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2.3.1 Research Vessels
Description:
Research vessels are still the backbone for much of ocean research. Ships
are usually needed to deploy heavy or big instrumentation (geophysical
equipment, moorings, nets) or to collect samples for chemical and biological
analyses. These are very important applications, but the vessels are not
suited for routine, frequently repeated, operational observations – they are
very expensive and e.g. the one-time survey of the oceans with hydrographic
sections under the WOCE program took 10 years! An exception is the use of
research vessels as “ships of opportunity”, where they are used to collect
underway samples as they go to remote and ill-sampled areas for other work.
The instrumentation used then are XBTs (expendable, free-falling
temperature probes), thermosalinographs analyzing water pumped into the
ship from near the surface, and Acoustic Doppler Current Profilers (ADCP)
built into the hull of the vessels.
Application:
When using research vessels for operational underway measurements,
continuous surface temperature/salinity measurements are usually obtained
with the thermosalinograph. These data have value in adding to the in-situ
reference data base for surface temperatures, but it is important for
operational use that the data are transmitted to shore at least daily. An
increasing number of vessels also deploys XBT probes now routinely when
steaming on long sections or in transit. This provides more valuable
temperature profiles. Depending on need, funding, and watch schedule of the
crew, the probes are launched 2-4 times per day, and exceptionally every
few hours. For ships steaming at 10 knots, this gives a horizontal spacing of
50-200km.
Strengths and weaknesses:
Research vessels are extremely expensive, and most cruises have a length
of 2-4 weeks. Thus it is not realistic to use such ships purely for operational
routine measurements. When a ship is on the way for another purpose,
however, measurements that do not require stops or extra labour can be
collected nearly for free.
The advantage of these vessels is that they often go to remote areas
where no other in-situ observations are available. A drawback is the lack of
regularity, since most research ships do not routinely go along the same
sections (an exception are Antarctic supply ships).
Further readings: Routine research vessel website.
UWE SEND
2.3.1 Research Vessels
Description:
Research vessels are still the backbone for much of ocean research. Ships
are usually needed to deploy heavy or big instrumentation (geophysical
equipment, moorings, nets) or to collect samples for chemical and biological
analyses. These are very important applications, but the vessels are not
suited for routine, frequently repeated, operational observations – they are
very expensive and e.g. the one-time survey of the oceans with hydrographic
sections under the WOCE program took 10 years! An exception is the use of
research vessels as “ships of opportunity”, where they are used to collect
underway samples as they go to remote and ill-sampled areas for other work.
The instrumentation used then are XBTs (expendable, free-falling
temperature probes), thermosalinographs analyzing water pumped into the
ship from near the surface, and Acoustic Doppler Current Profilers (ADCP)
built into the hull of the vessels.
Application:
When using research vessels for operational underway measurements,
continuous surface temperature/salinity measurements are usually obtained
with the thermosalinograph. These data have value in adding to the in-situ
reference data base for surface temperatures, but it is important for
operational use that the data are transmitted to shore at least daily. An
increasing number of vessels also deploys XBT probes now routinely when
steaming on long sections or in transit. This provides more valuable
temperature profiles. Depending on need, funding, and watch schedule of the
crew, the probes are launched 2-4 times per day, and exceptionally every
few hours. For ships steaming at 10 knots, this gives a horizontal spacing of
50-200km.
Strengths and weaknesses:
Research vessels are extremely expensive, and most cruises have a length
of 2-4 weeks. Thus it is not realistic to use such ships purely for operational
routine measurements. When a ship is on the way for another purpose,
however, measurements that do not require stops or extra labour can be
collected nearly for free.
The advantage of these vessels is that they often go to remote areas
where no other in-situ observations are available. A drawback is the lack of
regularity, since most research ships do not routinely go along the same
sections (an exception are Antarctic supply ships).
Further readings: Routine research vessel website.