[londons_explore]

When that happens, people will set fire to a coal seam or open a gas well because it's a cheap and easy way to maintain the climate at 'current' levels.

When people grew up in a 4C warmed world, that is the way they'll want to keep it.

[polotics]

Nope! A 4 degrees average rise means massive chaos of climate ups and downs, no one is going to be happy with that. Also note that extreme North/South location do not get good sunshine for plant growth, it's too low on the horizon, even if the temperatures are balmy...