It might be a problem, but I don’t think it’s the cause of extreme weather and climate change (or scarcity, poverty, hunger etc.). The dominant economic and political system is.

Also I believe it will be eventually possible to either build comfortable cities in deserts and permafrost tundra (or even on the sea floor) or transform those to less hostile biomes (although there are ethical and aesthetical considerations) provided we don’t go extinct due to climate change before we have a chance to address overpopulation concerns.