#2992: UK Coal

XKCD comic, described below.
Transcript

[The following formula is shown (with the divisors below a horizontal line in the comic, rather than inside square brackets):]

UK total coal production (1853-present, UK DESNZ) / [(coal seam density) × (UK land area)] = 25 billion tonnes / [1.3kg/L × 240,000km²] ≈ 3 inches

[Cueball is standing to the right of the formula, upon a dotted line representing the prior ground level. Two arrows indicate that the dotted line is 3 inches above the solid line that is the current ground level. One arrow goes from the end of the word inches to the dotted line the other is short and goes up from below pointing at the solid line.]

[Caption below the panel:]

The UK shut down their last coal power plant today, which means that over the course of the industrial revolution, they dug up and burned an average of 3 inches of their country.

(Sourced from explainxkcd.com)

The Watership Down rabbits removed an additional 0.1 nanometers constructing their warren, although that was mostly soil. British rabbits have historically mined very little coal; the sole rabbit-run coal plant was shut down in the 1990s.

ExplainOriginal