Expressions of Intent for International Polar Year 2007-2008 Activities

Expression of Interest Details

PROPOSAL INFORMATION

Black carbon in Arctic snow and ice, and its effect on surface albedo  (Soot in Arctic snow and ice)

Outline
Small light-absorbing carbonaceous particles ("black carbon", or soot) are produced by incomplete combustion in burning of fossil fuels or biomass (e.g. forest fires). The particles are often carried for several days by the atmosphere before being scavenged by raindrops or snow crystals. Our radiative transfer modeling and our previous published measurements indicate that parts-per-billion amounts of soot can reduce snow albedo significantly, potentially affecting the Arctic climate and the stability of sea ice. In our previous work, the soot content of snow on land and sea in the western Arctic was measured in 1984, suggesting possible reductions of albedo of 0-4%. However, there are indications from our 1998 measurements in SHEBA that snow in the Arctic Ocean may now be less polluted than 20 years ago. We propose to update the earlier survey and to make it more comprehensive, covering the eastern Arctic as well. Samples will be taken during March-June ! (i.e., near the time of maximum snow depth) on the Arctic Ocean, in the wet-snow zone of the Greenland Ice Sheet, and in Arctic tundra areas of Canada, Iceland, Scandinavia, Svalbard, Siberia, and Alaska. Glacier ice will be sampled in summer in the ablation zone of the Greenland Ice Sheet; there is evidence that its albedo is reduced by soot as well. Snow samples will be taken at several vertical levels through the snow pack. Spectral albedo will be measured at some locations to relate the soot concentrations to their radiative effects. Snow samples will be collected by project personnel and also by volunteer researchers engaged in other projects at remote field camps. The snow will be melted and filtered; the filters are then analyzed for light transmission at four wavelengths to separate the contributions to absorption by soot and dust. The snow must be kept frozen until immediately before filtering, to avoid losses of soot to the container walls and to avoid algal growth; therefore, much of the analysis will be done near the collection sites.

What significant advance(s) in relation to the IPY themes and targets can be anticipated from this project?
Recent climate modeling (J. Hansen et al., J. Geophys. Res., in press) has identified soot in snow as a large uncertainty in forcing of global climate change. This work will quantify the soot and its effect on the albedo and energy budgets of snow, sea ice, and glacier ice.

What international collaboration is involved in this project?
Collaborators include Carl-Egede Bøggild (a researcher with the Greenland Geological Survey who is studying soot), Vladimir Radionov in Russia (with whom we have collaborated in the past), Tomas Johannesson in Iceland (a former graduate student at University of Washington), and David Barber (Canadian sea-ice researcher).

FIELD ACTIVITY DETAILS

Geographical location(s) for the proposed field activities:
Siberia, Scandinavia, Svalbard, Iceland, Greenland, Arctic Canada, Alaska, Arctic Ocean

Approximate timeframe(s) for proposed field activities:
Arctic: 03/2007-06/2007       03/2008-06/2008      
Antarctic: n/a

Significant facilities will be required for this project:
Transport to sites in Greenland and in the Arctic Ocean will be shared with other projects. The North Pole Environmental Observatory will be used. Existing research stations in Svalbard, Iceland, Sweden, and the Siberian Arctic Islands will be used. An over-snow traverse across Arctic Alaska and Canada will collect samples.

Will the project leave a legacy of infrastructure?
Several kits will be built for collecting, melting, and filtering snow. Improved instrumentation for photometric processing of the samples will be constructed.

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

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

The only prior large-scale evaluation was by Clarke and Noone in 1983-4. In 1998 snow samples were analyzed by Grenfell upwind of the SHEBA ship, and in 2000-2002 in the vicinity of Barrow (Alaska). Grenfell is sampling snow-free granular sea ice during August-September 2005 on a trans-Arctic ship voyage.

How will the project be organised and managed?
Management will be by Grenfell and Warren at the University of Washington and Clarke at the University of Hawaii. Fieldwork (snow collection and radiation measurements) will be conducted by Warren, Grenfell, and their students, and collaborators listed below. Field workers on other Arctic projects will be enlisted to collect snow samples for us, as was organized by Clarke in 1983-4.

What are the initial plans of the project for addressing the education, outreach and communication issues outlined in the Framework document?
The Clean Air Task Force (Boston, USA) is publicizing this project. Our website will be developed for public presentation. Graduate students will be trained as part of this project.

What are the initial plans of the project to address data management issues (as outlined in the Framework document?
Results of our research will be posted on our website before publication

How is it proposed to fund the project?
U.S. National Science Foundation

Is there additional information you wish to provide?
Additional collaborators (beyond the six listed below): Tomas Johannesson (Icelandic Meteorological Office) David Barber (University of Manitoba, Canada)

PROPOSER DETAILS

Professor Stephen Warren
University of Washington
Department of Atmospheric Sciences
Box 351640 Seattle WA
98195
USA

Tel: 206-543-7230
Mobile: no
Fax: 206-543-0308
Email:

Other project members and their affiliation