Table 7. Technologies
TECHNOLOGYADVANTAGESDISADVANTAGES
Research VesselsMost flexible platform available.
Variety of measurements possible.
Expensive.
Cannot provide synoptic coverage easily.
Ships of OpportunityPotential wide spatial and frequent temporal coverage.
Inexpensive.
Difficult logistics.
Quality control problems.
AircraftGood spatial coverage in selected regions. Expensive.
Limited by weather.
Limited instrument types and numbers
Focus on nearŠsurface observations.
SatellitesSynoptic, good spatial coverage, reasonably good temporal resolution.
Low operating costs.
Good for sea-level, temperature, pigments and winds.
High initial cost.
Long-term stability in question.
Clouds cause problems.
Some sensors not useful near shore (within 50 km).
Limited to near-surface conditions.
MooringsHigh temporal resolution.
Capable of handling many different types of sensors incl. physical, bio-optical, acoustical, meteorological.
Low spatial resolution except in the vertical dimension.
High cost.
Difficult to maintain on fishing grounds.
DriftersFollow water mass (Lagrangian).
Can provide ancillary physical and bio-optical data.
Potential for instrument loss.
High cost for heavily instrumented versions.
EŠM Cable VoltagesLow operating cost.
Low maintenance.
Provide estimates of spatially integrated transport.
Good for long-term sampling.
High initial cost if new cable required.
Difficult to use in regions with fishery operations.
Calibration required.
AcousticsMature technology with many different sensor options.
Measure abundance, size-frequency distribution and currents (ADCP).
High vertical resolution.
Rarely provide species identification.
Boundary interference.
OpticsVarious technologies of varying capability available including Video Plankton Recorder (VPR), Optical Plankton Counter (OPC), absorption meters, Lidar.
Some can provide taxa identification.
Some can be deployed on moorings or drifters.
Can estimate standing stock of autotrophs and small heterotrophs.
More advanced systems, such as VPR are not mature, not readily available and not cheap.
Less expensive technologies (OPC) provide size structure, but not taxa identification.
Short range.
Molecular and Biochemical MethodsCan be used to evaluate physiological condition, diet, stock structure, species identification and perhaps age of target organisms.Development of techniques.
Labor intensive, but potential for automation and use of robotics.
Historical ProxiesTree rings, sediment cores, cold water corals, forams and isotopic scale analysis might provide timeŠseries records of atmosphere, ocean or ecosystem conditions.Lots of exploratory work needed.
Calibration of some techniques difficult.
Provide no recent information.
Smart TagsCan be used to describe animal behavior, geographic position, migration patterns, and monitor physiological condition.
Already proven useful for some fish and many marine mammals.
Potentially low return rates.
Need to keep the tags inexpensive.
Only applicable to larger organisms.