Geogram 2011,
2011
Western Kentucky University
Geogram 2011, David J. Keeling Editor, Wku Department Of Geography And Geology
Earth, Environmental, and Atmospheric Sciences Publications
No abstract provided.
Above The Mukpa: The Shifting Ground Of Khumbu's Sacred Geography,
2011
SIT Study Abroad
Above The Mukpa: The Shifting Ground Of Khumbu's Sacred Geography, Noah Brautigam
Independent Study Project (ISP) Collection
The Himalayan region is suffering from global warming,2 and the effects are felt at all scales, from the local to the global. Himalayan glaciers feed ten major Asian rivers, and 1.3 billion people in southern and southeast Asia reside in those river basins (Eriksson, et al. 2009:1). Global warming is melting these glaciers at a rapid rate, with retreat ranging from 10 to 60 meters per year on average, and many smaller glaciers already disappearing (Mool, Bajracharya and Shrestha 2008:1). This research is a study of local perceptions of global warming and glacial melt among the Sherpas of Khumbu, Nepal. …
Collaborative Research: Microparticle/Tephra Analysis Of The Wais Divide Ice Core,
2011
Principal Investigator; University of Maine, Orono
Collaborative Research: Microparticle/Tephra Analysis Of The Wais Divide Ice Core, Karl J. Kreutz, Andrei V. Kurbatov, Mark Wells, Paul Andrew Mayewski
University of Maine Office of Research Administration: Grant Reports
This award supports a project to perform continuous microparticle concentration and size distribution measurements (using coulter counter and state-of-the-art laser detector methods), analysis of biologically relevant trace elements associated with microparticles (Fe, Zn, Co, Cd, Cu), and tephra measurements on the WAIS Divide ice core. This initial three-year project includes analysis of ice core spanning the instrumental (~1850-present) to mid- Holocene (~5000 years BP) period, with sample resolution ranging from subannual to decadal. The intellectual merit of the project is that it will help in establishing the relationships among climate, atmospheric aerosols from terrestrial and volcanic sources, ocean biogeochemistry, and …
Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range,
2011
University of Maine
Melt Regimes, Stratigraphy, Flow Dynamics And Glaciochemistry Of Three Glaciers In The Alaska Range, Seth Campbell, Karl Kreutz, Erich Osterberg, Steven Arcone
Dartmouth Scholarship
We used ground-penetrating radar (GPR), GPS and glaciochemistry to evaluate melt regimes and ice depths, important variables for mass-balance and ice-volume studies, of Upper Yentna Glacier, Upper Kahiltna Glacier and the Mount Hunter ice divide, Alaska. We show the wet, percolation and dry snow zones located below 2700ma.s.l., at 2700 to 3900ma.s.l. and above 3900ma.s.l., respectively. We successfully imaged glacier ice depths upwards of 480m using 40–100MHz GPR frequencies. This depth is nearly double previous depth measurements reached using mid-frequency GPR systems on temperate glaciers. Few Holocene-length climate records are available in Alaska, hence we also assess stratigraphy and flow …
Using Borehole Logging And Electron Backscatter Diffraction To Orient An Ice Core From Upper Fremont Glacier, Wyoming, Usa,
2011
Dartmouth College
Using Borehole Logging And Electron Backscatter Diffraction To Orient An Ice Core From Upper Fremont Glacier, Wyoming, Usa, R. W. Obbard, T. Cassano, K. Aho, G. Troderman, I. Baker
Dartmouth Scholarship
While glacier fabric reflects the accumulated strain, detailed azimuthal information is required to link the microstructure to the flow, and this is not easily gathered at depth. Borehole logging provides a way to obtain a log of azimuthal orientation of tilted stratigraphic features that can be used to orient the core with respect to glacier flow. We demonstrate this using acoustic borehole logs and the ice core from a 162 m borehole in Upper Fremont Glacier, Wind River Range, Wyoming, USA. We measured the dip of tilted dust and bubble layers in the actual ice core, identified them on the …
