Please simplify. How much carbon on how much land?

[Pangolin]

I'm trying to get a grasp on the problem and some very basic facts are not easy to get in a format that is understandable to the layman. Here are my questions.

 

How much excess carbon (not carbon dioxide) is in the atmosphere?

 

What is the net annual increase in that carbon?

 

At the density of lump charcoal how much volume is that total? Per capita? Expressed as per capita national emissions?

 

As a US citzen how much charcoal do I have to dig in to offset my yearly emissions? Can we express that in cubic yards?(like sand)

 

What is the maximum reasonable charcoal input on a given acre of land?

 

How much agricultural land in the world do we have that we could reasonably use for Terra Preta sequestration?

 

The paragraph(s) I'm trying to construct is this: As a citizen of "X" country we would have to bury "Y" tons of char on "Z" acres/hectares of land to offset your yearly emissions. That charcoal would fit into a "umpty" yard dumpster.

 

Because you are "N" years old there are also "Q" tons of carbon in the atmosphere that represent "Y" tons of charcoal that need to by buried on "V"acres of land.

 

Could we please either find a calculator that has these answers or construct one ourselves?

 

The reason that I want the CO2 figures expressed in cubic yards of charcoal/acre is that people can vsualize what this means. When the BBC talks about "tons of CO2" they might as well be talking about tons of helium for all this reallly means to me. What I want to express to people is that thier current emissions represents so many truckloads on charcoal that we could dump on their driveway and demand they bury.

 

:(

[jackson33]

i can only answer with my limited knowledge or understanding, but maybe it will get the conversation going;

 

carbon is classified as a trace amount of the planets material, however is stored primarily in plant life, the ocean and makes up a great deal of whats in fuels. its the easy burning which requires oxygen, that makes it efficient. the last suggested guess for an amount was 60 trillion tons in plantlife and dwarfed by whats stored in the oceans. this is not CO2...

 

earths crust and matter make up; Oxygen 46.6%, Silicon 27.8%, Aluminum 8.1%. Iron 3.6%, Sodium-Magnesium and Potassium 2 to 3 % each. others 1.6%...

 

now if you asking how much CO2 in is the atmosphere, according to Enc.Wik; the amount is about .046% of the total. Nitrogen is 77.0% and Oxygen is 22.0% with trace amount of other. parts per million or of CO2 are 3 to 350 generally in the lower atmosphere. (remember thats per million)

 

tons of CO2 are the weights of carbon and oxygen, combined after produced by some action. you breath out, a combination, which CO2 is a small part.

as to off setting, if you think its required, planting of trees, shrubs or even a garden use and store carbon, additionally giving off oxygen. parts per million, would be the best way to address what causes are, however would not make the point many try to make an issue.

[Pangolin]

I have run across several posts in blogspace that combine to form a very frightening picture.

 

The first here on bioenergy has a table that would indicate that as an average US citizen emitting 20 tons CO2 per year I would need to find 1 1/2 acres of farmland that is willing to bury the 30 yard dumpster's worth of carbon my emissions add up to.

 

Now I'm 42 so I can presume that CO2 emissions are calculated on a per-capita basis so I need space for my other 41 years worth of emissions. Lets call that another 60 acres and another 40 dumpsters of charcoal. That just gets me to break even.

 

Now here's the real stinker. My 1/6 billionth share of the worlds arable land is about an acre according to this story on Gristmill. That means that I have to find 60 people in the third world who will cut, burn, and bury six tons of carbon for me; each.

 

I'm really hoping I've got the math wrong here.

 

My ultimate goal is to set up a demo that allows people to calculate their CO2 output and give them a truckload measure of their carbon debt and useage. The ultimate image would be a new SUV with a bow around it towing it's carbon behind it as carbon. Likewise the person getting off the plane in Hawaii being given a lei and being led to the dump truck carrying the carbon from their flight.

 

But we have to have accurate measures of volume.

 

Comments? :shrug:

[Zythryn]

It may be simplest simply to figure out the volume of one ton of carbon. There are a number of sources for how many tons of carbon are added to the atmosphere by different activities. Your 20 ton per year per individual sounds about right.

