Boreas' Ice storm is referred to as the "Liquid Fire" in one message in God of War III, this could be a reference to Boreas the God of the North Wind having a violent temper and that it is frozen ice. Which could also mean from a part of another message "Being more powerful." giving that it has stronger effects of burning than the regular fire that the underworld or anywhere else has. In some ways ice does burn stronger than fire, because fire is less painful than Freezing in ice. Anybody who is freezing in cold will burn more, like when your hands having a stinging, similar to a burning sensation after you come inside to warm up.