The Arctic's temperature is way above normal for the time of year. The water is much warmer after the summer ice loss and there is a flood of warm air coming up from the South.read more here
The unusually high temperatures reduce the temperature differential between the Arctic and lower latitudes and mean that the jet stream starts to slow down and meander bringing unusual weather to populated areas.
This is probably the fastest way that climate change will affect people in the heavily populated regions. Waiting for crops to fail when the temperature rises 2 C will take another thirty years and waiting for the ice to melt and raise sea levels is a slow business but this is quick. Reduce Arctic ice cover, temperature rises and straight away the jet stream moves course.
It can bring excessive rain and floods or it can bring dry weather becoming drought, but in either case it is quick, it is regional and it is very unpleasant and expensive.
These are maybe the only things that governments understand about dealing with climate change if they are able to look beyond their little bitsy power deals and are willing to deal with it at all.