I ask this question because in my fictional world, I want to create extremely cold, populated areas, especially in Northernmost areas, but I noticed that in our real world, regions with less than -30°C average temperature by year are usually uninhabited. But in my fictional world, I would want to make sure that some people could survive in areas with extremely cold weather.
Do you know how people could do this?
Thanks you for your answers, and have a good day!
Edit 1 : I also recently learned that a landlocked region in far North/far South was usually significantly colder than a region in far North/far South bordered with oceans and seas.
Edit 2 : I want technological solutions, not biological changes, because my fictional world is a remix of our real world.