[Turtle]

It may be simplest simply to figure out the volume of one ton of carbon.

 

Then again, maybe not. The weight/unit-volume ratio is dependant on the particle size of the carbon (charcoal), as well as what type of material is carbonized and the degree of carbonization. The finer the particle for a given 'batch', the greater the weight per unit volume. :hihi:

:shrug:

[jackson33]

Pangolin; in your frustrations, remember the tons of all CO2 by all sources, primarily in nature and then by man (95% vs. 5%) is very little of the total tons of atmosphere. remember parts per million. just as oxygen is our method to clean the body system producing many chemicals, the entire plant life system requires that CO2, to live and coincidentally produce much of the air we breath and the food we eat.

 

getting directly to the perceived hysteria or that man is creating some kind of problem for nature or the weather patterns, the ideas leave out normal cycles of change. these changes have occurred and will again. the past 800k years or since the planets first really complex ice age the atmosphere as remained fairly constant, at least the lower troposphere. man could have existed at anytime since then and indeed much of life has its origins in this period. the maturity of what is now formed about 55 million years ago, leading to mammals, grass, primates, sea life of today and in the past 3 million years or so mans ancestors. but during this same period the planet has cooled and heated many times and to degrees much greater than the suggested current change. our industrialized society of today, is a new feature and there is no indication, we have changed anything with in these natural cycles.

 

you mentioned your little space on the planet. to me this is another misnomer

addressed by environmentalist. if all the people on earth moved to Texas, the population density of Texas would be about 36 people per acre. this is far less than the density of many cities today in the world. if you want the figures Texas has about 262,000 square miles, there are 640 acres per sq. mile and i used 6 billion people. by the way that would leave over 198 million square miles with nobody on it, noteing no one is on over 1/3rd now...

[Zythryn]

Jackson, you are doing your best to hijack this thread aren't you;)

To the original post, and Turtle's response.

Very good point Turtle. However, in looking for the volume of carbon burned I THINK the original poster is looking for the volume of carbon added to the atmosphere. So this volume would be that of JUST the carbon, not the impurities. Or, possible just the mass of CO2 added to the atmosphere as I think that will be more commonly found.

[jackson33]

Jackson, you are doing your best to hijack this thread aren't you;)

To the original post, and Turtle's response.

Very good point Turtle. However, in looking for the volume of carbon burned I THINK the original poster is looking for the volume of carbon added to the atmosphere. So this volume would be that of JUST the carbon, not the impurities. Or, possible just the mass of CO2 added to the atmosphere as I think that will be more commonly found.

 

i read the thread as an attempt to make sense of the declared out puts of human CO2 contributions and the carbon offset principle. while i have added, some other items to clarify what explanations i have made. this was quite evident in the authors second post. in logic, the idea a 1 or 2 hundred pound person can produce 20 tons of something each year and responsible for additional amounts in tons per, is at best mis-leading. taking it to practical terms, units per, make much more sense, placing the acts of existence minimal to the over all picture...

[Pangolin]

One of the biggest problems when understanding the climate change problem is that most people really don't understand the problem. The science of anthropogenic global warming is well established and reliable enough that we can regard it as a fact. (note: flat earthers please crawl back into your Exxon funded holes at this point). The problem now is 1)How do we quit adding GHG's to the atmosphere and 2)How do we scrub out the excess that's there. Terra Preta deals with #2.

 

The Peak Oil discussion has a very effective visual aid; current yearly oil consumption amounts to about a cubic mile of oil yearly.

 

What we don't have as a means of understanding the CO2 problem is a visual image of excess carbon in the atmosphere. The common phrasing "x tons of CO2" means absolutley nothing to people. (which might be why the media prefers it) People need a visual image. Therefore....

 

At the average density of hardwood charcoal what volume of excess carbon exists in the atmosphere?

 

What volume of said carbon represents the average yearly addition of a US citizen? Of a EU citizen?

 

At the highest reccomended application of agrichar for Terra Preta soils how many acres are needed worldwide to offset one years emissions? How many acres per US citizen? Per EU citizen?

