Does the British Isles and Norway have harsher winters because of gulf stream?

No, the Gulf Stream actually moderates the climate of the British Isles and Norway, making their winters milder than they would otherwise be. The Gulf Stream is a warm ocean current that flows from the Gulf of Mexico across the Atlantic Ocean. It brings warm water to the western coasts of Europe, which helps to keep the climate mild. Without the Gulf Stream, the British Isles and Norway would have much colder winters.