Ice-Movement History And Kimberlite Indicator Mineral Dispersal Study, Pelly Bay, Lower Boothia Peninsula, And Wager Plateau Areas, Nunavut, Canada,
2011
The University of Western Ontario
Ice-Movement History And Kimberlite Indicator Mineral Dispersal Study, Pelly Bay, Lower Boothia Peninsula, And Wager Plateau Areas, Nunavut, Canada, Carl Ozyer
Electronic Thesis and Dissertation Repository
This study reconstructs the ice flow history of the eastern portion of the Keewatin sector of the Laurentide Ice Sheet by integrating field work, remote imagery, and work by others. The study reveals at least seven ice flow phases during the Wisconsinan, including ice streams. A model was developed using inverse distance weighed (IDW) interpolation with GIS to identify and isolate potential kimberlite bedrock sources in kimberlite indicator mineral-rich areas in the Pelly Bay area, Nunavut. Kimberlite indicator mineral (KIM) data were normalized by “peer size” to better understand how KIM grains from three kimberlite sources are distributed within three …
Does The Normal Stress Parallel To The Sliding Plane Affect The Friction Of Ice Upon Ice?,
2011
Dartmouth College
Does The Normal Stress Parallel To The Sliding Plane Affect The Friction Of Ice Upon Ice?, Andrew L. Fortt, Erland M. Schulson
Dartmouth Scholarship
Sliding experiments were performed at –10 degrees C on smooth surfaces of freshwater columnar-grained S2 ice sliding against itself at a velocity of 8X10 –4 ms –1, with the purpose of examining whether normal stress parallel to the sliding plane affects frictional resistance. This component of the stress tensor was varied (0.20–1.83 MPa) using a loading system operated under biaxial compression, by orienting the sliding plane at two different angles, 26 degrees and 64 degrees, with respect to the principal loading direction. Under these conditions, no evidence was found to indicate that the normal stress in the direction of …
Quantifying 20th Century Glacier Change In The Sierra Nevada, California,
2011
Portland State University
Quantifying 20th Century Glacier Change In The Sierra Nevada, California, Andrew G. Fountain, Hassan J. Basagic
Geology Faculty Publications and Presentations
Numerous small alpine glaciers occupy the high elevation regions of the central and southern Sierra Nevada, California. An inventory based on 1:24,000 topographic maps revealed 1719 glaciers and perennial snowfields for a total area of 39.15 +/- 0.13 km(2). The number of 'true' glaciers, versus non-moving ice, is estimated to be 122 covering 14.89 +/- 0.08 km(2) or 38% of the ice-covered area. Historic photographs, geologic evidence, and field mapping were used to determine the magnitude of area change over the past century at 14 glaciers. The area change between 1903 and 2004 ranged from -31% to -78%, averaging -55%. …
An Ice-Core Proxy For Northerly Air Mass Incursions Into West Antarctica,
2011
University of Maine
An Ice-Core Proxy For Northerly Air Mass Incursions Into West Antarctica, Daniel D. Dixon, Paul Andrew Mayewski, Ian D. Goodwin, Gareth J. Marshall, Rhaelene Freeman, Kirk A. Maasch, Sharon B. Sneed
Earth Science Faculty Scholarship
A 200-year proxy for northerly air mass incursions (NAMI) into central and western West Antarctica is developed from the examination of 19 shallow (21–150 m deep) Antarctic ice-core non-sea-salt (nss) Ca2+ concentration records. The NAMI proxy reveals a significant rise in recent decades. This rise is unprecedented for at least the past 200 years and is coincident with anthropogenically driven changes in other large-scale Southern Hemisphere (SH) environmental phenomena such as greenhouse gas (GHG) induced warming, ozone depletion, and the associated intensification of the SH westerlies. The Hysplit trajectory model is used to examine air mass transport pathways into West …
Roosevelt Island Climate Evolution Project (Rice): Us Deep Ice Core Glaciochemistry Contribution (2011- 2014),
2011
Principal Investigator; University of Maine, Orono
