NOAA Oceanic & Atmospheric Research | Climate Portal | Climate Program Office | Climate Observation Division


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How We Observe the Ocean

Ocean Reference Stations

Sustained time-series of oceanic and atmospheric climate-relevant parameters and air-sea exchange of heat, freshwater and carbon dioxide are central to documenting and understanding trends and variability in the climate system. To this end NOAA, together with international partners, has implemented a global array of heavily-instrumented moored buoys to provide the most accurate possible long-term climate data records of oceanic and near-surface atmospheric parameters in key ocean regimes. The National Science Foundation’s Ocean Observatories Initiative will provide a major piece of the infrastructure needed for this network, establishing high-capability moored stations, particularly in high latitude ocean locations. These ocean reference stations provide globally-distributed, high-quality, continuous datasets that can also be used to detect sudden changes and events, to calibrate remotely sensed measurements, to elucidate climatically sensitive processes, and to evaluate and improve models.


  • Ocean Reference Station Details
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Different ocean reference stations are instrumented to monitor different portions of the full suite of physical and biogeochemical variables that characterize the local ocean environment. Moored buoys that carry meteorological sensors to characterize the exchanges of heat, momentum, freshwater, and gases (e.g., carbon dioxide) across the air-sea interface are referred to as air-sea "flux" stations. These moorings also generally carry sensors on their anchor line to monitor the physical and sometimes biogeochemical environment in the upper ocean. Other moorings, referred to as "observatories," are designed primarily to monitor the biogeochemical properties within much of the water column, while "transport" stations, monitor ocean currents and transport.

NOAA’s contribution to the international network of ocean reference stations includes stations in tropical regions, where a subset of the tropical moored buoy array (TAO/TRITON, PIRATA, and RAMA) has been upgraded to reference station quality, as well as several other long time-series sites focused on measurement of air-sea fluxes. Additional long-term monitoring to measure the primary routes of ocean transport is sustained at key choke points such as the Indonesian through-flow, while continental boundary currents such as the California Current are observed to monitor changing climate regimes that strongly impact fisheries and ecosystems. In addition, a special set of sustained observations is necessary to document trends and variability in the ocean’s meridional overturning circulation to elucidate the role of the ocean in rapid climate change. To this end, long-term measurements are made at a few critical locations from bottom-mounted and subsurface moored arrays, complemented by repeated temperature, salinity, and tracer surveys from research vessels.

The Ocean Reference Station global effort is coordinated by the JCOMM-affiliated OceanSITES (Ocean Sustained Interdisciplinary Timeseries Environment observation System) program, and is one of the most challenging networks to implement because of the expense of maintaining highly accurate instruments in remote ocean regions. Uniform data standards are set by the OceanSITES community, which maintains global data assembly centers at the NOAA National Data Buoy Center and the French Research Institute for Exploitation of the Sea (IFREMER).