Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Interaction between permafrost processes and ice-sheet dynamics during deglaciation of the NW Laurentide Ice Sheet  (ICEPIC (ICE sheet and Permafrost Interactions, Canada))

Outline
It is widely accepted that fast flowing ice streams govern the drainage and mass balance of polar ice sheets. In Antarctica, ice-stream motion is controlled largely by basal processes. Thus, ascertaining the interactions between basal ice and the thermal/rheological properties of the glacier bed (e.g. permafrost vs unfrozen conditions) is critical to elucidating the processes that control ice-stream behaviour and, as a result, ice-sheet stability. However, accessing the beds of contemporary ice sheets is logistically difficult and expensive, and the spatial and temporal scales of such observations are fundamentally limited. These problems can be overcome by investigating former ice-sheet beds where permafrost existed before, during and after glacial activity. Such regions are an invaluable archive of information about basal-ice processes and the interaction between ice sheet/streams and their substrate because they preserve buried remnants of basal-ice layers and contain glaciotectonic structures that have not been disturbed by permafrost degradation. ICEPIC comprises 4 inter-disciplinary projects that integrate, for the first time, the fields of permafrost science, glacial geology, glaciology and geochronology in order to carry out a comprehensive study of the interactions between permafrost processes and ice-sheet dynamics during deglaciation of the NW Laurentide Ice Sheet (LIS), Canada. The northwest LIS contained a complex network of palaeo-ice streams that re-organized themselves during retreat. Evidence for their tracks is well preserved on the ground surface and remnants of their basal ice layers are buried in the permafrost stratigraphy. Project 1. Permafrost stratigraphy and environmental change Key question: how does the permafrost stratigraphy vary beneath and either side of the Mackenzie and Anderson palaeo-ice stream tracks? what is the chronology of pre-glacial, glacial and post-glacial events? Methods: (1) Logging, drilling and sampling of ice and sediment stratigraphy;(2) Isotopic, geochemical and petrographic analyses of ground ice;(3) Luminescence dating of aeolian, fluvial and proglacial sediments; (4) Cosmogenic dating of moraines;(5) Numerical modelling of permafrost development and climate change. Project 2. Ice streaming during retreat of the northwest LIS Key question: what role did ice streams play in the punctuated retreat history of the LIS? what are the physical controls on transient ice streaming during deglaciation? Methods: Geomorphological mapping of glacial landforms from satellite imagery and digital stereo air photos, ground checking of landforms and dating of key sites to: (1) Reconstruct ice-flow patterns and drainage basins during sequential margin positions;(2) Map the evolution of warm-based, cold-based areas and “sticky” areas;(3) Produce a detailed retreat map and glacial history of ice streaming. Project 3. Mechanism of ice-stream shutdown Key question: how does permafrost and basal freeze-on affect ice-stream motion? what is the mechanism of palaeo-ice-stream shutdown? Methods:(1) Build a numerical model using digital elevation models and reconstructed ice thicknesses;(2) Simulate basal thermal evolution, including feedbacks on ice flow regime;(3) Elucidate physical controls on palaeoglaciological ice dynamics and derive a retreat history for the LIS;(4) Validate model with observational constraints from geological and geomorphological surveys. Project 4. Glaciotectonic deformation of subglacial and proglacial permafrost. Key question: what were the deformation mechanisms beneath and in front of the ice sheet? what was the sequence of deformation? how do the ice-sediment stratigraphies and glaciotectonic structures relate to their mode of formation? Methods:(1)Logging of stratigraphic sections of glacially-deformed permafrost; (2)Ground penetrating radar survey of stratigraphy and large-scale deformation structures;(3)Identification, measurement and interpretation of glaciotectonic structures.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
The research will improve understanding and quantification of past natural environmental change between two key interrelated parts of the arctic cryosphere (permafrost and ice sheets)(theme 2). Specifically, it will:(1) establish a well-constrained stratigraphic, chronological and palaeoenvironmental framework for permafrost development and glacial history;(2) reconstruct ice-stream activity during Marine Isotope Stage 2;(3) determine the mechanism of ice-stream shutdown, and numerically model ice-stream activity;(4) determine the rheology of sub-marginal and proglacial permafrost. Collectively, these 4 projects will provide important insights into the processes and behaviour of an ice sheet retreating and of permafrost adjusting to climate warming at the end of a Quaternary glacial period. An improved understanding of ice streaming and permafrost associated with the LIS will contribute to a refined knowledge of ice-stream behaviour and predictability in contemporary ice sheets.

What international collaboration is involved in this project?
This project involves polar scientists from Britain (Julian Murton, Mark Bateman, Poul Christoffersen, Chris Clark, Chris Stokes, Richard Waller), Canada (Ian Clark, Olav Lian, Wayne Pollard) and the United States (Slawek Tulaczyk).

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
The field work will be carried out in three adjacent physiographic regions of western Arctic Canada: (1) the Yukon Coastal Plain, (2) the Tuktoyaktuk Coastlands and (3) the Anderson Plain.

Approximate timeframe(s) for proposed field activities:
Arctic: 03/06 – 08/06      03/07 – 08/07      03/08 – 08/08
Antarctic: n/a

Significant facilities will be required for this project:
Required logistical support: (1) twin otter on floats/tundra tyres for fly-camp set outs/downs (from Inuvik; ~30 hours per season); (2) snowmobiles and sleds for spring geophysics; (3) ice-sediment drilling equipment. Support provided by the Polar Continental Shelf Project and the Aurora Research Institute, Inuvik.

Will the project leave a legacy of infrastructure?
No

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

The project would receive logistical support from the Inuvik Research Centre (accommodation, lab. space) and the Polar Continental Shelf Project (tents).

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?


The project is a new autonomous proposal that brings together three groups of experienced scientists who have been studying permafrost and ice-sheet activity independently of each other, in both the northern or southern polar regions.

How will the project be organised and managed?
The project will be organised and managed by a Project Steering Committee consisting of 2 UK scientists (Murton and Stokes) and 2 Canadian Scientists (Pollard and Lian), and chaired by Murton. The Committee will meet annually at the Inuvik Research Centre (Aurora Research Institute), before or after the field season. All project members will be invited to meet from 23–27th June 2008, shortly before the final summer field season, at the 9th International Permafrost Conference at Fairbanks, Alaska, to present initial results and plan for ongoing research after the IPY.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
Produce a poster(s) aimed at the average 16-year-old school pupil and displayed at student open days and presentations at public events such as British Association Festival of Science. Results will be shown on a dedicated project web-site and a resource pack will be prepared for secondary school teachers. Research results will also be communicated to the indigenous peoples of the Canadian Arctic via specially designed information packs.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
Project data (e.g. geophysical, stratigraphical, remote sensing) will be stored in the National Snow and Ice Data Center.

How is it proposed to fund the project?
A number of related grant applications, primarily seeking funding for logistical and analytical costs, will be submitted for NERC for arctic IPY funding. An additional proposal will be submitted to the Leverhulme Trust for funding a post-doctoral researcher to undertake numerical modelling.

Is there additional information you wish to provide?
None

PROPOSER DETAILS

Dr Julian Murton
University of Sussex
Department of Geography
University of Sussex, Brighton
BN1 9QJ
UK

Tel: +44 1273 678293
Mobile: no
Fax: +44 1273 677196
Email:

Other project members and their affiliation