 

How many acres of agricultural land are available?

[Pangolin]

i read the thread as an attempt to make sense of the declared out puts of human CO2 contributions and the carbon offset principle. while i have added, some other items to clarify what explanations i have made. this was quite evident in the authors second post. in logic, the idea a 1 or 2 hundred pound person can produce 20 tons of something each year and responsible for additional amounts in tons per, is at best mis-leading. taking it to practical terms, units per, make much more sense, placing the acts of existence minimal to the over all picture...

 

I see no attempt to clarify but rather one to mislead. :hihi:

 

Anthropogenic Global Warming caused by an excess of CO2 emissions is not up for discussion in this thread. For purposes of discussion in science forums it can be regarded as fact. There are discussion groups for doubters here. This is the Terra Preta discussion group.

 

As a means of understanding the uses of Terra Preta it would be usefull to know how much we need for the job[/a] i.e. reducing atmospheric CO2 and/or improving farmland. It would be helpful to know this in units that are in use by the layman i.e. cubic yards of charcoal. It would also be usefull to know minimum and maximum usefull application spread rates in acres and or/sq ft. Just like any other soil amendment.

[Turtle]

...

As a means of understanding the uses of Terra Preta it would be usefull to know how much we need for the job[/a] i.e. reducing atmospheric CO2 and/or improving farmland. It would be helpful to know this in units that are in use by the layman i.e. cubic yards of charcoal. It would also be usefull to know minimum and maximum usefull application spread rates in acres and or/sq ft. Just like any other soil amendment.

 

The current situation is that we have no definitive answers to these questions. It is experiments and reporting on those experiments by interested folks like you that may change that.

 

For the agricultural side, get some charcoal, measure its volume after crushing it into variable sizes from powdery to around 3mm, and then weigh it. I would suggest mixing it at a rate of 20% by volume of your existing soil. Then grow as usual and note any differences.

 

I haven't run across the actual carbon content of charcoal(s)*, but finding that, then you can calculate how much carbon you have sequestered. In one of the threads here on terra preta - or a link in one :hihi: :hihi: - it was suggested we would have to bury the charcoal to a 3 foot depth on current agricultural land. :hihi: For simple sequestering purpose, we needn't use only agricultural lands I think. :hihi: :hihi:

 

*Post Script: It's not as simple as it may seem. Bold emphasis mine. >>

Abstract Diffuse reflectance Fourier transform infra-red spectroscopy (DRIFT) has been used to characterise the chemical nature of a range of charcoals produced from different woods and with differing carbon contents. The technique is simple to perform and high quality spectra are reported for total carbon contents of up to 92.5%. The work shows that carbonisation of wood results in a graded change in chemical nature from a material rich in aliphatic structures to one dominated by aromatic domains as carbon content increases.

SpringerLink - Journal Article

[Philip Small]

At the average density of hardwood charcoal what volume of ...

 

I read through the thread a little quickly, so apologies if bits of this this has already been covered.

 

Charcoal is carbon with minor impurities so it is reasonable to assume for our purposes that a ton or yard of charcoal is a ton or yard of carbon.

 

Carbon dioxide units at full molecular weight can be converted into equivalent carbon units by dividing by 44/12 (see endnotes here).

 

A metric ton of charcoal is equivalent to 3.67 metric tons of carbon dioxide.

 

A cubic yard of hardwood charcoal weighs about 475 lbs. (based on one (1) 8.8 lb, 0.5 cu ft, bag Cowboy brand hardwood charcoal) >> Revised per new information and correct calculations: A cubic yard of charcoal, at 250 kg/m3 weighs 148.6 lbs.

 

A ton of charcoal is about 13.5 yards.

 

A metric ton of charcoal is about 14.8 yards.

 

A metric tonne of carbon dioxide contains about the same amount of carbon as 4.04 yards of (pure carbon) charcoal.

