The iceberg that broke off Greenland’s Petermann Glacier last week was without doubt an impressive chunk. At almost 50 square miles, the slow-moving mass of ice is one and a half times the size of Paris, 6,400 times the size of Harrods in London…and one half the size of the iceberg that broke off of the same glacier in 2011. Scientists have raised concerns that in recent years the Greenland ice shelf has been calving (the glaciologist’s term for spawning icebergs) with greater and greater frequency in recent years–a natural phenomenon that cannot be directly linked to global warming, but which nevertheless represents a worrisome trend for shipping and off-shore oil platforms in the North Atlantic’s “Iceberg Alley.”
The trouble with calving glaciers is that once an iceberg makes its way to the sea, it splits into many smaller chunks of ice, which move unpredictably and because of their smaller size become increasingly difficult to track by satellite. The playful names assigned to these smaller chunks– “bergy bits” and “growlers,” for instance–bely the seriousness of their size; a bergy bit boasts the dimensions of a grand piano, a growler those of a smallish house. And while the U.S. Coast Guard has resorted to a colorful variety of assaults designed to neutralize the iceberg threat–including dying them bright colors, shooting them with water cannons, or even dropping bombs on the hapless floes–they remain a serious threat and one that will only grow in the future. In Antarctica’s Pine Island Glacier, for instance, a 30-mile long crack has recently been observed. The iceberg that will form as a result, expected to calve later this year, will be approximately 340 square miles. This is of course a difficult figure to quickly imagine. For reference, the drifting adventurer will be the equivalent of 165,000 football fields, eight times bigger than the island of Ithaca, and five times the size of the European nation of Lichtenstein. // Patrick Barrett
