Several years ago I went to Greenland on a travel writing assignment. Getting there was a trip in itself. First I flew from New York to Ottawa, then from Ottawa to Iqaluit, Canada on commercial airliners. In Iqaluit, I hopped an eight-seater charter jet for the journey over the Greenland Sea.   It was an exciting flight. Halfway there, at 25,000 feet or so, one of the baggage compartments popped open, releasing the Canadian pilot’s gear into the cold, cloudless skies. I couldn’t see what was happening from my side, but I heard him groan, “Oh shit!” and I thought we were...