Glaciology Commons^™

Boron In Antarctic Granulite-Facies Rocks: Under What Conditions Is Boron Retained In The Middle Crust?, Edward S. Grew

University of Maine Office of Research Administration: Grant Reports

This award, provided by the Antarctic Geology and Geophysics Program of the Office of Polar Programs, supports a project to investigate the role and fate of Boron in high-grade metamorphic rocks of the Larsemann Hills region of Antarctica. Trace elements provide valuable information on the changes sedimentary rocks undergo as temperature and pressure increase during burial. One such element, boron, is particularly sensitive to increasing temperature because of its affinity for aqueous fluids, which are lost as rocks are buried. Boron contents of unmetamorphosed pelitic sediments range from 20 to over 200 parts per million, but rarely exceed 5 parts …

The Science Behind Climate Change: A Journey To Reedy Glacier, Brenda L. Hall, Molly Schauffler

University of Maine Office of Research Administration: Grant Reports

This Communicating Research to Public Audiences project focuses on the Reedy Glacier Antarctic research of Brenda Hall (OPP 0229034) and its relevance to the residents of and visitors to Maine. Collaborators include the University of Maine, the Maine Discovery Museum, the Acadia National Park and Cadillac Mountain Sports (an environmentally active retail company with several stores around the state). The primary deliverable is the development of an interactive software program that presents information and experiences in a two-tiered concept approach -- on the Reedy Glacier and its connection to Maine and on the process of science. The software is being …

Us Itase Glaciochemistry Phase 2: East Antarctica, Paul Mayewski

University of Maine Office of Research Administration: Grant Reports

This award supports a project to undertake glaciochemical investigations of the Ross Sea Embayment Drainage System, and portions of Wilkes Land for purposes of understanding annual to multi-centennial scale climate variability. The glaciochemical data that will be collected will contribute to the U.S. component of the International Trans-Antarctic Scientific Expedition and will occur over a period of two years on an overland traverse that will begin at Taylor Dome in Northern Victoria Land and travel to the South Pole. This data, along with similar information collected on a series of earlier traverse in West Antarctica, will contribute to providing an …

Geogram 2009, David J. Keeling Editor, Wku Department Of Geography And Geology

Earth, Environmental, and Atmospheric Sciences Publications

No abstract provided.

Atmospheric Soluble Dust Records From A Tibetan Ice Core: Possible Climate Proxies And Teleconnection With The Pacific Decadal Oscillation, B. Grigholm, Paul A. Mayewski, Kang Shichang, Y. Zang, S. Kaspari, Sharon B. Sneed, Q. Zhang

Climate Change Institute Faculty Scholarship

In autumn 2005, a joint expedition between the University of Maine and the Institute of Tibetan Plateau Research recovered three ice cores from Guoqu Glacier (33°34′37.8″N, 91°10′35.3″E, 5720 m above sea level) on the northern side of Mt. Geladaindong, central Tibetan Plateau. Isotopes (δ¹⁸O), major soluble ions (Na⁺, K⁺, Mg²⁺, Ca²⁺, Cl⁻, NO₃⁻, SO₄²⁻), and radionuclide (β-activity) measurements from one of the cores revealed a 70-year record (1935–2005). Statistical analysis of major ion time series suggests that atmospheric soluble …

Understanding Paleoclimate And Human Evolution Through The Hominin Sites And Paleolakes Drilling Project, Andrew Cohen, Ramon Arrowsmith, Anna K. Behrensmeyer, Christopher Campisano, Craig Feibel, Shimeles Fisseha, Roy Johnson, Zelalem Bedaso, Charles Lockwood, Emma Mbua, Daniel Olago, Richard Potts, Kaye Reed, Robin Renaut, Jean-Jacques Tiercelin, Mohammed Umer

Geology Faculty Publications

Understanding the evolution of humans and our close relatives is one of the enduring scientific issues of modern times. Since the time of Charles Darwin, scientists have speculated on how and when we evolved and what conditions drove this evolutionary story. The detective work required to address these questions is necessarily interdisciplinary, involving research in anthropology, archaeology, human genetics and genomics, and the earth sciences. In addition to the difficult tasks of finding, describing, and interpreting hominin fossils (the taxonomic tribe which includes Homo sapiens and our close fossil relatives from the last 6 Ma), much of modern geological research …

