Ocean Circulation and Climate Dynamics

Ship based observations

Rare encounter: Research vessels Meteor and Polarstern meet near the equator at 23°W.

The observing physical oceanography group is mainly working on data measured directly in the ocean, so-called in-situ data. This means that open ocean cruises onboard the big research vessels still remain the highlights in the professional life of Physical Oceanographers. All publications and all results are somehow based on data gathered during these cruises.  


Different instruments and measurement techniques are utilised onboard the research vessels. Most important are:

CTD Probe

Even during the early cruises of the first “Meteor” in the South Atlantic during the 1920s, profiles of temperature and salinity were taken from the surface all the way down to the ocean floor, several thousand meters deep. Those measurements, tedious and time-consuming using buckets and reversing thermometers, more


ADCP Current Meter

Nowadays, most current measurements are taken acoustically, i.e. by using the so-called Doppler effect: The frequency of a reflected acoustic signal changes as the target (or reflector) moves relative to the sound source (transponder). This phenomenon is well known as the sound of a passing car  more


Microstructure probe


Tracer Release

 The open ocean tracer release experiment is an accurate method to investigate the turbulent vertical mixing and horizontal dispersion in the ocean. The experiment starts with the release of a chemical compound, concentrations of which are detectable even when strongly diluted. With time, the tracer patch spreads horizontally and vertically, its spread monitored by several cruise campaigns.   more