Waitbutwhy put it well: “ 18,000 years ago, global temperatures were about 5ºC lower than the 20th century average. That was enough to put Canada, Scandinavia, and half of England and the US under a half a mile of ice”
That's not really helpful, when you think about it: Are the effects linear? How much ice would the US be under for temperatures of 1°C below 20th century average? A fifth of half a mile? No ice at all? And what does that imply for 2°C above? 0.2 miles of ice below the surface?
I prefer actual predictions of the effects, not bad analogies or useless data points.
Sure, it's unhelpful if you're trying to build a model or understand the science, but 90% of people aren't; and it's accurate –if unhelpful– analogies like this that get those people onboard.