Continuous Profiles Of Electromagnetic Wave Velocity And Water Content In Glaciers: An Example From Bench Glacier, Alaska, Usa, John H. Bradford, Joshua Nichols, T. Dylan Mikesell, Joel T. Harper

Geosciences Faculty Publications

We conducted two-dimensional continuous multi-offset georadar surveys on Bench Glacier, south-central Alaska, USA, to measure the distribution of englacial water. We acquired data with a multi channel 25 MHz radar system using transmitter-receiver offsets ranging from 5 to 150 m. We towed the radar system at 5-10 kmh^-1 with a snow machine with transmitter/receiver positions established by geodetic-grade kinematic deferentially corrected GPS (nominal 0.5 m trace spacing). For radar velocity analyses, we employed reflection tomography in the pre-stack depth-migrated domain to attain an estimated 2% velocity uncertainty when averaged over three to five wavelengths. We estimated water content from …

Seismic Observations Of Transient Subglacial Water-Flow Beneath Macayeal Ice Stream, West Antarctica, J. Paul Winberry, Sridhar Anandakrishnan, Richard B. Alley

All Faculty Scholarship for the College of the Sciences

New seismic observations of harmonic tremors beneath MacAyeal Ice Stream, West Antarctica are reported. Each of the two tremor events that we recorded during a six week period had sustained arrival of 3 Hz energy for approximately 10 minutes. During that time the source location migrated a few kilometers. The harmonic nature of the tremors is interpreted as the result of resonance in subglacial water-filled cracks and conduits. The duration, monochromatic nature, and movement of the tremor indicate that the source mechanism is likely flow in the subglacial water system resulting from the discharge from a small subglacial lake. Our …

Embedded Ice Sheet Model, James L. Fastook

University of Maine Office of Research Administration: Grant Reports

This award supports the development of an embedded ice sheet model, one where a section of the ice sheet (at a mesoscale) is modeled at higher resolution, but is driven by output from a lower-resolution model of the entire ice sheet (at a global scale). In addition to giving higher resolution results, it will be better able to capture the behavior of small-scale, but dynamically important, systems such as ice streams. It will also be possible with the new embedded model to include more complete physics (such as longitudinal stresses). This project will enable the continued development and application of …

Stable Isotopes And Climate Change, Ray Bradley, Rob Snyder

IPY STEM Polar Connections

The following description of the role of the study of stable isotopes in water and carbon dioxide molecules when constructing a record of Earth’s pattern of climate change is an excerpt from:

Climate Change and Society by Raymond S. Bradley & Norman E. Law (2001) Nelson Thornes, Cheltenham, UK (ISBN: 0 7487 5823 2)

Atmospheric Soluble Dust Records From A Tibetan Ice Core: Possible Climate Proxies And Teleconnection With The Pacific Decadal Oscillation, B. Grigholm, P. A. Mayewski, S. Kang, Y. Zhang, Susan Kaspari, S. B. Sneed, Q. Zhang

Geological Sciences Faculty Scholarship

In autumn 2005, a joint expedition between the University of Maine and the Institute of Tibetan Plateau Research recovered three ice cores from Guoqu Glacier (33°34′37.8″N, 91°10′35.3″E, 5720 m above sea level) on the northern side of Mt. Geladaindong, central Tibetan Plateau. Isotopes (δ¹⁸O), major soluble ions (Na⁺, K⁺, Mg²⁺, Ca²⁺, Cl⁻, NO₃⁻, SO₄²⁻), and radionuclide (β‐activity) measurements from one of the cores revealed a 70‐year record (1935–2005). Statistical analysis of major ion time series suggests that atmospheric soluble …

Records Of Volcanic Events Since Ad 1800 In The East Rongbuk Ice Core From Mt. Qomolangma, Jian Zhong Xu, S. Kaspari, Shu Gui Hou, Shi Chang Kang, Da He Qin, Jia Wen Ren, Paul Andrew Mayewski

Earth Science Faculty Scholarship

Continuous Bi profile of the East Rongbuk (ER) ice core near Mt. Qomolangma reveals nine major volcanic events since AD 1800. Compared with Volcanic Explosivity Index (VEI), it shows that the concentrations of Bi in the ER ice core can reflect the major volcanic events within the key areas. This provides a good horizon layer for ice core dating, as well as a basis for reconstructing a long sequence of volcanic records from the Qinghai-Xizang (Tibet) Plateau ice cores.

