The Gulf Stream, which currently keeps Europe warmer than it should be, could be disrupted by sudden dumping of cold fresh water from Greenland. As I understand it, the fresh water is lighter than salt water and will essentially disrupt the Gulf Stream. Previously, It was believed that if the Gulf Stream were disrupted, Europe would plunge back into the temperatures that you see at the same latitudes in North America. The equivalent latitude for Belgium would be Winnipeg, which has exceptionally cold winters.
Now, you would think perhaps this would then balance out. The problem is that the Gulf Stream dissipates heat from the equator into the northern latitudes. Heat is what drives hurricanes. With nothing dissipating heat from the equator, you have an enormous, essentially battery, to power more frequent and larger hurricanes. Now before you start saying goodbye to Florida, consider that hurricanes ride along on the Gulf Stream. With it disrupted, where are those hurricanes going to go?
This is why weather modeling is so difficult. There are way too many variables to have to account for. Go ahead, try to make a prediction for more than two-three weeks.