or they'll get consistently worse and you'll get really profficient at making igloos
Kind of the problem with global warming - it doesn't make everywhere hotter
(after all, it's about 2 degrees c every 20 years or so), it's main effect is to cause weather patterns to change.
At the moment the uk is heating up, but if polar melt water causes the north atlantic conveyor to shutdown (as geologic records record it does fairly regularly
(on a geologic timescale) then the uk's average temperature will drop by at least 10c - which is pretty serious.
It's only simplistic idiots that look solely at the 'warming' and think: 'why arn't I sunbathing in winter in helsinki, if stuff's warming up ?'