🧊 Nobody steers these

Every dot is a tabular iceberg, a slab of ice broken off an Antarctic ice shelf and tracked from space. The wake behind it is where it has been over the past two years. This is 1999 to 2026, around forty to sixty of them under watch on any given day.

🛰 How you track a block of ice in the dark. These are followed by scatterometers, radar instruments built to measure wind over the ocean. Ice reflects the radar far more strongly than seawater, so an iceberg shows up as a bright spot that can be followed through polar night and through cloud, when no camera could see anything at all.

🌀 Watch where they go. They don’t scatter at random. Most of them hug the continent, carried westward by the coastal current, until they reach the Antarctic Peninsula and get flung north into the Atlantic. That corridor towards South Georgia is travelled so consistently it has a name: iceberg alley. Once a berg enters it, warmer water starts eating it from below and it usually has a year or two left.

📏 Size matters here. The marker carries the real length of each berg, exaggerated so the difference is visible. The median one is about 30 km long. The largest in this record is nearly 180 km, longer than the island of Gran Canaria is wide, and those giants can survive for decades: one track in this database runs for 34 years.

⚠️ Calving is not melting. Ice shelves shed icebergs as a normal part of their life cycle, and a spectacular calving event is not by itself evidence of anything. What matters is whether a shelf regrows what it loses. That’s a different question, and this animation doesn’t answer it.

⬇️ One honest gap: around late 2009 the bergs almost vanish from the map. That is not the ocean, it is the loss of the QuikSCAT scatterometer before another instrument took over routine tracking.

📊 Data: BYU MERS Consolidated Antarctic Iceberg Database