Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Monitoring of Antarctic sea ice thickness by buoys and remote sensing  (Waves across the Antarctic)

Outline
To complement other work that has been proposed as part of a major IPY effort to map the overall field of Antarctic sea ice thickness, we propose the hemispheric use of two proven wave techniques, viz. (1) the analysis of SAR imagery from around the entire periphery of the Antarctic during the autumn/winter seasons to map the mean thickness of pancake ice in the marginal ice zone by the technique reported by Wadhams, Parmiggiani, De Carolis, Desiderio and Doble (GRL, 2004), which involves analysis of the change in the dispersion relation of ocean waves passing through the ice using spectral analysis of image subscenes; (2) at the same time, deployment deep within the ice cover of a series of 12 Nagurny buoys, tiltmeter buoy systems which have been used successfully in the Arctic in the GreenICE and SITHOS EU projects, and which transmit the spectra of flexural-gravity waves by satellite; the peak of the spectrum is a function of ice thickness. These are two completely separate techniques, using two different types of wave (normal ocean waves with altered dispersion for the ice edge; low amplitude flexural-gravity waves for the deep interior), yet the two methods complement each other and together allow most of the ice cover to be monitored. Neither technique has been used on other than an experimental scale hitherto, and IPY is an opportunity to make use of their full potential for Antarctic sea ice thickness monitoring. The experiment perfectly complements other large-scale Antarctic sea ice projects that are being proposed for IPY. IPAB (the International Programme for Antarctic Buoys) has proposed a one-off deployment of up to 100 satellite-tracked position-only buoys to map the whole field of Antarctic ice thickness; the Nagurny buoys will form an intelligent part of this array. A programme of ice thickness profiling from AUVs has also been proposed by the ASPECT (Antarctic sea ice properties and climate) committee of SCAR for the Antarctic and by the IPY “AV Explorers” bid for both hemispheres; these other measurements span the gap between the outer ice edge region, which can be monitored by SAR, and the far interior, where Nagurny buoys are at their best. The buoys can be deployed by parachute and do not require a landing; the SAR technique simply requires large-scale access to Envisat or Radarsat SAR imagery for a year.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
The project will establish a new baseline parameter for the Antarctic – the overall distribution of sea ice thickness. This will be vital for the determination of changes due to global warming (themes 1 and 2). The overall field of thickness will determine links with ENSO (theme 3), while the diagnostic use of waves for large-scale thickness monitoring is itself a frontier in science (theme 4). In mapping spectra, the sensors will also monitor lower-latitude processes such as tsunamis and microseisms, allowing the Southern Ocean to be a vantage point for global monitoring (theme 5).

What international collaboration is involved in this project?
Collaboration with CNR in Italy on SAR work: Bologna (Parmiggiani) and Bari (De Carolis); collaboration with Russia on tiltmeter buoy analysis (Nagurny, St Petersburg).

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
Circumpolar Antarctic coastal region in early winter for buoy deployments.

Approximate timeframe(s) for proposed field activities:
Arctic: n/a
Antarctic: 04/07 – 06/07      04/08 – 06/08      

Significant facilities will be required for this project:
Access to SAR imagery (already arranged). Use of flight time on Antarctic research/supply aircraft at various longitudes to drop parachute buoys (about 3 nations will cover range of longitudes required, e.g. UK; Japan; Australia; US).

Will the project leave a legacy of infrastructure?
The buoys will last about 2 years. The data will be added to the data archives of ASPECT and of IPAB.

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

Has the project been "endorsed" at a national or international level?
No

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

It is autonomous, but coupled to the proposals which relate to IPAB buoy networks and to AUV deployments (e.g. AV Explorer).

How will the project be organised and managed?
The Italian partners will organise and manage the SAR analysis. The UK partners will organise buoy construction (at SAMS), deployment, data collection and analysis, drawing on advice from Nagurny. Overall data interpretation, archiving and transmission will be organised by a management committee of all partners. Buoy positional data will be immediately made available on GTS and to IPAB archives.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
As thicknesses change during the life of the project, the potential causes (temperature and wind fields) can be displayed alongside in real time and the whole made into a web-based demonstration or interactive project for students.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
In real time buoy data will go on GTS and to IPAB. After post-processing, SAR- and buoy-based thicknesses will be stored in the Antarctic Sea Ice Thickness Project (associated with ASPECT) database and made available to modelling groups.

How is it proposed to fund the project?
Author already has access to SAR imagery. Rest of funding will be by application to NERC (UK), PNRA (Italy), ESA (both).

Is there additional information you wish to provide?
None

PROPOSER DETAILS

Professor Peter Wadhams
Dept. of Applied Maths & Theoretical Physics
University of Cambridge
Wilberforce Road, Cambridge
CB3 0WA
UK

Tel: 44-1223-760370
Mobile: 44-0774-8032371
Fax: 44-1223-760493
Email:

Other project members and their affiliation