Open Access. Powered by Scholars. Published by Universities.®

Physical Sciences and Mathematics Commons

Open Access. Powered by Scholars. Published by Universities.®

Glaciology

Portland State University

Glaciers -- Environmental aspects

Articles 1 - 4 of 4

Full-Text Articles in Physical Sciences and Mathematics

Isotopic Signature Of Massive, Buried Ice In Eastern Taylor Valley, Antarctica: Implications For Its Origin, Christopher B. Gardner, Melisa A. Diaz, Devin F. Smith, Andrew G. Fountain, Joseph S. Levy, W. Berry Lyons Dec 2022

Isotopic Signature Of Massive, Buried Ice In Eastern Taylor Valley, Antarctica: Implications For Its Origin, Christopher B. Gardner, Melisa A. Diaz, Devin F. Smith, Andrew G. Fountain, Joseph S. Levy, W. Berry Lyons

Geography Faculty Publications and Presentations

The coastal regions of the McMurdo Dry Valleys, Antarctica, contain deposits of the Ross Sea Drift, sedimentary material left from the Ross Sea ice sheet from the advance of the West Antarctic ice sheet during the Last Glacial Maximum. Much of this deposit is ice-cored, but data on the stable isotopic composition of water from this ice, which may contain a valuable climate archive, are sparse or incomplete. Widespread thermokarstic ground subsidence in this “coastal thaw zone” of the McMurdo Dry Valleys suggests that these potential records are rapidly being lost due to the melting of ground ice and permafrost. …


The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross Jan 2020

The Seasonal Evolution Of Albedo Across Glaciers And The Surrounding Landscape Of Taylor Valley, Antarctica, Anna Bergstrom, Michael N. Gooseff, Peter T. Doran, Julian M. Cross

Geology Faculty Publications and Presentations

The McMurdo Dry Valleys (MDVs) of Antarctica are a polar desert ecosystem consisting of alpine glaciers, ice-covered lakes, streams, and expanses of vegetation-free rocky soil. Because average summer temperatures are close to 0 Cel., the MDV ecosystem in general, and glacier melt dynamics in particular, are both closely linked to the energy balance. A slight increase in incoming radiation or change in albedo can have large effects on the timing and volume of meltwater. However, the seasonal evolution or spatial variability of albedo in the valleys has yet to fully characterized. In this study, we aim to understand the drivers …


Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors Jan 2019

Reanalysis Of The Us Geological Survey Benchmark Glaciers: Long-Term Insight Into Climate Forcing Of Glacier Mass Balance, Shad O’Neel, Christopher Mcneil, Louis Sass, Caitlyn Florentine, Emily Baker, Andrew G. Fountain, Multiple Additional Authors

Geology Faculty Publications and Presentations

Mountain glaciers integrate climate processes to provide an unmatched signal of regional climate forcing. However, extracting the climate signal via intercomparison of regional glacier mass-balance records can be problematic when methods for extrapolating and calibrating direct glaciological measurements are mixed or inconsistent. To address this problem, we reanalyzed and compared long-term mass-balance records from the US Geological Survey Benchmark Glaciers. These five glaciers span maritime and continental climate regimes of the western United States and Alaska. Each glacier exhibits cumulative mass loss since the mid-20th century, with average rates ranging from −0.58 to −0.30 m w.e. a−1. We produced a …


The ‘Benchmark Glacier’ Concept – Does It Work? Lessons From The North Cascade Range, Usa, Andrew G. Fountain, Matthew J. Hoffman, Frank Granshaw, Jon L. Riedel Jan 2009

The ‘Benchmark Glacier’ Concept – Does It Work? Lessons From The North Cascade Range, Usa, Andrew G. Fountain, Matthew J. Hoffman, Frank Granshaw, Jon L. Riedel

Geology Faculty Publications and Presentations

Benchmark glaciers were established in many alpine areas during the 1960s as part of the International Hydrological Decade to represent ‘typical’ mass and energy processes on glaciers in different climatic regions around the world. These glaciers have received new interest in the past decade because they are used to infer the contribution of alpine glacier wastage to global sea-level rise. We compare South Cascade Glacier, the benchmark glacier for the northwest contiguous USA, and four other secondary glaciers, against the topographic, area and mass changes of 321 glaciers in the surrounding region. Results show that South Cascade Glacier is unusually …