Drifter (floating device)

From Wikipedia, the free encyclopedia
Jump to: navigation, search
A drifter nicknamed holey sock. Typical sensors acquire air pressure, sea surface temperature, irradiance and CTD.

A drifter (also float) is an oceanographic device floating on the surface or at a given water depth to investigate ocean currents and other parameters like temperature or salinity. They are also called Lagrangian drifters since they follow the flow in a Lagrangian manner. The depth of drifter is defined by its neutral buoyancy. The device stops sinking when its buoyancy force is in equilibrium with its gravitational force.[1]

Construction principle[edit]

The major component of a drifter are hollow bodies that ensure flotation, underwater-sails to catch water currents, instruments (e.g., data collecting instruments, transmitters to transmit the collected data, and GPS devices), and waterproof containers for instruments.[2][3] Drifters are a hi-tech evolution of the ocean current analysis by means of drift bottles, which in their turn evolved from simple collection of data about messages in a bottle.


Drifters provide real-time information about ocean circulation. The data is a valuable input for weather forecasts as meteorological satellites can at maximum measure the sea surface temperature or the surface roughness of the world oceans, but it is not possible to look into the water column. Data from inside the ocean is helpful for hurricane prediction as well.

Drifters may also collect information about marine life, such as distribution of plankton.[2]

Different types[edit]

An Argo float
  • ALACE (Autonomous Lagrange Circulation Explorer)[4]
  • Argo float[5]
  • PALACE (Profiling Autonomous Lagrange Circulation Explorer)
  • Davis drifter[6]
  • Polar Profiling Float
  • SOFAR float[7]
  • SOLO
  • Swallow float

See also[edit]


  1. ^ Budeus, Gereon. "Floats – free drifting underwater buoys". Alfred-Wegener-Institute for Polar- and Marine Research. Retrieved 2012-09-13. 
  2. ^ a b "Drifters"
  3. ^ "Dissect a Drifter"
  4. ^ [1]
  5. ^ "Argo-float design". Retrieved 2012-09-17. 
  6. ^ [2]
  7. ^ [3]

External links[edit]