> but I can see why someone from a place like the American Midwest might think this is true.

Ironic since I don't live in the midwest. I've visited there during summer once. :)

> The difference between -1C and 1C is something you can literally see around you. The difference between -1F and 1F is not. Anything “below zero” is literally frozen and completely inhospitable to normal human life!

I dunno, down to 20°F/-7°C, it's pretty easy to have liquid water still when hit by direct sunlight. It's also not really that extremely cold (I'm still fine with short sleeve shirts in the 20s F). 0°F/-17°C is where I'd say things get extremely cold and even direct sunlight ceases to melt water.