Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Detection of Crystal Orientation Fabrics near the Ross/Amundsen Sea Ice-flow Divide and at the Siple Dome Ice Core Site Using Polarimetric Radar Methods  (Radar Polarimetry in the WAIS)

Outline
We propose to investigate the alignment of crystals in ice, called crystal-orientation fabrics (fabrics), with ground-based radar measurements near the Ross/Amundsen Sea ice-flow divide, West Antarctica, where a deep ice core will be drilled. Fabric has an important effect on ice deformation. As ice deforms, anisotropic fabrics are produced, which, in turn, influence further deformation. When fabric is not rotationally symmetric about a vertical axis, vertically-propagating radio waves are affected by bulk birefringence related to axis orientation of the fabric. Preliminary results show that well-established polarimetric radar methods can detect degree of horizontal anisotropy of fabrics and their orientation, even when they are nearly vertical-symmetric fabrics. To understand secondary effects on radar-echo anisotropy, we also propose to make radar measurements at Siple Dome and study radio wave propagation using fabric information from the ice core there. Inconjunction with polarimetric radar measurements, we will make ice strain measurements with global positioning system (GPS), and radar profiling connecting all sites for polarimetric radar measurements. GPS data together with depth variation of radar-detected isochrones will be used to derive modern strain rate configuration. We will simulate fabrics for shallow depths (~1,000 m) with these strain data. Using the simulated fabrics as a reference, we will examine mismatches between simulated and measured fabric azimuths and strengths, and their horizontal variation to infer possible divide migration in the past. This new method can provide a unique record of ice-deformation history in this region, where little controls are available on its history. This project will host graduate research and provide undergraduate research experiences.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
Measurements of fabric variations can help reveal the deformation history of the ice and indicate how the ice will deform in the future. Ice cores provide opportunities to determine a vertical fabric profile, but horizontal variations of fabrics remain unknown. This project will examine mismatches between ice fabrics inferred from the radar measurements and simulated with the current strain configuration. It gives a unique constraint on the evolution of the inland West Antarctica, and leads to development of new methods with broad applicability in ice sheets and glaciers.

What international collaboration is involved in this project?
A radar system that will be used in this project will be provided by National Institute of Polar Research, Tokyo, Japan.

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
This project will work near the Ross and Amundsen Sea ice-flow divide, inland West Antarctic Ice Sheet, where U.S. Glaciology community plans to drill a deep ice core. Supplemental work will be done at the summit of Siple Dome, in the Ross Sea embayment. We anticipate that U.S. National Science Foundation (NSF) will grant this project and provide logistic support to carry out the field work.

Approximate timeframe(s) for proposed field activities:
Arctic: n/a
Antarctic: Jan, Feb, 2007            

Significant facilities will be required for this project:
Radars (ground-based). Snow terrain vehicles. Fixed wing transport aircraft (C130). Existing field Station (McMurdo). Fuel deposit to support ground traverse.

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
National agency

Has the project been "endorsed" at a national or international level?
PIs have been proposed this project to U.S. National Science Foundation. PIs are involved in the WAISCORE and U.S. WAIS communities.

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?
New

This specific project is new, but it will complement ongoing WAISCORE and WAIS efforts by the U.S. glaciology community.

How will the project be organised and managed?
This project will be managed by PIs at the University of Washington, with close collaboration with U.S. WAISCORE community.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
This project will host graduate research and provide undergraduate research experiences. Web sites will be established to show our activities with general introduction and release our data.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
We will release the obtained data to the research community according to NSF data policy.

How is it proposed to fund the project?
We have been proposed this project responding to a regular research solicitation by NSF.

Is there additional information you wish to provide?
None

PROPOSER DETAILS

Dr Kenichi Matsuoka
Department of Earth and Space Sciences
University of Washington
Box 351310, Seattle, WA
98195
USA

Tel: 206 685 2887
Mobile: no
Fax: 206 543 0489
Email:

Other project members and their affiliation