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13

Summary Most of the remaining stocks of hydrocarbons (coal, natural gas, oil) will have to remain unburnt. In almost all cases, that will mean leaving them in the ground. We already have proven technology to prevent new emissions of anthropogenic greenhouse gas emissions, and in most cases, the technical and economic barriers are solved: the remaining ...


13

To answer your question to the point: we don't know at all. For most of living organisms, the fossil record is either inexistent or very fragmentary. Even estimating the number of species (which is somewhat less difficult since you need only one specimen of each species to have access to that information) is very difficult and affected by many, many ...


10

1.How much carbon is there on Earth? Taken as whole, the Earth is estimated to be 730 parts per million carbon by mass. So $4.4 \times 10^{21} kg$ http://quake.mit.edu/hilstgroup/CoreMantle/EarthCompo.pdf How much carbon is there in the atmosphere (in the form of CO2 and CO)? $3.1 \times 10^{15} kg$ CO2 and insignificant CO, so $8 \times 10^{...


10

No, we do not need to stop extracting petroleum, we need to stop burning petroleum, as well as other fossil fuels, because combustion converts solid C to gaseous C, and hence goes up to the atmosphere, increasing the amount of greenhouse gases that warm the planet. No, we do not need to convert existing CO2 into diamonds. Plants are pretty good taking up ...


8

As you say, the existence of organism that live out of chemical compounds expelled by hydrothermal vents (Chemoautotrophs), immediately render the sentence "All life on earth gets its energy from the sun" as an approximation. However, some approximations are pretty good for all practical purposes. Nevertheless, this approximation (even if right), have some ...


8

The oxygen in the atmosphere was produced by cyanobacteria during the Great Oyxgenation Event, around 2.3 billion years ago. Cyanobacteria produced & still, produces, to a lesser extent, oxygen by photosynthesis. Plants did not exist during the Great Oxygenation Event, but these day plants replenish atmospheric oxygen by removing carbon dioxide by ...


3

There are various charts but not exactly what you want. This one combines burning, industry and cement but shows land sources and sinks separately: CarbonBrief, Le Quéré, C. et al. (2016)


3

David LeBauer is correct in saying that there are 'allometric equations' to estimate the leaf biomass, but they only refer to small experimental plots in such places as Hawaii, Japan, Singapore and Malaysia. The number of species involved is a few dozen at most. As 'N9ZN' points out, trying to develop generalizations would be a titanic task, and essentially ...


2

Estimates of earth's total biomass vary widely, from 0.5 to 4 trillion tons C, so instead of citing a source, I'll just go with an assumption of $1\times10^{15} \text{kg C}$. Measuring biomass in carbon is a convenient segue to the next assumption: assume that all biomass burns only in $\text{CX + O}_2\,\rightarrow\,\text{CO}_2 + \text{X}$. Given these ...


1

Wow, I just finished watching this it seems we know, or can guess, quite a bit about the level of Carbon, particularly Methane that were released at the end of the Permian and what they did to the climate. What seems to be missing is any consensus about why the Permian extinction stopped just that once things settled down climate and atmosphere swung back to ...


1

Yes today’s photosynthesis is occurring but so is the oxidation of the carbon based plant material when they decay and consumed. In order to have a surplus molecular Oxygen quantity the products of photosynthesis cannot undergo oxidation. Our biggest threat is the diminishing of molecular Oxygen because that is what absorbs UV energy and releases it as ...


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