Glaciology Commons^™

Putting The West Antarctic Ice Sheet Into Context, George H. Denton, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a project to develop new insights into the cause and pattern of events during the last glacial termination in South America and Antarctica. One emerging view is that a warming Southern Ocean (SO), driven by a chain of events initiated in the Northern Hemisphere (NH) and tied to the interhemispheric climate seesaw of the last termination, was the underlying mechanism that drove the West Antarctic ice sheet (WAIS) from its Late Glacial Maximum (LGM) position back to present-day grounding lines. This ocean thermal forcing would have impacted WAIS by accelerating basal melt rates on fringing floating ice …

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) …

Collaborative Research: Byrd Glacier Flow Dynamics, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

This award supports a project to understand the flow dynamics of large, fast-moving outlet glaciers that drain the East Antarctic Ice Sheet. The project includes an integrated field, remote sensing and modeling study of Byrd Glacier which is a major pathway for the discharge of mass from the East Antarctic Ice Sheet (EAIS) to the ocean. Recent work has shown that the glacier can undergo short-lived but significant changes in flow speed in response to perturbations in its boundary conditions. Because outlet glacier speeds exert a major control on ice sheet mass balance and modulate the ice sheet contribution to …

Collaborative Research: Glacier-Ocean Coupling In A Large East Greenland Fjord, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

This award will support a study of glacier-fjord interactions in east Greenland. The 'Intellectual Merit' of the proposed study lies in the current understanding that the contribution of the Greenland Ice Sheet to sea level rise more than doubled in the last seven years, mostly because of a widespread and nearly simultaneous acceleration of many glaciers that terminate at tidewater in deep fjords. Understanding the causes of changes in glacier dynamics, and predicting their future trajectories is a topic of enormous scientific and societal importance. The Greenland fjords provide an intimate connection between the ice sheet and the ocean and, …

Collaborative Research: Timing And Structure Of The Last Glacial Maximum And Termination In Southern Peru: Implications For The Role Of The Tropics In Climate Change, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

The role of the tropics in climate change has important implications for understanding both orbital-scale and abrupt climate variations. Yet our ability to assess tropical behavior during major climate events, such as the last glacial maximum (LGM), is limited by poor spatial coverage and insufficient control on sample ages. This project will address this problem by developing well-dated records of glacial fluctuations from the LGM through the termination and late-glacial period at Nevados Coropuna and Allinccapac in southern Peru and use these data in numerical simulations of glacier mass balance and local climate. These sites allow an examination of glacier …

Sensitivity Of The Antarctic Ice Sheet To Climate Change Over The Last Two Glacial/Interglacial Cycles, Brenda Hall, George H. Denton

University of Maine Office of Research Administration: Grant Reports

This project was designed to develop knowledge of the extent of the Ross Sea ice sheet during the last two glaciations and to develop a chronology for the last glacial maximum and penultimate glaciation. To this end, we had the following goals:

1) Map the extent of the Ross Sea ice sheet along the western coast of McMurdo Sound from Taylor Valley to the southern Royal Society Range.
2) Develop a radiocarbon chronology for the last glacial maximum from dates of algal mats within moraines.
3) Produce a uranium-thorium chronology to gain information on the timing of the penultimate glaciation. …

Sensitivity Of The Antarctic Ice Sheet To Climate Change Over The Last Two Glacial/Interglacial Cycles, Brenda L. Hall, George H. Denton

University of Maine Office of Research Administration: Grant Reports

This award supports a project to investigate the sensitivity of the Antarctic ice sheet (AIS) to global climate change over the last two Glacial/Interglacial cycles. The intellectual merit of the project is that despite its importance to Earth's climate system, we currently lack a full understanding of AIS sensitivity to global climate change. This project will reconstruct and precisely date the history of marine-based ice in the Ross Sea sector over the last two glacial/interglacial cycles, which will enable a better understanding of the potential driving mechanisms (i.e., sea-level rise, ice dynamics, ocean temperature variations) for ice fluctuations. This will …

Collaborative Research: St. Elias Erosion And Tectonics Project (Steep), Peter O. Koons, Phaedra Upton

University of Maine Office of Research Administration: Grant Reports

1) Refinement of a regional scale model to include an approximation of the true 3D geometry of the orogen.

2) Develop a new local-scale model that incorporates topography, GPS data, and glacial erosion processes to refine the initial results.

3) Develop a modeling experiment to test the hypothesis that the rise and fall of ice masses during glacial cycles might influence where deformation is focused at any given time.

Colle Gnifetti Ice Core (Kcc) Progress Report (Year One)—Arcadia Ice Core Proposal: Initiatives On The Science Of The Human Past, Paul Mayewski

University of Maine Office of Research Administration: Grant Reports

The Colle Gnifetti glacier of the Monta Rosa Massif on the Swiss-Italian border is perfectly situated to offer insight into the intersection of environment (climate) and culture (history of the economy, political stability, pollution, disease) in medieval Europe. While ice cores previously collected at Colle Gnifetti were sampled at state-of-the-art resolution for the time, it was nevertheless impossible to differentiate annual or finer layering in the period older than 1500 A.D. The 2013 Colle Gnifetti expedition thus sought to collect a new ice core that could be analyzed using the ultra-high-resolution laser based technology developed in the Climate Change Institute’s …

Collaborative Research: Subglacial Water Intrusion In Greenland, Gordon K. Oswald

University of Maine Office of Research Administration: Grant Reports

The project's goals are:

• To analyse radio echo sounding data acquired over the Greenland Ice Sheet by the University of Kansas / CReSIS team with the objective of discriminating between frozen and thawed conditions at the bed of the ice sheet.
• To provide maps of the bed state, with the aim of making them available via the National Snow and Ice Data Centre.
• To support ice sheet modelling activities by providing information on the bed state, thus related to the temperature at the bed and the rheological conditions at the bed.
• To make available to educational establishments information on the …

Collaborative Research: Subglacial Water Intrusion In Greenland, Gordon K. Oswald

University of Maine Office of Research Administration: Grant Reports

A full understanding of the flow and dynamics of an ice sheet will require knowledge of the state of its subglacial interface. While the topography of the Greenland Ice Sheet bed has been studied by radio echo sounding, its state in terms of melting and freezing, which itself affects its future evolution, has been inferred from numerical models, rather than from direct evidence.

