Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

U.S. GEOTRACES: Biogeochemical cycles of trace elements in the SW Pacific Sector of the Southern Ocean  (U.S. GEOTRACES in the Southern Ocean)

Outline
The Southern Ocean plays a key role in the global carbon cycle. Recent studies have demonstrated that phytoplankton physiology, ecosystem structure, and the efficiency of nutrient utilization in the Southern Ocean are influenced by the availability of trace elements that serve as micronutrients (e.g., iron, cobalt, zinc). This, in turn, influences the efficiency of CO2 sequestration in the deep sea. Consequently, a high priority for research in the Southern Ocean is to identify the physical and biogeochemical processes that regulate the supply of micronutrients to phytoplankton, and to combine that effort with a characterization of the biological response to changes in micronutrient supply. This information is vital for predicting the impact of climate variability and future environmental change on marine biodiversity and the ocean carbon cycle. The community of marine biogeochemists is developing a new international research initiative (the GEOTRACES program) that aims to identify, characterize and quantify processes that control the distribution of key trace elements and isotopes (TEIs) in the global ocean and their sensitivity to changing environmental conditions. Doing so will elucidate the supply of micronutrients to phytoplankton, contaminant dispersal in the ocean, and tracers of past and present ocean conditions. This initiative is prompted by the increasing recognition that TEIs are playing a crucial role as regulators and recorders of important biogeochemical and physical processes that control the structure and productivity of marine ecosystems, the dispersion of contaminants in the marine environment, the level of greenhouse gases in the atmosphere, and global climate. With international cooperation, the GEOTRACES program will carry out high-resolution sampling along three water column sections, corresponding roughly to the “choke points” separating the three sectors of the Southern Ocean: (1) an international program (BONUS) on a French vessel studying together the South African margin/upwelling effect on water masses and the GoodHope/CLIVAR section down to 50°S, 0°W, (2) an international program aboard the Polarstern (German research vessel) connecting with the BONUS transect along 0°W and also working across the Drake Passage, and (3) a US study between New Zealand and Antarctica. This proposal pertains to the last of these three sections. Trace elements targeted for study can be subdivided into four categories: 1) Micronutrients (e.g., Fe, Co, Zn, Cu); 2) Tracers of micronutrient source (e.g., Al, Mn, Nd isotopes, rare earth elements); 3) Tracers of the internal cycling of micronutrients and of their rates of removal from the water column, (e.g., particle-reactive natural radionuclides); and 4) Tracers of past changes in ocean conditions that can be extracted from marine sediments, including TEIs derived from each category above. Complementary measurements will characterize the biological response to varying supply of micronutrients; e.g., pigment concentrations to determine the relative abundance of different phytoplankton taxa and fast repetition rate fluorometry to establish the physiological state of the dominant taxa.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
Theme 1-Present environmental status: This multidisciplinary study will establish the interplay of physical and geochemical processes that regulate the supply of essential micronutrients to polar marine ecosystems, with implications for the physiological state (health) of these ecosystems, their spatial and temporal patterns of variability, and their impact on carbon storage and export to the deep sea. Theme 2-Understand past changes: Trace elements contained in marine sediments provide important information about past changes in ocean circulation, biological productivity and carbon fluxes. Ground-truthing of existing geochemical paleoceanographic proxies and development of new ones specifically for the Antarctic environment will improve our understanding of past changes in this sensitive region. Theme 3-Links to other regions: Processes in the Southern Ocean regulate the supply of nutrients to tropical ocean regions (impacting fisheries) and the concentration of CO2 in the atmosphere (impacting climate). The sensitivity of these processes to the availability of trace elements (micronutrients) will be established. Theme 4-Frontiers: A complex interplay of physical and chemical conditions influences the unique character of polar marine ecosystems. This work provides an essential component of an interdisciplinary study that will establish the sensitivity of polar marine ecosystems to changing environmental conditions, and the implications for global biogeochemical cycles of carbon and related substances.

