Robinson, Carol, Manuel Barange and the AMT team

Plymouth Marine Laboratory, Prospect Place, West Hoe, Plymouth. PL1 3DH. UK, Tel: +44-1752-633462, Fax: +44-1752-633101, E-mail: carol.robinson@pml.ac.uk

The Atlantic Meridional Transect Programme

The Atlantic Meridional Transect (AMT) Programme (1995-2006) [http://www.pml.ac.uk/amt/] aims to quantify the nature and causes of ecological and biogeochemical variability in the planktonic ecosystems of the Atlantic Ocean, and the effects of this variability on biological carbon cycling and air-sea exchange of radiatively active gases and aerosols. Marine and atmospheric data are collected from more than 14 biogeochemical provinces between the UK (50^oN) and the Falkland Islands (52^oS) including the undersampled subtropical gyres and the NW African upwelling.

Twelve cruises have taken place since 1995 involving 80 scientists from 10 countries collecting measurements of 31 determinands. These data represent the most coherent set of repeated biogeochemical observations over ocean basin scales and have led to several important discoveries concerning the validation of ocean colour algorithms, and the seasonal, inter-annual and latitudinal distributions of pCO₂, picoplankton, and rates of primary production and respiration.

Funding from the UK Natural Environment Research Council (NERC) will enable six further cruises to take place during 2003 – 2005 in order to 1) determine how the structure, functional properties and trophic status of the planktonic ecosystems vary in space and time, 2) determine the role of physical processes in controlling the rates of nutrient supply to the planktonic ecosystem and 3) determine the role of atmosphere-ocean exchange and photo-degradation in the formation and fate of organic matter.

This presentation will summarise the results obtained thus far and describe the future hypotheses to be tested.