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Physical Sciences and Mathematics Commons

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Geology

University of Montana

Geosciences Faculty Publications

Series

2013

Articles 1 - 3 of 3

Full-Text Articles in Physical Sciences and Mathematics

Understanding Greenland Ice Sheet Hydrology Using An Integrated Multi-Scale Approach, A. K. Rennermalm, S. E. Moustafa, J. Mioduszewski, V. W. Chu, R. R. Forster, B. Hagedorn, Joel T. Harper, T. L. Mote, D. A. Robinson, C. A. Shuman, L. C. Smith, M. Tedesco Feb 2013

Understanding Greenland Ice Sheet Hydrology Using An Integrated Multi-Scale Approach, A. K. Rennermalm, S. E. Moustafa, J. Mioduszewski, V. W. Chu, R. R. Forster, B. Hagedorn, Joel T. Harper, T. L. Mote, D. A. Robinson, C. A. Shuman, L. C. Smith, M. Tedesco

Geosciences Faculty Publications

Improved understanding of Greenland ice sheet hydrology is critically important for assessing its impact on current and future ice sheet dynamics and global sea level rise. This has motivated the collection and integration of in situ observations, model development, and remote sensing efforts to quantify meltwater production, as well as its phase changes, transport, and export. Particularly urgent is a better understanding of albedo feedbacks leading to enhanced surface melt, potential positive feedbacks between ice sheet hydrology and dynamics, and meltwater retention in firn. These processes are not isolated, but must be understood as part of a continuum of processes …


Dynamically Downscaled Winter Precipitation Over Complex Terrain Of The Central Rockies Of Western Montana, Usa, Nicholas Loren Silverman, Marco P. Maneta, S.-H. Chen, Joel T. Harper Jan 2013

Dynamically Downscaled Winter Precipitation Over Complex Terrain Of The Central Rockies Of Western Montana, Usa, Nicholas Loren Silverman, Marco P. Maneta, S.-H. Chen, Joel T. Harper

Geosciences Faculty Publications

We evaluate the results of dynamically downscaled winter precipitation over Western Montana using the weather research and forecasting (WRF) model through comparison with estimates from the observationally based parameter-elevation regressions on independent slopes model (PRISM). Seven years (six winters) from 2000 to 2006 are simulated at 4 km resolution to assess the similarities and differences between the two models as well as the implications for hydrologic modeling. Inherent biases in both approaches are apparent, highlighting the difficulty in climate model validation. Results show general agreement between the two models in the spatial distribution of winter precipitation. A principal component analysis …


Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol Jan 2013

Compressional And Em Wave Velocity Anisotropy In A Temperate Glacier Due To Basal Crevasses, And Implications For Water Content Estimation, John Bradford, Joshua Nichols, Joel T. Harper, Toby W. Meierbachtol

Geosciences Faculty Publications

We have conducted a series of experiments designed to investigate elastic and electromagnetic (EM) velocity anisotropy associated with a preferentially aligned fracture system on a temperate valley glacier in south-central Alaska, USA. Measurements include a three-dimensional compressional wave (P-wave) seismic reflection survey conducted over a 300 m x 300 m survey patch, with uniform source grid and static checkerboard receiver pattern. Additionally, we acquired a multiazimuth, multi-offset, polarimetric groundpenetrating radar (GPR) reflection experiment in a wagon-wheel geometry with 94 degrees of azimuthal coverage. Results show azimuthal variation in the P-wave normal-moveout velocity of less than 3% (3765 and 3630 ms …