The oceans are very sparsely sampled in space and time, yet many fundamental questions of both scientific and practical importance depend on understanding change and variability at time-scales from days to decades, and from local to regional to global scales.
No single measurement technique can provide all the information needed to build a complete picture of the complex nature of our oceans. For example, while satellites give good spatial coverage of the oceans, the time resolution is usually low (many days between satellite passes) and space-borne instruments measure only the surface skin of the sea. Likewise, instruments moored to the sea-floor and so located at fixed points in space can give very detailed information about changes in time at these locations, but such instrument moorings are very expensive and so are found in very few locations in the oceans. Drifting buoys and opportunistic use of commercial ships help fill data gaps, but have their own limitations.
Listed below are some of the different ways in which scientists gather data from our oceans. Specific programmes that the NOC and its partners have, and are, contributing to are listed under each:
An important priority for the future is to reduce the dependence of oceanographers on expensive research ships for the more routine long-term measurements. There is increasing focus on autonomous vehicles with which we hope to increase the spatial and time density of sampling in the oceans. The NOC is contributing towards the development of multiple new technologies (visit our technology section for more information).
- Satellites and aircraft – surface measurements over wide areas.
- Moored buoys and observatories – detailed measurements at fixed locations.
- Drifting buoys and profiling floats – subsurface measurements of a few parameters at many locations using instruments such as ARGO floats.
Repeat sections – repeated detailed measurements across extended transect lines of the ocean (sometimes sea surface to sea floor and from coast to coast across an entire ocean basin by research ship).
- Extended Ellett Line
- RAPID-WATCH Repeat Sections
- Antarctic Circumpolar Current Drake Passage Section
- Atlantic Meridional Transect
- Ships of opportunity – surface measurement of a few parameters from commercial cargo and passenger ships to improve spatial coverage.
- Coastal sampling – measurements that can be made from the coast - coastal sea level, temperature, shore dwelling marine plants and animals.
An important priority for the future is to reduce the dependence of oceanographers on expensive research ships for the more routine long-term measurements. There is increasing focus on autonomous vehicles with which we hope to increase the spatial and time density of sampling in the oceans. The NOC is contributing towards the development of multiple new technologies - visit our Technology section for more information.