Roosevelt Island Climate Evolution Project (Rice): Us Deep Ice Core Glaciochemistry Contribution (2011- 2014), Paul Andrew Mayewski, Karl J. Kreutz, Andrei V. Kurbatov
University of Maine Office of Research Administration: Grant Reports
This award supports a project to analyze a deep ice core which will be drilled by a New Zealand research team at Roosevelt Island. The objectives are to process the ice core at very high resolution to (a) better understand phasing sequences in Arctic/Antarctic abrupt climate change, even at the level of individual storm events; (b) determine the impact of changes in the Westerlies and the Amundsen Sea Low on past/present/future climate change; (c) determine how sea ice extent has varied in the area; (d) compare the response of West Antarctica climate to other regions during glacial/interglacial cycles; and (e) …
Glacimarine Sedimentation Processes At Kronebreen And Kongsvegen, Svalbard,
2011
Dartmouth College
Glacimarine Sedimentation Processes At Kronebreen And Kongsvegen, Svalbard, Laura M. Kehrl, Robert L. Hawley, Ross D. Powell, Julie Brigham-Grette
Dartmouth Scholarship
Tidewater glaciers deposit sediment at their terminus, thereby reducing the relative water depth. Reduced water depth can lead to increased glacier stability through decreased rates of iceberg calving, glacier thinning and submarine melting. Here we investigate sedimentation processes at the termini of Kronebreen and Kongsvegen, Svalbard. We mapped the fjord floor bathymetry in August 2009 and calculate sedimentation rates based on our bathymetry and that from a similar study in 2005. A grounding-line fan is developing near the current position of the subglacial stream. An older, abandoned grounding-line fan that likely formed between ~1987 and 2001 is degrading near the …
An Emerging Technique: Multi-Ice-Core Multi-Parameter Correlations With Antarctic Sea-Ice Extent,
2011
University of Maine
An Emerging Technique: Multi-Ice-Core Multi-Parameter Correlations With Antarctic Sea-Ice Extent, Sharon B. Sneed, Paul Andrew Mayewski, Daniel A. Dixon
Earth Science Faculty Scholarship
ABSTRACT. Using results stemming from the International Trans-Antarctic Scientific Expedition (ITASE) ice-core array plus data from ice cores from the South Pole and Siple Dome we investigate the use of sodium (Na+), non-sea-salt sulfate (nssSO4 2–) and methylsulfonate (MS–) as proxies for Antarctic sea-ice extent (SIE). Maximum and mean annual chemistry concentrations for these three species correlate significantly with maximum, mean and minimum annual SIE, offering more information and clarification than single ice-core and single species approaches. Significant correlations greater than 90% exist between Na+ and maximum SIE; nssSO4 2– with minimum and mean SIE; and MS– with mean SIE. …
Recent Increase In Black Carbon Concentrations From A Mt. Everest Ice Core Spanning 1860–2000 Ad,
2011
The University of Maine
Recent Increase In Black Carbon Concentrations From A Mt. Everest Ice Core Spanning 1860–2000 Ad, S. D. Kaspari, M. Schwikowski, M. Gysel, M. G. Flanner, Kang Shichang, S. Hou, Paul A. Mayewski
Climate Change Institute Faculty Scholarship
A Mt. Everest ice core spanning 1860–2000 AD and analyzed at high resolution for black carbon (BC) using a Single Particle Soot Photometer (SP2) demonstrates strong seasonality, with peak concentrations during the winter-spring, and low concentrations during the summer monsoon season. BC concentrations from 1975–2000 relative to 1860–1975 have increased approximately threefold, indicating that BC from anthropogenic sources is being transported to high elevation regions of the Himalaya. The timing of the increase in BC is consistent with BC emission inventory data from South Asia and the Middle East, however since 1990 the ice core BC record does not indicate …
Final Evaluation Report,
2011
University of Massachusetts Amherst
Final Evaluation Report, Sagefox Consulting Group
IPY STEM Polar Connections
No abstract provided.
