About AMT

The main deliverable of AMT is a unique time series (1995 - 2023) of spatially extensive and internally consistent observations on the structure and biogeochemical properties of planktonic ecosystems in the Atlantic Ocean that are required to validate models addressing questions related to the global carbon cycle.

The programme is coordinated and led by Plymouth Marine Laboratory in collaboration with the National Oceanography Centre and is now funded by the Natural Environment Research Council's National Capability, having previously received funding through NERC's Oceans 2025 programme as a Sustained Observatory within Theme 10 (which secured the continuation of these measurements along the transect for 5 cruises between 2008 to 2012.)

Biochemical Argo float




research institutes


significant scientific papers


PhD students

AMT Route




First cruise between UK and the Falkland Islands


The programme restarted funded by a NERC Consortium Grant


AMT was funded through NERC's Oceans 2025 programme


NERC CLASS programme continues funding

AMT began in 1995, with scientific aims to assess mesoscale to basin-scale phytoplankton processes, the functional interpretation of bio-optical signatures and the seasonal, regional and latitudinal variations in mesozooplankton dynamics. The programme provided a platform for international scientific collaboration, including the calibration and validation of SeaWiFS measurements and products. The measurements of hydrographic and bio-optical properties, plankton community structure and primary production completed on the first 12 transects (1995-2000) represent the most coherent set of repeated biogeochemical observations over ocean basin scales. This unique dataset has lead to several important discoveries concerning the identification of oceanic provinces, validation of ocean colour algorithms, distributions of picoplankton, the identification of new regional sinks of carbon dioxide and variability in rates of primary production and respiration.

AMT Beginnning

In 2002, the programme restarted (2002-2006) and broadened, to address a suite of cross-disciplinary questions concerning ocean plankton ecology and biogeochemistry and their links to atmospheric processes. The programme was funded by a NERC Consortium Grant and its objectives included the determination of how:

  • The structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time;
  • Physical processes control the rates of nutrient supply to the planktonic ecosystem and;
  • Atmosphere-ocean exchange and photodegradation influence the formation and fate of organic matter.

Between 2008-2012 AMT was funded through NERC's Oceans 2025 programme. This began with AMT18 which took place in October-November 2008. The programme is now in it's fourth phase with funding from NERC's National Capability. The programme is hosted by the Plymouth Marine Laboratory in collaboration with the National Oceanography Centre. It provides an exceptional opportunity for nationally and internationally driven collaborative research and provides a platform for excellent multi-disciplinary oceanographic research. As an in situ observation system, AMT informs on changes in biodiversity and function of the Atlantic ecosystem during this period of rapid change to our climate and biosphere.