Cruising speed measurements
Image of the month - July 2007
Map of the Ovide oceanographic cruise (left). Right, velocities measured by the onboard ADCP during the Ovide 2004 cruise, and absolute geostrophic velocities from altimetry. The two measurements are very similar. Differences are mainly due to small oceanic features, which are not seen by the altimeter. (Credits Ifremer/LPO)
Cruises are among the "classics" of oceanography. However, since the first oceanographic exploration travels, things have evolved, from the instruments point of view as well as from the systematization of the measurements. Part of the oceanographic cruises, now, are repeated regularly, in order to enable along time ocean monitoring with in situ methods. Thanks to those measurements, observation of the ocean in-depth, and correlations between ocean biology, chemistry and physics at a same point are possible -- among other things.
In situ measurements are also useful to validate satellite data, like the altimetry ones, or they can be combined to and/or they can complete them to give ocean models the measurements they need to compute the best possible results.
See also:
- Data: MADT products
- Applications: Combining sensors
Websites on this subject:
- Campagnes Ovide (Ifremer)