Now I am not a meteorologist (so I wont bother attempting to come up with some explanation as to why) but the melting ice will cause the jet stream to move which will mean that the warm air it brings from the Gulf of Mexico will not come to the UK. Now take a look at a world map, any will do: put your finger on the UK and move it in a straight horizontal line (either left or right) and where do you end up? Canada or Russia (depending on if you went left or right). The climate in these countries is a lot colder than in the UK and if the jet stream moves then we will most probably receive cold weather like them (especially up north). This will mean that we will see a lot more snow throughout winter which will make it a no hike time for those of us who haven't been trained to cope with snowy conditions (using ice axes, crampons, checking for avalanche risks etc). You have to remember however that this will happen over a long time, not overnight. All that it will mean in hill walking terms however is we will have to cram more hikes in the spring and summer period and attend a winter skills course if we want to head to the hills in the snow. Of course the change in climate and more recently a lot more rain (whilst the jet stream is above England): the Highlands will get away with amazing mountains and amazing weather (lucky gits) will have greater implications for tourism and seasonal businesses but there is nothing we can do so we are just gonna have to deal with it.