assume you mean that the forest absorbs carbon for 10-15 years, after which the decay of old wood reaches equillibrium with new trees. But there are many ways to increase that period of carbon negativity for decades, and manipulate it through succession of species. Most forests in the modern age are second growth "bush forest" that reach equillibrium with invasive species. In the southeast, for example, that's scrub pine. Scrub pine lives for maybe 50 years so it reaches temporary equillibrium and becomes carbon neutral. If the forest were to continue for 1,000 years, however, it would probably revert to an oak/maple/hickory climax forest.

We can, however, speed up that process. If let's say a scrub pine forest is carbon negative for 10 years and levels off, we can selectively cut the pine (and sequester the wood) and plant douglass fir. When the fir reaches equillibrium, we can plant maple/oak/hickory.

In tropical areas, the same could be said for starting with an invasive eucalyptus, and then speeding up the climax forest of mahogany/brazil nut.

So the basic idea is the creation of massive national parks with highly managed forest successions, speeding up the process of reaching climax forests, keeping them carbon negative for a century or more.

[OKIsItJustMe]

54. Yes, I miswrote-immature forests are actually carbon-positive

It's hard for me to think:
Positive = Good
Negative = Bad

The Wikipedia article I cited http://en.wikipedia.org/wiki/Biochar#Background , specifically spoke of "… the tropical forest frontier in Central Africa …"

[kristopher]

32. Yes.

What is the soil depth at which anoxic conditions begin? Without oxygen, isn't it difficult to convert carbon to CO2?

He (and you) are talking about plowing under, not burying.

FWIW a new paper looks at the issue:

For significant impact any method to remove CO2 from the atmosphere must process large amounts of carbon efficiently, be repeatable, sequester carbon for thousands of years, be practical, economical and be implemented soon. The only method that meets these criteria is removal of crop residues and burial in the deep ocean. We show here that this method is 92% efficient in sequestration of crop residue carbon while cellulosic ethanol production is only 32% and soil sequestration is about 14% efficient. Deep ocean sequestration can potentially capture 15% of the current global CO2 annual increase, returning that carbon back to deep sediments, confining the carbon for millennia, while using existing capital infrastructure and technology. Because of these clear advantages, we recommend enhanced research into permanent sequestration of crop residues in the deep ocean.

Note that the term used is "soil sequestration".

[OKIsItJustMe]

36. OK so let me see if I understand you

You believe it is easier for people to dispose of crop wastes in the deep ocean, than it is for them to create biochar.

(Is that right?)

Even if deep ocean disposal was tremendously more effective, what volume of "crop residues" do you think could possibly make it there?

Or, are you saying that it's easier for people to bury crop waste sufficiently deeply in the soil, than to sow charcoal in their fields? (What about where the soil is relatively shallow, as it tends to be in the regions being discussed?)


PS on a personal note, when possible, please cite sources.

[kristopher]

41. See what I mean?

Look at how far you go to avoid admitting an error.

I wrote that "FWIW here is a new study looking at the issue". Nowhere do I endorse the proposal, I just posted the abstract because it quantifies the discussion that was taking place.
Instead of acknowledging what the quantification shows (your error) you constructed a strawman.

You spoke of intellectual integrity earlier, perhaps you should reflect a little on the concept.

The paper isn't yet published but is due out soon in Environmental Science and Technology.

[OKIsItJustMe]

44. OK, treat me like I'm stupid for a minute

Please, briefly and explicitly explain to me the grievous error that I'm supposedly running away from.

[kristopher]

47. It isn't a "grievous error"

That's what makes your tap dancing so silly.

You compared burying charred and uncharred biomass and claimed the difference in sequestration favors char. That is true in cases of plowing the biomass under, but not in cases of "burying". When you bury biomass anoxic conditions are the norm; when you plow it under, anoxia is deliberately discouraged.

Also Hamden Rice has made a completely accurate summation of the pros and cons of the proposal. Your focus on CO2 to the exclusion of all other pollutants as well as your refusal to recognize more effective alternatives are more of the same trait in action.

[OKIsItJustMe]

49. "That is true in cases of plowing the biomass under, but not in cases of 'burying'."

Here's my way of thinking.

It's all very well and good to say, "If they buried the plants that would be better." Or, "If they sunk them in the deep ocean, that would be better still."

OK, so, let's say I grant that for a given unit of plant matter. Furthermore I will grant that creating charcoal also creates undesirable byproducts.

Now, the question is, which is most likely to be done, and in the greatest volume?

First, which is most easily accomplished?

Next, what is the incentive to do it? With the Biochar scheme, there's a potential profit motive. With the burial scheme, there's the satisfaction of knowing you're doing the right thing™.

