Fig. 1. Schematic representation of a drift dive, showing the original sampling points, the inflection points stored and transmitted by the Satellite Relay Data Logger (SRDL) and the reconstructed time-depth profile. The drift rate is calculated as the slope coefficient (d/t) of the best-fitting regression line. Here, only the regression line for the entire segment between d₁ and d₄ is shown, but in the actual selection process three different regression lines were evaluated (see text for further details).