The snowy owls’ breeding grounds are far, far north in the Arctic. Some years, they fly thousands of miles to the south, which ornithologists call irruptions. A year ago, a massive migration wreaked havoc at New York airports — a landscape that mimics the tundra.  The New York Times quoted Chris Wood, a researcher at the Cornell Lab of Ornithology who leads a project tracking sightings, saying the 2013 migration was “unlike anything most of us have seen in our lifetime in the eastern United States.... These snowy owls may well be sharing a message for us about conditions in the Arctic.”