PMEL Earth-Ocean Interactions Program logo National Oceanic and Atmospheric Administration Pacific Marine Environmental Laboratory Earth-Ocean Interactions Program
. CTD Vertical Cast
 
  illustration of vertical cast, click for animation
Click for vertical cast animation.		  

The ship arrives at the designated location and holds position as well as possible (depending on weather conditions and the ship's basic capabilities) while the CTD is lowered then raised again through the water directly beneath the ship.