> oil and coal are far more energy dense than wood
In addition, a block of wood is a lot more dense than an acre of forest, which is a lot more dense than the difference in carbon content between an acre of forest and an acre of charred burned forest.
While reading the article, I mentally substituted "a forest the area of Africa" with "an oil tank the size of Africa and as deep as a forest is tall", which is clearly unreasonable. And they mention "4.81 tons" in passing - a ton is a lot, and surely 4.81 tons is a huge volume of gas, but how much?
We need to run the numbers. Crude petroleum has a density of about 0.8 g/cc = 0.8 ton/m^3 and a carbon composition of 85%.
4.81 tons of carbon x (1 kg crude / 0.85 kg carbon) x (1 m^3 / 0.8 ton crude)
= 7 m^3 of crude. Looking it up, a typical tractor-trailer tanker truck might carry 40 m^3 of crude...so this can be stated as mankind burning a yearly volume of one truckload of fuel for every 6 acres in Africa, which is a lot more believable.
Going back to the oil-per-acre analogy, an acre is a little more than 4000 square meters, so (assuming it's all oil - ignoring coal, natural gas, and other CO2 producers like, I don't know, human-initiated forest fires) this is a film of oil over the continent of Africa 1.7mm deep. That's a lot more believable than imagining a towering petroleum forest.
In addition, a block of wood is a lot more dense than an acre of forest, which is a lot more dense than the difference in carbon content between an acre of forest and an acre of charred burned forest.
While reading the article, I mentally substituted "a forest the area of Africa" with "an oil tank the size of Africa and as deep as a forest is tall", which is clearly unreasonable. And they mention "4.81 tons" in passing - a ton is a lot, and surely 4.81 tons is a huge volume of gas, but how much?
We need to run the numbers. Crude petroleum has a density of about 0.8 g/cc = 0.8 ton/m^3 and a carbon composition of 85%.
= 7 m^3 of crude. Looking it up, a typical tractor-trailer tanker truck might carry 40 m^3 of crude...so this can be stated as mankind burning a yearly volume of one truckload of fuel for every 6 acres in Africa, which is a lot more believable.Going back to the oil-per-acre analogy, an acre is a little more than 4000 square meters, so (assuming it's all oil - ignoring coal, natural gas, and other CO2 producers like, I don't know, human-initiated forest fires) this is a film of oil over the continent of Africa 1.7mm deep. That's a lot more believable than imagining a towering petroleum forest.