If the Gulf Stream changes, that could be really bad. You know how the British Isles don't have severely cold winters even though the entire region is north of the 49th Parallel? The Gulf Stream is one of the big causes of that. If the Gulf Stream changed, we wouldn't have a "Day After Tomorrow" style apocalypse, but the UK and Ireland would get some very
cold winters they aren't prepared for. It would probably effect Scandinavia as well, along with wherever the Gulf Stream redirects to.
The jet stream that holds back most of the arctic air's gotten messed up (that's part of why the Polar Vortex moved in), and that's a lot more minor than what could happen in the future. Toronto's supply of migratory birds is way down this year, because it snowed heavily after
they arrived. Of course, the prediction for the summer is that it will be blisteringly hot. Like it has been the past few years.
edited 6th May '14 7:55:06 PM by Zendervai