Climate and physical features impact population distrubuation by making it hard for people to move and live there.
.. For example if you live in Antartica like no duh thats gonna affect population distrubution becasue of the climate.
.. Also if you lived ontop of the appalacian mountains.. than yea population distrubution is going to be a big issue cuz aint no body gonna move way up on top of a hill lol
