Abstract: The invention relates to a method for determining a water current velocity profile in a water column by registration of a deviation between a first position and a second position of an underwater vehicle travelling in the water column. A batch of underwater vehicles is deployed from a surface vessel into the water. The vehicle(s) steers to the first position, which for the first batch is a predefined estimated position (PEP). The vehicle is by first means recording the second position, which is the actual position (AP). The difference ?P between the predefined estimated position PEP and the actual position is registered and based on the difference a deviation data set is calculated. An updated current profile or stack of horizontal water current velocities UV is determined.

Abstract: The invention relates to a method for determining a water current velocity profile in a water column by registration of a deviation between a first position and a second position of an underwater vehicle travelling in the water column. A batch of underwater vehicles is deployed from a surface vessel into the water. The vehicle(s) steers to the first position, which for the first batch is a predefined estimated position (PEP). The vehicle is by first means recording the second position, which is the actual position (AP). The difference ?P between the predefined estimated position PEP and the actual position is registered and based on the difference a deviation data set is calculated. An updated current profile or stack of horizontal water current velocities UV is determined.

Abstract: The present invention concerns an apparatus (1) for deployment and retrieval of a measurement system (8) on an ocean bottom, comprising devices for temporary storing the measurement system (8), movable control faces (7), software and devices for manoeuvring and at least one ballast tank (11A) for ballast (11B). The ballast (11B) comprises a slurry consisting of free soluble salt and a saturated solution of the salt in water, or a solid body or insoluble coarse or fine grained material.

Abstract: The present invention concerns an apparatus (1) for deployment and retrieval of a measurement system (8) on an ocean bottom, comprising devices for temporary storing the measurement system (8), movable control faces (7), software and devices for manoeuvring and at least one ballast tank (11A) for ballast (11B). The ballast (11B) comprises a slurry consisting of free soluble salt and a saturated solution of the salt in water, or a solid body or insoluble coarse or fine grained material.

Abstract: A buoy provided preferably for ascending in the water from an initial submerged position. The buoy comprises a buoyancy element positioned at an upper portion of the buoy in the ascending direction. Further the buoy comprises a storing structure for an elongated member positioned below the buoyancy element in the ascending direction, wherein one end of the elongated member is connected to the buoy and the other end of the elongated member is connected to an object submerged in the water. The buoyancy element is provided to obtain a rotation of the buoy around its central axis thereby paying out the elongated member while the buoy is ascending essentially vertically in the water.