Every Sunday for the past seven months, about 60,000 live North American lobsters packed in wet newspapers and Styrofoam coolers make the 18-hour flight to Asia in a Korean Air Lines Co. cargo plane. The 7,500-mile (12,000-kilometer) trip from Halifax, Nova Scotia, to Shanghai via South Korea has become a weekly routine this year with a surge in demand from China, where lobsters caught in North Atlantic waters are at least one-third the cost of competing supplies. As a result, exports have skyrocketed fro