 

Corrected lb/ft3 per formula kg/m3*2.2 lbs/kg*(((0.3048 m/ft)*3ft/yd)^3)m3/ft3=lbs/ft3. lbs/ft3 * 27 = lbs/yd

[Turtle]

I have some 'horticultural charcoal' still left, so I weighed it.[bag says Product of USA, Red McLellan Co, Whitney Farms, PO Box 70, Independence, OR 97351, Whitney Farms Organic Garden Products Mind you, particle size IS extremely important to weight per unit volume, and I will have those experiment results presently.

 

Since my source shows the highest carbon content charcoal is only 92.5% carbon, I think Phillip's estimates are too large.

 

So, 1 cup of 'horticultural charcoal' pieces in the 1cm to 2cm size range weighs 93.272gms.

 

1 cup of my native soil weighs 242.354gms

 

I have 1/2 cup of the charcoal bits in my mortor, and I will measure the volume after crushing them to fine particles. Regardless of what the other fellas tell you, size matters.

[Philip Small]

A metric tonne of carbon dioxide contains about the same amount of carbon as 4.04 yards of charcoal.

 

Revised to 4.25 yards of charcoal needed to offset a metric tonne of carbon doxide.

 

Carbon content of charcoal appears to be between 95 and 99 percent (see here). The 1-5% is ash and non-C components of volatile/aromatic constituents. At 95% C, it takes 4.25 yards of charcoal. (see additional revision in later post)

 

The density of charcoal used in the previous post (17.6 lbs/ft³) does not seem to bear out in other references:

Density of charcoal is expected to be between 250 kg/m³ (5.5 lb/ft³) and 300 kg/m³ (6.6 lb/ft³). Rail freight for charcoal is calculated on the basis of 300 kg/m³ of charcoal.

 

Corrected lb/ft3 per formula kg/m3*2.2 lbs/kg*(((0.3048 m/ft)*3ft/yd)^3)m3/ft3=lbs/ft3.

[Philip Small]

Revised to 4.25 yards of charcoal needed to offset a metric tonne of carbon doxide.

 

Revised (yet again) to 4.64 yards of charcoal needed to offset a metric tonne of carbon dioxide, per carbon content of charcoal at 87 percent. (pdf source)

 

Note: corrected per conversion error

[Turtle]

Carbon content of charcoal appears to be between 95 and 99 percent (see here).

I see only the 92% figure at your link; in the table and associated with 700degC process.

 

The density of charcoal used in the previous post (17.6 lbs/ft³) seems to bear out in other references:

Density of charcoal is expected to be between 250 kg/m³ (15.6 lb/ft³) and 300 kg/m³ (18.7 lb/ft³). Rail freight for charcoal is calculated on the basis of 300 kg/m³ of charcoal.

 

Accessing... I'll scale up my measure to compare with your accredited figures.

 

So again, the particle size matters! A lot! The 'standard' ratings of so many tons per this or that conveyance are of little worth if the particle size is not noted. My 1/2 cup of 2 to 3cm pieces ground down to 1/3 cup of sub-milimeter chunks and powder. A reduction of 1/3 in volume with no change in weight.

 

Also, the % of carbon is highly variable depending on the specific wood used and the temperature used to cook it. If we want a real idea of the answer we need the variability of each factor plotted as a graph and then all against each other ala linear programming.

[Turtle]

...Density of charcoal is expected to be between 250 kg/m³ (15.6 lb/ft³) and 300 kg/m³ (18.7 lb/ft³). ...

Accessing... I'll scale up my measure to compare with your accredited figures.

 

 

Scaling my actual measure for charcoal of 93.27 gms/cup to kg/m³ gives a figure of 230 kg/m³ (5.07 lbs/foot³; 137 lbs/yard³) for density of horticultural charcoal chunks in the 2cm to 3cm range.

 

 

Work >> 1 cup charcoal weighs 93.272 gms * 16 cups/gallon = 1,492.35gm/gallon * 7.48 gallons/foot³ = 11,162.79 gm/foot³ / 1,000gm/kgm = 11.16279 kgm/foot³ / 2.2 lbs/kgm = 5.07 lbs/foot³ * 27 foot³/yard³ = 136.99 lbs/yard³ * .765 = 104.79 lbs/m³ * 2.2 kgm/lb = 230.5 kgm/m³