Atlantic Meridional Transect AMT-18 Malcolm Woodward Plymouth Marine Laboratory

1. Atlantic Meridional Transect AMT-18 Malcolm Woodward Plymouth Marine Laboratory m.woodward@pml.ac.uk RRS James Clark Ross, Cruise JR218 October-November 2008

2. RRS James Clark Ross, Cruise JR218 Phases of the AMT: AMT 1-11, First phase, opportunistic, Ocean colour, NASA funding AMT 12-17, NERC Consortium Grant AMT 18-21?, OCEANS 2025 Core Science Theme 10 – Integration of Sustained Observations (SO) in the Marine Environment Provides infrastructure and scientific co-ordination to support marine time-series and monitoring studies

3. Atlantic Meridional Transect AMT-18 SCIENCE AIM within 2025. “To provide a sustained open ocean in situ observing system to enable early warning of any fundamental change in ecosystem functioning and to better forecast the marine environment for society’s needs” • Effectively plan and undertake one cruise per year • Produce data policy and ensure data delivery to BODC within appropriate time scale • Construct a ‘basin scale observatory’ with web based in situ and data visualization and delivery • Facilitate efficient use of AMT data within Oceans 2025, nationally and internationally • Actively engage in publicity and knowledge transfer • Continue core ecological and biogeochemical measurements • Validate and develop bio-optical algorithms • Comparison of the gyres • Improved physics • Sediment traps mid gyres • Berths available national & international collaborators • Link with time series stations in the Atlantic • SCOR / POGO funding for students from developing countries

4. AMT so far has provided: The most coherent set of repeated biogeochemical observations over ocean basin scales.  The identification of oceanic provinces. Validation of ocean colour algorithms. Unique distribution maps of picoplankton. Identification of regional sinks of pCO2 Variability in rates of primary production and respiration.  Between 1995 and 2005, the programme has included: 17 research cruises, involving ~200 scientists from 11 countries. and has contributed to 132 refereed publications and 69 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 (BODC). AMT Management for OCEANS 2025: Science Head of AMT- Andy Rees, PML. apre@pml.ac.uk Cruise Logistics, BAS Liason/contact: Malcolm Woodward NOC Science co-ordinator: Mike Zubkov

5. RRS James Clark Ross, AMT-18, PAP AMT 18 (OCEANS 2025) cruise track : 1. Immingham 2. E1/L4 of Plymouth. 3. PAP site: (49.00N 16.30’ W) 4. NOG site: (23.46’N 41.06 W) 5. Equator: (00.01S 25.00’ W) 6. SOG site: (15.1S 25.00’W) 7. Southern turn: (28.00S 25.00’ W) 8. Port Stanley: (51.75S 58.00’ W) Our proposed track is 7979 miles, just over 30 days. We have 38 days at sea. DIP Clear for Azores, submitted. NOG SOG

6. Personnel AMT-18 • PSO: Malcolm Woodward, PML • Macro Nutrients: Carolyn Harris, PML • Gavin Tilstone: C14+CDOM, PML • Chris Gallienne: Optics, PML • Glen Tarran: AFC/LiZa, PML • Vas Kitidis: P:R, PML • Ross Holland: AFC, NOC • John Allen, Physics, NOC • Stuart Painter, NOC • Manuela Hartmann, NOC • Martin Ostrowski, Warwick • Mike Zubkov, NOC • John Pearman, Warwick • Martine Coupael, Nat Hist Mus • Jeremy Young, Nat Hist Mus • Paul Mann, Newcastle/PML • Bruce Bowler, Bigelow • SCOR/POGO Fellow • .NMF technician • . NMF technician • .BAS ICT Technician • .BAS AME technician

7. SCIENCE OUTLINE PLANNING: • Pre-dawn CTD (0430 ?), • and a solar noon CTD at approx 1330. • Depth of CTD, ‘normal’ is to 300m but will go to 500m where time permits and if possible some full ocean depths CTD’s. • Pre-dawn Station: • CTD • Zooplankton netting using forward starboard crane/davit • Solar noon Station: • CTD • Optics rig deployed over starboard quarter using crane and away from ships side to avoid shading. • Zooplankton nets forward as pre-dawn. • Moving Vessel Profiler: MVP deployed from port quarter • To be deployed between stations.

8. AMT-18 Scientific cruise Co-ordination/Logistics, single point of contact with the BAS, myself. Co-ordination for paperwork etc, Julia Crocker, jlc@pml.ac.uk NMF cruise manager: Jon Short

9. Profiles – on station • Single optics deployment around solar noon (taking note of the ship’s longitude): ac-9; UV Satlantic sensor; bb6; CTD; FRRF; PAR sensor. • Single deployment with two casts, one with filters and the other without – to give IOP partitioning (duration?). • FRRF requested from NMF– intercomparison with the FiRE and C14 methods of photophysiology Science: Optics on AMT 18 • Continuous underway • Hyperspectral water leaving radiance: cal/val, algorithm dev. • Deck measurements of hyperspectral UV, Vis: reference instruments. • Aerosols: NASA AERONET sunphotometer

10. AMT-18 Incubations Deck Incubations with on-deck sea- water supply, Primary Poduction, CDOM incubations, Ammonia photoproduction 8-10 square metres. Not shielded from sunlight

11. Bow-mounted radiometers

12. Mast-mounted irradiance sensor

13. AMT-18 Other Requirements: 20 Foot ISO radioactive container on aft deck 20 Foot equipment storage container MVP on port quarter Optics rig deployment – we have Kevlar cable, need drum/winch, starboard quarter Atmospheric sampling units from UEA on Monkey island All lab spaces to be free, cold room, chem stores, Fridges, freezers, -20, -80 Items on Cruise Questionnaire