Expressions of Intent for IPY 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Getting the timing right: a co-ordinated approach to radiocarbon dating in the Antarctic  (Antarctic radiocarbon dating)

Outline
Sequences of marine sediment containing organic material have a non-zero radiocarbon (14C) age at their tops. This is usually held to be a consequence of the fact that ocean waters contain CO2 out of equilibrium with the atmosphere, on account of the long residence time of carbon dioxide in deep ocean waters. This offset from the true age is known as the marine reservoir effect (MRE). The MRE occurs in most marine samples around the world but the magnitude (>1000 yrs) and variability of the effect is greatest in Antarctica because of the long residence times of CO2 in ocean waters there. Very little is known about the spatial and temporal variation of the MRE around Antarctica. Radiocarbon dating underpins virtually all studies of past environmental change within the timescale of c. 40 ka to the 20th Century. Therefore the large magnitude and variability of the MRE causes enormous problems for environmental research in Antarctica. Whereas in other parts of the world chronologies of past environmental change can be correlated to within a few hundreds of years, in Antarctica it is difficult to achieve correlations even at a sub-millennial scale in the marine environment. This means that no matter how good the records of environmental change are (e.g. high resolution, multi-proxy) they cannot be robustly correlated within or beyond Antarctica. There have been various attempts to estimate the Antarctic marine reservoir effect but all have suggested that the database is currently too small to be able to constrain the significant spatial variability around Antarctica. We propose here an international co-ordinated approach to the problem under the umbrella of the IPY. We have 4 primary objectives: (1) Quantify spatial and seasonal variations in 14C concentrations in sediments being delivered to the modern marine environment; (2) Quantify spatial variation in Antarctic MRE for seabed sediment; (3) Determine spatial variability in MRE for marine organisms found in coastal deposits, and thus extend pre-bomb MRE database; (4) Determine temporal variability in MRE. To achieve these we will collect marine sediment samples from around the Antarctic (using sediment traps and sediment cores), and museum specimens of pre-1950s (pre-bomb testing) marine shells/bones. These will be analysed for the radiocarbon within them in order to better understand the spatial variability of the MRE. These analyses will include new approaches such as isolation of specific molecules that will help us understand the pathways of radiocarbon reaching the marine environment.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
Difficulties with radiocarbon dating severely restrict a wide variety of Antarctic palaeo-environmental research. We propose here an international, co-ordinated approach to the problem that should improve our understanding of marine radiocarbon dating in the Antarctic. By allowing more accurate, robust radiocarbon dating our research will benefit the large number of studies of past and ongoing environmental change that are underpinned by a need for accurate chronologies. This project will therefore benefit those studies seeking to understand rates of current change (IPY Theme 1); the Timing of Past change - essential if we are to understand mechanisms of change - (IPY Theme 2); and allow us to make more robust comparison to records of past change elsewhere (IPY Theme 3).

What international collaboration is involved in this project?
Collaborating institutions in UK, USA (approaches being made to potential collaborators in Australia, Japan, France, Italy, Korea, China, Spain, Scandinavia)

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
Circum-Antarctic marine environment

Approximate timeframe(s) for proposed field activities:
Arctic: n/a
Antarctic: 10/07 – 05/08      10/08 – 03/09      

Significant facilities will be required for this project:
The project will require deployment/retrieval of sediment traps and retrieval of sediment cores, but these will not require dedicated cruises. Rather, we anticipate these activities taking place on existing science cruises that are going to the regions of interest (the precise location of our samples is not important). Therefore our project is well-suited to sharing logistics with other projects, IPY or otherwise.

Will the project leave a legacy of infrastructure?
No

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

As noted in 2.3 above, the project will require some time on existing science cruises, run by various national operators.

Has the project been "endorsed" at a national or international level?
The project has been submitted to UK national representative (JC Ellis-Evans) and will be considered by national committee in Jan-Feb 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?
Yes
This is a new proposal that aims to use the umbrella of the IPY to co-ordinate a series of applications to national funding agencies, addressing a single aim.

How will the project be organised and managed?
The project will be run by a small steering committee. Detailed science management of the project will be driven via a series of collaborative international workshops. At these we will determine the sites and protocols for sampling (pre-IPY), data analysis, and final data collation and interpretation (during and post-IPY).

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
EOC activities still being discussed.

What are the initial plans of the project to address data management issues (as outlined in the Framework document)?
All data will be provided publicly via web-based MRE database for the circum-Antarctic (searchable by area, material, sample type, investigator, lab etc) – possibly as part of the existing Calib 4.4 website (run by one of Co-Is on the project). Peer-reviewed papers outlining results of study and guidelines on obtaining, interpreting and reporting Antarctic radiocarbon dates.

How is it proposed to fund the project?
The project will be funded in two ways: (i) national funding agencies will be approached for money to fund sediment traps, radiocarbon analyses and science workshops(ii) national operators will be approached for logistical support on existing science cruisesThese applications will be co-ordinated by the different national representatives within the project.

Is there additional information you wish to provide?
We emphasise that the results of this study will be useful to an enormous range of palaeoenvironmental researchers, from many nations, and will encompass the entire circum-Antarctic.

PROPOSER DETAILS

Dr Mike Bentley
University of Durham Department of Geography
South Rd
Durham
DH1 3LE
UK

Tel: +44-191-334-1859
Mobile:
Fax: +44-191-334-1801
Email:

Other project members and their affiliation

Other Information