Draft Change with Water Density
How much the draft changes when a ship moves between water densities - sea to fresh, fresh to brackish, arctic to tropic.
Inputs
Change of draft
0.187m
Ship sinks
New draft
7.687m
Formula, assumptions, and limits
Derivation: displacement Δ = ρ·V = constant, so T₂/T₁ = ρ₁/ρ₂ for a wall-sided ship at the water line. Ship sinks when ρ drops (FW less dense than SW).