Expressions of Intent for IPY 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Firn Densification Under Surface Melt Conditions: Impacts on Surface Elevation, Runoff, and Englacial Water Delivery, Percolation Facies, Greenland  (Surface Melt of Greenland’s Percolation Zone)

Outline
In situ observations of snow stratigraphy in Greenland’s percolation facies have been limited, primarily because meltwater percolation and refreezing processes compromise the quality of paleoclimatic signals extracted from pits or cores. The percolation facies constitutes a large portion of the ice sheet, however, and is therefore important to Greenland’s hydrology and mass balance. Recent documentation of dramatic thinning of outlet glaciers motivates further investigation of the role of the percolation facies in mass balance and meltwater input processes. Over the last 20 years the area of the west Greenland experiencing surface melt has increased substantially. The impact of melt on hydrologic and stratigraphic processes is unclear. Likely consequences include: 1) densification of accumulating snow due to enhanced ice lens formation from percolating waters; 2) densification from thermo-mechanical compaction of the firn warmed by latent heat; 3) alteration of meltwater runoff/retention processes due to changing firn stratigraphy and thermal structure. We will investigate time/space varying meltwater processes in the percolation facies in the Jakobshavn region of west Greenland. We will conduct a ground traverse in the region of Crawford Point and the EGIG line from about 2025 m to 1500 m elevation to investigate recent changes in near surface stratigraphy. Our traverse route will revisit a ca. 50 km traverse of the EGIG line (T5 to T1) followed by us in 1991. Data collected on our traverse will enable an investigation of over 25 years of stratigraphy forming processes. We will make measurements using snowpits, shallow cores, and ground penetrating radar. Ice layer thickness, depth distribution, and the spatial connectivity of layers will be documented. This project will produce a detailed observationally-based data set that will: 1) document near surface densification rates and rate-of-change of densification; 2) provide ground truth for satellite based measurement of surface melt; 3) improve our understanding of the interaction between infiltration, ice layer formation, and runoff. Each of these has important implications for interpretation of the Jakobshavn region’s surface elevation, mass balance, and flow dynamics.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
This project will quantify the production of meltwater on the Greenland Ice Sheet and determine its flow routing (Theme 1). Time variability of meltwater generation and routing over the last 25 years will be determined (Theme 2). The routing of melt water will be assessed, a topic with global implications for sea level rise (Theme 3). Snow melt processes on the Greenland Ice Sheet, where there is no vegetation, little topography, and relatively little local climate variability, offers a unique laboratory setting to advance our understanding of snow hydrology processes (Theme 4). Finally, this project will involve several graduate students and a PI new to working on polar ice sheet and will thus help train the next generation of polar scientists.

What international collaboration is involved in this project?
This is collaborative work amongst an international team of researchers from USA (Dr. Joel Harper (Univ. of Montana), Dr. Neil Humphrey (Univ. of Wyoming), Dr Tad Pfeffer (Univ. of Colorado)), Norway (Dr. Jack Kohler of the Norwegian Polar Institute) and Denmark (Dr. Karsten Jensen, Aalborg University). q2_1_Location : Field research will be in the percolation facies of the Greenland Ice Sheet. A ground traverse will be conducted as two legs during summer of 2006 and 2007. The traverse will initiate at Crawford Point (2025 m elevation) and will follow the EGIG/PH lines 50 km down glacier to an elevation of 1400 m.

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
Field research will be in the percolation facies of the Greenland Ice Sheet. A ground traverse will be conducted as two legs during summer of 2006 and 2007. The traverse will initiate at Crawford Point (2025 m elevation) and will follow the EGIG/PH line.

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

Significant facilities will be required for this project:
The traverse will be conducted by a field party of five, travelling with skis and sleds. The group will be supported by one small snow machine for towing a gear sled. Air support to and from the ice sheet will be required. Air support and ground equipment (snow machine, camp equipment, instrumentation) could be shared with other parties.

Will the project leave a legacy of infrastructure?
The project will leave behind no permanent instrumentation or structures. The project will produce a record of surface melt processes extending back 25 years from the IPY.

How is it envisaged that the required logistic support will be secured?
Own national polar operator
National agency
Commercial operator
Own 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?
New
New autonomous proposal.

How will the project be organised and managed?
This project will be a collaboration of individual investigators. All investigators have prior and successful experience collaborating on glaciological research. Budget administration will be handled through investigators respective institutions. Analysis of the data collected by the project requires full integration of data types and close collaboration amongst investigators. We have assigned lead responsibilities for each focus effort to insure efficient progress. We stress, however, that there will be significant overlap with sharing of data and work effort.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
Education and outreach will have four facets: 1) Graduate education. Each investigator will direct at least one graduate student working on this project; 2) College courses. Research results will be incorporated into courses taught by each of the investigators; 3) Each investigator is regularly involved with K-12 and public outreach activities.

What are the initial plans of the project to address data management issues (as outlined in the Framework document)?
All field data will be archived with the U.S. National Snow and Ice Data Center.

How is it proposed to fund the project?
U.S. National Science Foundation and/or NASA.

Is there additional information you wish to provide?
None

PROPOSER DETAILS

Dr Joel Harper
Dept. of Geology
32 Campus Drive, #1296
Missoula, Montana
59812
USA

Tel: 406-243-5867
Mobile:
Fax: 406-243-4028
Email:

Other project members and their affiliation

Other Information