The AMT programme undertakes biological, chemical and physical oceanographic research during the annual return passage of the RRS James Clark Ross between the UK and the Falkland Islands or the RRS Discovery between the UK and Cape Town, a distance of up to 13,500 km. This transect crosses a range of ecosystems from sub-polar to tropical and from euphotic shelf seas and upwelling systems to oligotrophic mid-ocean gyres.
Through the security of OCEANS 2025 funding the AMT programme is now entering its third phase. This will extend the series of research cruises until at least 2012, and will begin with AMT18 scheduled to leave the UK in September 2008. The programme is hosted by Plymouth Marine Laboratory and 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.
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 led to several important discoveries concerning the identification of oceanic provinces, validation of ocean colour algorithms, distributions of picoplankton, identifying new regional sinks of pCO2 and variability in rates of primary production and respiration.
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 objectives included the determination of how 1) the structure, functional properties and trophic status of the major planktonic ecosystems vary in space and time; 2) physical processes control the rates of nutrient supply to the planktonic ecosystem and 3) atmosphere-ocean exchange and photodegradation influence the formation and fate of organic matter. The data collected will be distributed for use in the development of models to describe the interactions between the global climate system and ocean biogeochemistry.
Between 1995 and 2005, the programme has included 17 research cruises, involving ~180 scientists from 11 countries, and has contributed to 110 refereed publications and 68 PhD. Theses. This unique spatially extensive decadal dataset continues to be deposited and made available to the wider community through the British Oceanographic Data Centre.
The last AMT cruise (AMT19) left the UK on 14 October 2009 and arrived in Punto Arenas, Chile at the beginning of December 2009. AMT20 will be leaving Southampton on 12th October 2010.