Antarctic Iceberg Drift Speeds: Inches to Miles Per Year

Highly Variable

Iceberg velocity depends on size, draft, currents, wind, sea ice, and grounding.

Typical Ranges

• Small/medium bergs: 0.1–1 km/yr (300–3,000 ft/yr) — driven by coastal currents.
• Large tabular bergs (>10 km): 1–10+ km/yr — follow deeper currents (e.g., Antarctic Coastal Current, Weddell Gyre).
• Extreme: B-15 (2000, 11,000 km²) — up to 3–5 km/yr (2–3 mi/yr) initially.

Key Drivers

• Ocean currents (primary) — surface vs. deep keel.
• Wind (secondary) — affects smaller bergs more.
• Sea ice — can trap or push.
• Grounding — halts movement until melt/freed.
• Coriolis — deflects left (Southern Hemisphere).

Tracking

Satellite (ESA Sentinel, NASA MODIS, ASCAT) + buoys monitor major bergs for navigation safety and science.

Feet Per Year?

Most bergs: hundreds to thousands of feet per year. Only giants in fast currents reach miles/year.