Which do you think is most likely to be done?

[kristopher]

56. Hamden Rice addressed that line of thought.

plowing raw biomass under is most likely because of the direct benefit/cost calculation of the farmer.

[GliderGuider]

57. Agriculturally, ecologically and economically, it's the most sensible thing to do.

Keep the organic material in the soil where it belongs.

The CO2 we're worried about comes from burning fossil fuels, so it makes sense to address the problem in that arena in which it is created. If we stop burning coal, oil and natural gas and the problem goes away (eventually).

[OKIsItJustMe]

58. "… plowing raw biomass under is most likely …"

However, as you acknowledge, that doesn't do as much for carbon sequestration. Lovelock claims that through producing Biochar:

… You get a few per cent of biofuel as a by-product of the combustion process, which the farmer can sell. …

Given the profit motive, the farmer might be convinced to do it.

[kristopher]

59. And how does burning it for fuel help our CO2 goal?

Your entire argument is that the charred biomass is permanently in that state as a part of the surface soil.


Doesn't something about your total picture strike you as odd?

[GliderGuider]

60. The volatiles driven off during pyrolysis can be turned into fuel or fertilizer

Replying to kristopher's post #59:

Pyrolysis drives off hydrogen and light hydrocarbons from the wood, leaving behind the majority of the wood's carbon as charcoal. Some of the volatiles (that are quite high in hydrogen and low in carbon) are used to provide process heat for the pyrolysis. Using the Fischer-Tropsch process the unused portion of the volatiles can be turned into synthetic diesel fuel, or by using steam reforming can be cracked to hydrogen. The hydrogen can then either be sold as-is, or turned into ammonia for fertilizer using the Haber-Bosch process. Here's a page on a company that's trying it out: http://www.eprida.com/hydro/

That's how it helps.

[OKIsItJustMe]

61. See Also

http://en.wikipedia.org/wiki/Biochar#Production_of_biochar

The yield of products from pyrolysis varies heavily with temperature. The lower the temperature, the more char is created per unit biomass. High temperature pyrolysis is also known as gasification, and produces primarily syngas from the biomass. The two main methods of pyrolysis are “fast” pyrolysis and “slow” pyrolysis. Fast pyrolysis yields 60% bio-oil, 20% biochar, and 20% syngas, and can be done in seconds, whereas slow pyrolysis can be optimized to produce substantially more char (~50%), but takes on the order of hours to complete. For typical inputs, the energy required to run a “fast” pyrolyzer is approximately 15% of the energy that it outputs. Modern pyrolysis plants can be run entirely off of the syngas created by the pyrolysis process and thus output 3-9 times the amount of energy required to run. Alternatively, microwave technology has recently been used to efficiently convert organic matter to biochar on an industrial scale, producing ~50% char.

…

[GliderGuider]

37. So we take organic matter out of agricultural soil and dump it in the ocean?

While we're talking tradeoffs, that one needs to be given the gimlet eye.

[GliderGuider]

52. If too much human activity is the problem, then charcoal may indeed not be the answer

From an abstract perspective, charcoal making increases both the activity level and the technology level of human activity, relative to dealing with raw biomass. What we're talking about here is really just another technique for geo-engineering. Given the amount of skepticism we apply to other forms of planetary modification, it's a good idea to be skeptical about this one as well. Unintended consequences lurk everywhere, especially when we try to scale up local processes to planetary dimensions.

So if we discount charcoal as a realistic approach for pulling huge amounts of carbon out of the air, what are we left with? As far as I can tell, we have reforestation and pumping liquid CO2 into empty natural gas fields...

If Lovelock is right about it being too late for emission controls to do any good (and I agree with him on that point), then as far as I can tell we are now well and truly screwed -- so long as the objective is to preserve human activity, affluence and numbers. Of course, if you were to take take any of those three out of the equation, the picture changes.

The sure bet for returning the planet to some sort of balance is to let nature take its course and trim our numbers.

[phantom power]

51. Fooooooood fiiiiiiiiiiiight!

[GliderGuider]

53. And here I thought

that it would be Lovelock's projection of only a billion people remaining by 2100 that would be controversial. But I guess compared to smoke and soot, gigadeaths are no big deal. :evilgrin:

[phantom power]

55. Well, we've had that food fight before, too.

Eugenecist pig!
Cornucopian Pollyanna!

[IrateCitizen]

62. Mother Earth News has an article on charcoal fertilizing in its current issue

Regardless of the debates about the merits of agricultural charcoal as a method of carbon sequestration, the fact remains that it is an effective means of organic fertilizer that has been utilized for millennia.

Sorry for the lack of a link, I received the issue this week but they haven't updated it yet on their website.