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Major research mission back on track after three year hiatus

21 February 2023

The Atlantic Meridional Transect (AMT) is a research programme that samples the open ocean between the UK and the South Atlantic, and it is readying for departure after a COVID enforced pause.
Sampling on AMT29. Image: Dr Gavin Tilstone
Sampling on AMT29. Image: Dr Gavin Tilstone
This week we are very excited that AMT30 will be leaving the Falkland Islands for its 38-day voyage back to the UK; the first AMT expedition to run since 2019.

AMT30 waiting for departureThis research cruise, led by Plymouth Marine Laboratory (PML) and funded by Natural Environment Research Council's (NERC) National Capability, is a highly important expedition for the marine science community as it collects samples along the length of the Atlantic, producing a unique dataset and the opportunity to monitor changes in this expansive and dynamic ocean.

It also provides an invaluable training experience for budding marine scientists to work at-sea alongside leading researchers from around the world.

AMT is a truly multidisciplinary programme that undertakes biological, chemical and physical oceanographic research during the usually annual voyage between the UK and destinations in the South Atlantic.

The main deliverable of AMT is the unique data time series (1995 – 2019 and now 2023) of spatially extensive and consistent observations on the structure and biogeochemical properties of planktonic ecosystems in the Atlantic Ocean. This data is vital to validate models addressing questions related to the global carbon cycle as well as monitoring environmental change.

Planned AMT30 trackAMT30 will leave Port Stanley on 21st February 2023 aboard the RRS Discovery, which will be home for over six weeks to crew and 26 scientists from PML, Scottish Association for Marine Science, National Oceanography Centre (NOC) and the Universities of Oxford, Exeter, Liverpool, East Anglia and Heriot Watt. We also welcome guests from University of Lisbon (Portugal), Michigan State University and NASA (USA), University of Pretoria (South Africa) and the Center for Scientific Research and Higher Education in Ensenada (Mexico).

The AMT missions always have a packed science agenda and this year is no exception. Sampling activities will include:
  • Carbon chemistry
  • Microbial biodiversity
  • Nutrient distribution
  • Nitrogen fixation
  • Optical properties
  • Oxygen status
  • Gas exchange
  • Aerosol deposition
  • Zooplankton diversity
  • Particle export
NASA are once again joining PML scientists to help ‘sea-truth’ their satellite sensors, with AMT providing a unique opportunity to validate and calibrate their optical equipment in the remote ocean, far from human interference.

This year also sees a return of the POGO Special Visiting Fellow for Shipboard Training from the Center for Scientific Research and Higher Education in Ensenada (CICESE), Mexico. The selected Fellow, Yessica Pacheco, has spent two weeks at NOC prior to the cruise to join in with preparation and planning. At sea she will join the AMT team in hydrological, bio-optical and ecological observations and after the cruise, she will then spend another month at NOC learning to analyse and interpret the measurements she has made.

Dr Andy Rees, Marine Biogeochemist at PML and lead scientist for AMT, commented on the research mission: “AMT is a fantastic opportunity to get marine scientists into the remote ocean gyres and it is one of very few opportunities to do so. AMT30 provides continuation of our measurements since 1995 so we are now getting towards a position where we are able to detect decadal scale changes in this vast ecosystem.”

“Our research activities are key to understanding how biodiversity and biogeochemical cycles function naturally and indicates how they might be influenced by climatic change and ecosystem variability. Whilst our scientific activities are hugely rewarding the most challenging aspect of such a long mission is being away from home and separation from family and friends”.

The AMT dataset, hosted by the British Oceanographic Data Centre, has had over 240,000 downloads and has generated over 380 scientific publications.

Founder of AMT, Prof. Jim Aiken who is an Emeritus Fellow at PML, commented: “As the research programme approaches its 30th year, I am extremely proud that this important dataset continues to grow and provide such vital information to marine scientists around the world, to help improve understanding of the Atlantic Ocean, it’s processes and how it is changing. The co-ordination teams and participants over the years have all contributed to making this valuable scientific programme the success it is and the dedication of the current team in keeping the programme running is most commendable. Long may AMT continue!”.

In addition to AMT30 itself and due to the vagaries of travel to such a remote location, a number of the PML team will arrive in the Falkland Islands several days before joining the RRS Discovery. They will make the most of this opportunity by connecting up with colleagues from the UK Centre for Ecology & Hydrology and the South Atlantic Environmental Research Institute and collect samples from several Falkland estuaries. This work will complement PML’s NERC-funded AgZero+ project by making measurements of dissolved greenhouse gases and their fluxes to the atmosphere in this pristine environment, which receives little pressure from human activities.

Follow AMT30 on Twitter.

Related information

Atlantic Meridional Transect (AMT)