They believe the sun rotates around the north pole, and the south pole is a huge ring around the outside. So the sun would be furthest from the north pole/south pole hence the cold.
However they're unable to explain seasons without saying that "the sun must travel in a larger circle over the southern countries during their summer"... They're also unable to explain sunrise/sunset without inventing a new way to determine an objects apparent position due to perspective (otherwise it's obvious that the sun would never set)... But then their own warped view of perspective fails when you consider that the larger/smaller circles previously mentioned would mean the sun would have to be setting/rising at different distances "due to perspective".
It's about at this point they reply with "oh well it's celestial gravity and or magnetism curving light" without providing any details what so ever of such a crazy concept, but at the end of the day they don't really care about evidence, logic, observation, or good old fashioned science, because they're much to busy for that sort of thing and it's up to us round earthers to convince them, because apparently thousands of years of evidence and observation matching conclusions isn't good enough.
Welcome to the "debate"!
