USAP-DC

0538674
Matsuoka
This award supports a project to evaluate radio-echo intensities in the available SOAR ice-penetrating radar data along grids covering Lake Vostok, and along four regional tracks from Ridge B toward the lake. The project has two objectives; first, it will examine the upper surface of the lake and reflectors hypothesized to be a boundary between the meteoric and accreted ice. They will provide crucial knowledge on the dynamic evolution of the lake. Second, this project will examine a poorly understood echo-free zone within the deep ice in central East Antarctica. This zone may consist of distorted stagnant ice, while its upper boundary may be a shear zone. The SOAR radar data provide a unique resource to examine spatiotemporal water circulation patterns that should be understood in order to select the best direct-sampling strategy to the lake. The Vostok ice core provides a unique opportunity to do this work. First, the path effects, i.e. propagation loss and birefringence, will be derived at the ice-core site using ice temperature, chemistry, and fabric data. Second, lateral variations of the propagation loss will be estimated by tracking chemistry associated with radar-detected isochronous layers, and by inferring temperatures from an ice-flow model that can replicate those layers. Ice-fabric patterns will be inferred from anisotropy in the reflectivity at about 100 radar-track cross-over sites. In terms of broader impacts, a graduate student will be trained to interpret the radar data in the light of radar theory and glaciological context of Lake Vostok and summer workshops for K-12 teachers will be provided in Seattle and New York. This project will contribute to ongoing efforts to study Lake Vostok and will complement the site selection for a North Vostok ice core, which has been proposed by Russia and France as an IPY program.

Person	Role
Matsuoka, Kenichi	Investigator
Winebrenner, Dale	Co-Investigator
Creyts, Timothy	Investigator
Macgregor, Joseph A.	Co-Investigator
Studinger, Michael S.	Co-Investigator
Waddington, Edwin D.	Co-Investigator

Antarctic Glaciology	Award # 0538674
Antarctic Glaciology	Award # 0537752

Vostok_atten
NSIDC-0500_1
creyts_0537752
Vostok_accum
NSIDC-0501_1

None in the Database

Repository	Title (link)	Format(s)	Status
USAP-DC	Millennially Averaged Accumulation Rates for Lake Vostok	None	exist
USAP-DC	Modeled Radar Attenuation Rate Profile at the Vostok 5G Ice Core Site, Antarctica	None	exist

1. MacGregor, J. A., Matsuoka, K., Waddington, E. D., Winebrenner, D. P., & Pattyn, F. (2012). Spatial variation of englacial radar attenuation: Modeling approach and application to the Vostok flowline. Journal of Geophysical Research: Earth Surface, 117(F3), n/a–n/a. (doi:10.1029/2011jf002327)
2. Wolovick, M. J., Bell, R. E., Creyts, T. T., & Frearson, N. (2013). Identification and control of subglacial water networks under Dome A, Antarctica. Journal of Geophysical Research: Earth Surface, 118(1), 140–154. (doi:10.1029/2012jf002555)