Technology: Seagoing Ice Plow

To clear a path for commercial ship ping in the Arctic, conventional ice breakers ride up on the ice and break it downward. The technique has limitations. Forcing the ice down against water resistance reduces the efficiency of even the world's most powerful ice breakers. And broken chunks bob up astern, where they may damage cargo vessels that follow. Often the icebreakers are halted when pressure and friction from trapped floating chunks form a vise along their sides. Now a Canadian inventor, Scott Alexander, 55, has developed a new device that breaks ice upward. The new present seagoing ice...