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How coal was formed Regarding coal, from trees, it's not simply a question of the area whether it was a continent-size landmass, but more of the temporal side of things -- how long a time period the land was covered. Coal was laid down from plant matter during the Carboniferous period, which lasted 60 million (60,000,000) years. For most of that time the ...


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This Zero Carbon Britain report gives a detailed answer to your question. Their plan sees emissions being reduced to 8% of the current levels, and the rest being balanced by carbon capture. This requires, they suggest, setting aside around one third of Britain's land area for carbon capture and one sixth for fuel (bio-fuels ... land area for solar isn't in ...


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tldr: yes, with sufficient political will, an incremental approach is sufficient - we could decarbonise our energy consumption in 20 years. There are still a lot of unknowns (like just what we do about long-haul aviation, intercontinental shipping, cement production). However, some things we can be sure about, and one of them is that there's way more than ...


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Burning grass is effectively carbon-neutral: the carbon dioxide released will get pulled right back out of the air next year as the grass re-grows. Cutting it and letting it decompose would also be carbon-neutral, just taking longer for the carbon dioxide to be released. If you want to stop the grass from being burned, you'll need another argument. I ...


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Where I live, forests reach a density of 100-200 cubic meters of growing stock per hectare. One cubic meter equals one tonne of carbon dioxide. From 1870 to 2014, cumulative carbon emissions totaled about 545 GtC. This is about 2000 GtCO2. So, you need 10-20 gigahectares of land. It is 100-200 million square kilometers. Unfortunately, world forest area is ...


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As a guide, mature sitka spruce forest in the UK has 500m3 of wood per hectare report; This wood has a density of 450 kg/m3 density tables, to that makes 225 tonnes of wood per hectare. The wood is about 50% carbon, so that would convert to 110 tonnes of coal per hectare (the carbon content for wood is discussed by Lamlon in Biomass and Energy). This ...


1

I don't think this question can have a very definite answer because of the enormous time involved. It takes time for mountains to break up into chemical rich dust, and it is really only on land that has risen out of the sea that things could start to grow at first. There may have been enormous tracts of desert for many eons, with plants gradually spreading ...


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