Photonic Non-Destructive Measurement Methods For Investigating The Evolution Of Polar Firn And Ice,
2011
The University of Maine
Photonic Non-Destructive Measurement Methods For Investigating The Evolution Of Polar Firn And Ice, Daniel James Breton
Electronic Theses and Dissertations
When snow falls on glaciers or ice sheets, it persists for many tens, hundreds and sometimes thousands of years before becoming ice. The granular material in between fresh snow and glacial ice is known as firn and is generally 50 to 100 m thick over polar ice sheets. The compaction mechanism of firn into ice (called densification) has important glaciological ramifications in determination of ice sheet stability and related sea level rise effects via remote sensing altimetry. Firn densification is also important for correctly interpreting ice core paleoclimate records, especially those analyzing gases trapped in air bubbles within the glacial …
Encyclopedia Of Snow, Ice And Glaciers,
2011
Texas A & M University - College Station
Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya
Geology Faculty Publications
The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …
Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin,
2011
University of Nevada, Reno
Timing, Distribution, Amount, And Style Of Cenozoic Extension In The Northern Great Basin, Christopher D. Henry, Allen J. Mcgrew, Joseph P. Colgan, Arthur W. Snoke, Matthew E. Brueseke
Geology Faculty Publications
This field trip examines contrasting lines of evidence bearing on the timing and structural style of Cenozoic (and perhaps late Mesozoic) extensional deformation in northeastern Nevada. Studies of metamorphic core complexes in this region report extension beginning in the early Cenozoic or even Late Cretaceous, peaking in the Eocene and Oligocene, and being largely over before the onset of “modern” Basin and Range extension in the middle Miocene. In contrast, studies based on low- temperature thermochronology and geologic mapping of Eocene and Miocene volcanic and sedimentary deposits report only minor, localized extension in the Eocene, no extension at all in …
A Scanning Electron Microscope Technique For Identifying The Mineralogy Of Dust In Ice Cores,
2011
Dartmouth College
A Scanning Electron Microscope Technique For Identifying The Mineralogy Of Dust In Ice Cores, Rachel Obbard, Ian Baker, David Prior
Dartmouth Scholarship
Dust particles in an ice core from East Rongbuk Glacier on the northern slope of Qomolangma (Mount Everest; 28deg 01' N, 58deg 00' E; 6518m a.s.l.), central Himalaya, have been identified as mica using a combination of scanning electron microscope-based techniques and energy-dispersive X-ray spectroscopy to identify the elements present, and electron backscatter diffraction to identify the crystal type. This technique for identifying individual crystalline dust particles in samples of glacial ice could be especially useful in the future for identifying water-soluble crystals in ice, for studying the strain history (glaciotectonics) of basal ice or in studies of icemica composites …
Seasonal Ice Mass-Balance Buoys: Adapting Tools To The Changing Arctic,
2011
Dartmouth College
Seasonal Ice Mass-Balance Buoys: Adapting Tools To The Changing Arctic, Chris Polashenski, Don Perovich, Jackie Richter-Menge, Bruce Elder
Dartmouth Scholarship
Monitoring the local mass balance of Arctic sea ice provides opportunities to attribute the observed changes in a particular floe’s mass balance to specific forcing phenomena. A shift from multi- year to seasonal ice in large portions of the Arctic presents a challenge for the existing Lagrangian array of autonomous ice mass-balance buoys, which were designed with a perennial ice cover in mind. This work identifies the anticipated challenges of operation in seasonal ice and presents a new autonomous buoy designed to monitor ice mass balance in the seasonal ice zone. The new design presented incorporates features which allow the …
Arctic Sea-Ice Melt In 2008 And The Role Of Solar Heating,
2011
Dartmouth College
Arctic Sea-Ice Melt In 2008 And The Role Of Solar Heating, Donald K. Perovich, Jacqueline A. Richter-Menge, Kathleen F. Jones, Bonnie Light
Dartmouth Scholarship
There has been a marked decline in the summer extent of Arctic sea ice over the past few decades. Data from autonomous ice mass-balance buoys can enhance our understanding of this decline. These buoys monitor changes in snow deposition and ablation, ice growth, and ice surface and bottom melt. Results from the summer of 2008 showed considerable large-scale spatial variability in the amount of surface and bottom melt. Small amounts of melting were observed north of Greenland, while melting in the southern Beaufort Sea was quite large. Comparison of net solar heat input to the ice and heat required for …
