@mercian: I agree that elevation difference (ED) isn't a great measure of flatness: it looks at the highest and lowest points and ignores the whole of the rest of the country. You could bulldoze everything but the tallest mountain and the ED wouldn't change. I did consider something like ED/area but, when you think about it, it's actually even worse and doesn't fix the problem at all. Not only does it ignore everything but the highest and lowest points but it also penalizes you for being small. ED/area says New Guinea, more than half of which is a range of massive mountains, is flatter (0.0062m/km²) than the Netherlands (0.0079m/km²).
What you'd really want to do would be to measure something like average slope of the land. But where would you find data for that? |
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