Ice Drift Vector

Free-drifting ice moves ~2 % of wind speed at ~30° to the right of wind (Nansen rule) in northern hemisphere, plus any surface-current contribution.

PolarIce

Surface wind speedknWind direction (from)°TSurface currentknCurrent direction (towards)°T

Ice drift speed: 0.87kn

Ice drift direction (towards): 103.3°T

Changing the inputs requires JavaScript. The calculator above shows its default inputs and result. The formula, symbols, and regulatory sources are shown in the Formula section below.

Formula, assumptions, and limits

V_\text{ice} = 0.02 V_\text{wind} \oplus V_\text{current}, \quad \theta_\text{ice} = \theta_\text{wind towards} + 30^\circ

Symbol	Meaning	Unit
$V_\text{wind}$	Surface wind speed	kn
$V_\text{current}$	Surface current	kn

Source: Nansen (1902) - Oceanography of North Polar Basin; IMO Polar Code

In short

Free-drifting ice moves ~2 % of wind speed at ~30\u00b0 to the right of wind (Nansen rule) in northern hemisphere, plus any surface-current contribution.

Learn the theory Antarctic Special Area and Polar Code: integrated MARPOL plus SOLAS regime