Understanding Trace Elements and Isotopes in the Ocean: A GEOTRACES Workshop

2. Outline of Introduction Presentation Timeline Motivation for the GEOTRACES programme Status of GEOTRACES Goals of this workshop Format of the workshop

3. GEOTRACES guiding mission To identify processes and quantify fluxes that control the distributions of key trace elements and isotopes (TEIs) in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions. Mission

4. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

5. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

6. Iron as a limiting nutrient in HNLC regions

7. Iron as a limiting nutrient in HNLC regions

8. Input fluxes of bioactive metals

9. Present ignorance: Existing deep ocean Fe data DataLimited for Fe Paucity of information about deep Fe distribution limits understanding of upwelling supply and internal cycling. Stations with Fe concentrations at depths > 2000 m. As of 2003. From P. Parekh (MIT)

10. Models are based on limited data… DataLimitsModels Model of Fe cycle(Parekh et al. 2005) Model of ecosystem limitation(Moore et al, 2004)

11. Iron is not the only trace metal crucial for ocean biology Other essential TEIs Figure from F. Morel

12. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

13. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

14. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

15. Ignorance about cycling of trace elements

16. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

17. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

18. Paleoclimate indicates behaviour of climate system

19. The need for proxy calibration Two proxies for rate of NADW flow agree that flow is strong in Holocene, but disagree about strength of flow at LGM and during deglaciation

20. What are “key” elements? • They include: • Those acting as micronutrients to control ocean productivity and ecosystems • Those tracing modern processes in the ocean • Contaminants in the present and future ocean • Chemical species used as proxies to reconstruct past climate Mission

21. Substantial interdisciplinary benefits of disciplinary study of ocean geochemistry Now 30 years since last global program in marine geochemistry (GEOSECS) Improved ability to sample the ocean without contamination Increased sensitivity of analytical instrumentation Advances in modeling permit rates and fluxes to be derived from modeling Timeliness

22. Science Plan Published in late 2006 Download PDF from http://www.geotraces.org/ Or hard copies available here (also substantially replicated in Chemie de Erde paper in your workshop folders)

23. Enabling Activities Standards and intercalibration Data protocols, management, archiving Modeling Test stations Ocean Sections Core activity - requires international cooperation 12-15 sections Covering regions dominated by major processes National cruises with international collaboration Process Studies Targeted at processes known to be important Targeted at “anomalies” detected in ocean sections Some will focus on ocean boundaries (e.g., coastal regions) Some will exploit time-series stations Program Elements (Implementation)

24. Nations involved in planning USA UK Japan Canada France China Mexico Germany Australia Brazil Netherlands India Chile Sweden Korea Peru Spain Taiwan Belgium New Zealand Hong Kong

25. GEOTRACES - Scientific Steering Committee (SCOR) Bob Anderson, Lamont-Doherty Earth Observatory, USA, Co-Chair Gideon Henderson, University of Oxford, UK, Co-Chair Per Andersson, Swedish Museum of Natural History, Sweden Philip Boyd, University of Otago, New Zealand Ken Bruland, University of California Santa Cruz, USA Minhan Dai, Xiamen University, China Hein de Baar, Netherlands Institute for Sea Research, The Netherlands Martin Frank, IfM-GEOMAR, Germany Toshitaka Gamo, The University of Tokyo, Japan Catherine Jeandel, LEGOS (CNRS/CNES/IRD/UPS), France Bill Jenkins, Woods Hole Oceanographic Institution, USA Pere Masque, Universitat Autonoma de Barcelona, Spain Chris Measures, University of Hawaii at Manoa, USA Felipe Niencheski, Fundaco Universidade Federal do Rio, Brazil Kristin Orians, University of British Columbia, Canada James Orr, International Atomic Energy Agency, Monaco Carol Robinson, Plymouth Marine Lab, UK Michiel Rutgers van der Loeff, Alfred Wegener Institute, Germany Reiner Schlitzer, Alfred Wegener Institute, Germany Sunil Kumar Singh,Physical Research Laboratory, India Jing Zhang,University of Toyama, Japan SSC <www.geotraces.org>

26. Future timeline Basin Workshops -> Identify Sections & Process Studies June/September/October 2007 Basin plans to be formally approved at next SSC meeting in Nov 2007 Intercalibration and Data-Management protocols being established now First cruises - Intercalibration and IPY cruises planned for 2007/2008 Program completion - Decade-plus timescale Timeline

27. SCHEMATIC (!) ocean sections for GEOTRACES Sections Sections will be designed to investigate regions where targeted processes dominate trace element cycles.

28. Distributions reflect circulation and biogeochemistry AtlanticNitrate Much can be inferred about nutrient cycles from a basic knowledge of ocean circulation and nutrient distribution.

29. Ability to make these measurements for TEIs AtlanticNitrate • Al traces source of Fe • Fe distribution reflects biological uptake and regeneration Unpublished data of Chris Measures and Bill Landing

30. Distributions reflect circulation and biogeochemistry AtlanticNitrate

31. …but existing data are limited in extent Fe (nmol/kg) Atlantic Fe Results from CLIVAR cruises show comparable richness of features in Fe distribution.

32. SCHEMATIC (!) ocean sections for GEOTRACES Sections Sections will be designed to investigate regions where targeted processes dominate trace element cycles.

33. The major goal of this workshop….Identify the sections (and process studies) required to meet the scientific goals of the GEOTRACES programmeProvide justification and rationale for the choice of sections

34. Australia Canada China Japan Korea/Japan New Zealand Taiwan U.S. Hawaii Tahiti Easter Island Proposed Pacific Sections

35. Keynote 1: “Observations and modelling the ocean Fe cycle: Role in the carbon cycle and state of understanding”Ed Boyle (MIT, USA) Keynote 2: “The importance of bioactive trace metals in the marine environment”Mak Saito (WHOI, USA) Keynote 3: “Trace element and isotope proxies: constraints on the carbon cycle”Ros Rickaby (Oxford, UK) Keynotes (Monday)

36. Programme Logistics 1: “Intercalibration of measurements for GEOTRACES”Gregg Cutter (Old Dominion, USA) • Programme Logistics 2: “Data management during GEOTRACES”Chris Measures (Hawaii, USA) Programme Logistics

37. Planned Activities 1: “The BONUS-GOODHOPE IPY Cruise”Marie Boye (LEMAR, Plouzane, France) Planned Activities 2:“AMANDES project” Catherine Jeandel (Kiel, Germany) Planned Activities 3: “Zero and Drake IPY Cruise”Hein de Baar (RNRSI, Netherlands) Planned Activities 4: “Arctic IPY activities”Per Anderson (Swedish Museum of Natural History, Sweden) Planned Activities 5:“Mauretania to the Brazil Basin cruise” Martin Frank (Kiel, Germany) Planned Activities 6: “UK SOLAS work relevant to GEOTRACES”Eric Achterberg (National Oceanography Centre, UK) Planned Activities 7: “German SOLAS work relevant to GEOTRACES”Peter Croot (Kiel, Germany) Planned activities

38. Keynote 4: “A GEOTRACER's perspective of the hydrography and circulation of the Atlantic”Bill Jenkins (WHOI, US) • Advocacy talks • These will set the agenda for the breakout groups that follow • Breakout groups • Will focus on particular regions/questions and define sections and their justification • Plenary sessions • Will report discussion of breakout groups, and finalize plans Remainder of meeting

39. GEOTRACES - Scientific Steering Committee Black Finis Meets 16-18 December in SF. Opportunity for input now!