State Of The Antarctic And Southern Ocean Climate System, Paul Andrew Mayewski, M. P. Meredith, C. P. Summerhayes, J. Turner, A. Worby, P. J. Barrett, G. Casassa, Nancy Bertler, T. Bracegirdle, A. C. Naveira Garabato, D. Bromwich, H. Campbell, Gordon S. Hamilton, W. B. Lyons, Kirk A. Maasch, S. Aoki, C. Xiao, Tas Van Ommen

Earth Science Faculty Scholarship

This paper reviews developments in our understanding of the state of the Antarctic and Southern Ocean climate and its relation to the global climate system over the last few millennia. Climate over this and earlier periods has not been stable, as evidenced by the occurrence of abrupt changes in atmospheric circulation and temperature recorded in Antarctic ice core proxies for past climate. Two of the most prominent abrupt climate change events are characterized by intensification of the circumpolar westerlies (also known as the Southern Annular Mode) between ∼6000 and 5000 years ago and since 1200–1000 years ago. Following the last …

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 …

Characterization Of Firn Microstructure Using Scanning Electron Microscopy: Implications For Physical Properties Measurements And Climate Reconstructions, Nicole Spaulding

Electronic Theses and Dissertations

Samples from 12 East Antarctic firn and ice cores were analyzed using scanning electron micrcoscopy (SEM) in order to first develop a technique for the accurate characterization of physical properties and then to investigate the relationship between the physical microstructure and chemical properties. Both physical properties, such as grain size and porosity, and chemical properties, such as major ion and trace element concentration, provide information about atmospheric temperature changes, impurity content, accumulation rate and deformation history; therefore the characterization of both types of properties is necessary. Further, knowledge of the relationship between the physical and chemical properties may increase our …

The Nature Of Boulder-Rich Deposits In The Upper Big Flat Brook Drainage, Sussex County, New Jersey, Gregory A. Pope, Andrew J. Temples, Sean I. Mclearie, Joanne C. Kornoelje, Thomas J. Glynn

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

The upper reaches of the Big Flat Brook drainage, northwest of Kittatinny Mountain, contain a variety of glacial, pro-glacial, and periglacial deposits from the Late Quaternary. The area is dominated by recessional moraines and ubiquitous ground moraine, along with meltwater deposits, drumlins, and possible postglacial periglacial features. We have identified a curious boulder-rich deposit in the vicinity of Lake Ocquittunk and Lake Wapalanne on upper Big Flat Brook. The area where these boulder deposits occur is mapped (1:24,000 surficial geology) as till. As mapped and observed, larger cobbles and boulders within the till are quartz-pebble conglomerate, quartzite, sandstone, and shale. …

Melting Of Major Glaciers In The Western Himalayas: Evidence Of Climatic Changes From Long Term Msu Derived Tropospheric Temperature Trend (1979-2008), Anup K. Prasad, Keun-Hang Susan Yang, Hesham El-Askary, Menas Kafatos

Mathematics, Physics, and Computer Science Faculty Articles and Research

Global warming or the increase of the surface and atmospheric temperatures of the Earth, is increasingly discernible in the polar, sub-polar and major land glacial areas. The Himalayan and Tibetan Plateau Glaciers, which are the largest glaciers outside of the Polar regions, are showing a large-scale decrease of snow cover and an extensive glacial retreat. These glaciers such as Siachen and Gangotri are a major water resource for Asia as they feed major rivers such as the Indus, Ganga and Brahmaputra. Due to scarcity of ground measuring stations, the long-term observations of atmospheric temperatures acquired from the Microwave Sounding Unit …