What international collaboration is involved in this project?
GEOTRACES is an international project under development, which has been initiated by an international consortium of scientists (Organizing Committee: R. Anderson, USA; R. Francois, Canada; M. Frank, Switzerland/Germany; G. Henderson, UK; C. Jeandel, France.

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
US GEOTRACES will work in the SW Pacific sector of the Southern Ocean, along a transect between New Zealand and the Ross Sea occupied previously by the WOCE, JGOFS-AESOPS, and SoFeX programs. Reoccupying a section studied by earlier programs will provide valuable information about interannual variability, and its relationship to climate (e.g., ENSO and the Antarctic Oscillation).

Approximate timeframe(s) for proposed field activities:
Arctic: n/a
Antarctic: 3/07 – 3/09            

Significant facilities will be required for this project:
Ice-breakers, ice strengthened research ship, remotely operated vehicles, satellites. Dedicated trace-metal clean facilities aboard ships, including rosettes, winches, and lab vans.

Will the project leave a legacy of infrastructure?
GEOTRACES will develop new technologies for sampling and analysis of seawater for trace elements and isotopes (e.g., see separate EoI submitted by GEOTRACES investigators in Germany and the Netherlands), but will not leave infrastructure deployed in the ocean upon completion of the program. GEOTRACES will produce an archive of water samples to serve future investigations that may not have ready access to remote areas of the Southern Ocean.

How is it envisaged that the required logistic support will be secured?
Consortium
Own national polar operator
Another national polar operator
National agency

Has the project been "endorsed" at a national or international level?
This proposal will be submitted to the US IPY committee, but that committee will not endorse individual proposals. Approval of the international GEOTRACES Science Plan by SCOR and ICSU is anticipated during Summer 2005.

PROJECT MANAGEMENT AND STRUCTURE

Is the project a short-term expansion (over the IPY 2007-2008 timeframe) of an existing plan, programme or initiative or is it a new autonomous proposal?
Exp

This project will be an integral part of the international GEOTRACES program, which aims to conduct a global study of the marine biogeochemical cycles of trace elements and their isotopes. Approximately 200 scientists from at least 15 nations have participated in GEOTRACES planning activities to date.

How will the project be organised and managed?
The national GEOTRACES committees will work in close association with the international GEOTRACES Scientific Steering Committee, which will oversee an International Program Office (IPO) and a Data Management System.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
One of the central objectives of the GEOTRACES program is education, building and maintaining a core community of marine scientists who understand and are able to integrate the chemical, physical and biological processes regulating the distribution and properties of TEIs well enough to exploit them reliably in future interdisciplinary studies. Outreach and communication will be conducted through various media outlets, internet, brochures and by promoting school participation through interactive distance learning websites. The Southern Ocean “Iron Hypothesis” has received substantial public attention, and will be used as a centerpiece for engaging widespread interest in our public outreach efforts.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
Data management for this project will be handled through the international GEOTRACES Data Assembly Center under the supervision of a Data Management Committee, which will handle data from all countries participating in the GEOTRACES program.

How is it proposed to fund the project?
GEOGEOGEOTRACES- will seek funding from appropriate national funding programs.

Is there additional information you wish to provide?
The US GEOTRACES Southern Ocean study will be planned and coordinated in the context of global GEOTRACES program, which includes work in both polar regions (see GEOTRACES IPY ”umbrella” EoI). Other key contributions to GEOTRACES work in the Southern Ocean include international expeditions aboard French (BONUS) and German (ZERO& DRAKE) vessels. GEOTRACES research in the Southern Ocean will be integrated with complementary physical and biological studies (e.g., CLIVAR/ GoodHope, iAnZone/SASSI, SCACE) under the supervision of the CASO (Climate in Antarctica and the Southern Ocean) umbrella.

PROPOSER DETAILS

Dr Robert Anderson
Lamont-Doherty Earth Observatory
P. O. Box 1000
Palisades, NY
10964
USA

Tel: +1 845 365 8508
Mobile: no
Fax: +1 845 365 8155
Email:

Other project members and their affiliation