This project is for analysis of existing radar echo data gathered under the PARCA and CReSIS programs, with the objective of generating direct evidence of the extent of subglacial water in Greenland and providing the glaciological community …

Collaborative Research: Constraints On The Last Ross Ice Sheet From Glacial Deposits In The Southern Transantarctic Mountains, Brenda Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a project to study the former thickness and retreat history of Shackleton and Beardmore Glaciers which flow through the Transantarctic Mountains (TAMs) into the southern Ross Sea. Lateral moraine deposits along the lower reaches of these major outlet glaciers will be mapped and dated and the results will help to date the LGM and constrain the thickness of ice where it left the Transantarctic Mountains and flowed into the Ross Sea. The intellectual merit of the project is that the results will allow scientists to distinguish between models of ice retreat, which have important implications for former …

Collaborative Research: Sensitivity Of Local Glaciers In Central East Greenland To Holocene Climate Change, Brenda Hall

University of Maine Office of Research Administration: Grant Reports

This award will support an investigation of Holocene glacier fluctuations in the Scoresby Sund region of central East Greenland (~70-72¿N, 22-28¿W) along a transect from a coastal maritime setting to the continental conditions adjacent to the Greenland Ice Sheet. The 'Intellectual Merit' of the proposed study lies in the potential to affirm, or otherwise, the widely-held view that the scale of glacier and ice sheet change being observed today in Greenland is not unique in the Holocene. The current recession of glaciers in the Scoresby Sund region is exposing sub-fossil vegetation that grew at times when glaciers were smaller than …

Collaborative Research: High-Resolution Studies Of Glacier Dynamics At Two Major Outlet Glaciers In East Greenland, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

The Principal Investigators request support for an interdisciplinary, high-resolution study involving remote sensing and field investigations at two of Greenland's largest outlet glaciers. The study of the Helheim and Kangerdlugssuaq Glaciers will integrate seismological, glaciological, and geodetic observations to build an understanding of flow dynamics at major outlet glaciers, which represent a critical junction between the atmosphere, cryosphere, and hydrosphere. The project would be the first long-term occupation of an outlet glacier by a GPS receiver network, and would address questions of flow variation on earthquake to interannual time scales. Recent discoveries have made it clear that our understanding of …

Ice Dynamics And Surface Glaciology Along Us Itase Traverse Routes In East Antarctica, Gordon Hamilton

University of Maine Office of Research Administration: Grant Reports

This award supports a series of field measurements that will improve our understanding of the East Antarctic ice sheet. The objectives of this project are to take advantage of the overland traverse logistics framework provided by US ITASE and to collaborate with other US ITASE investigators to calculate rates of ice sheet thickness change (mass balance) on domes, along elevation contours and along flow lines in East Antarctica using precise global positioning system methods. In addition, the variability (both spatial and temporal) in snow accumulation rates will be assessed using shallow ice cores and ground-penetrating radar profiling, and will provide …

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 …

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) …

Collaborative Research: Grounding-Line Retreat In The Southern Ross Sea - Constraints From Scott Glacier, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a project to investigate late Pleistocene and Holocene changes in Scott Glacier, a key outlet glacier that flows directly into the Ross Sea just west of the present-day West Antarctic Ice Sheet (WAIS) grounding line. The overarching goals are to understand changes in WAIS configuration in the Ross Sea sector at and since the last glacial maximum (LGM) and to determine whether Holocene retreat observed in the Ross Embayment has ended or if it is still ongoing. To address these goals, moraine and drift sequences associated with Scott Glacier will be mapped and dated and ice thickness, …

Collaborative Proposal: 2000+ Year Detailed, Calibrated Climate Reconstruction From A South Pole Ice Core Set In An Antarctic - Global Scale Context, Paul Andrew Mayewski Dr., Karl J. Kreutz, Andrei V. Kurbatov

University of Maine Office of Research Administration: Grant Reports

This award supports a project to examine an existing ice core of opportunity from South Pole (SPRESO core) to develop a 2000+ year long climate record. SPRESO ice core will be an annually dated, sub-annually-resolved reconstruction of past climate (atmospheric circulation, temperature, precipitation rate, and atmospheric chemistry) utilizing continuous, co-registered measurements (n=45) of: major ions, trace elements, and stable isotope series, plus selected sections for microparticle size and composition. The intellectual merit of this project relates to the fact that few 2000+ year records of this quality exist in Antarctica despite increasing scientific interest in this critical time period as …

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 …

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 …

Itase Synthesis Workshop, Paul Mayewski

University of Maine Office of Research Administration: Grant Reports

This award supports a workshop to bring together scientists involved in the International Trans-Antarctic Scientific Expedition (ITASE). Since 1999 the US has supported a program of traverses across both East and West Antarctica (US ITASE). US ITASE is part of the ITASE multi-national effort to understand the past 200-1000+ years of climate change over Antarctica and the Southern Ocean. ITASE is organized under the auspices of Scientific Committee for Antarctic Research (SCAR) and now comprises twenty-one countries. The international representatives from ITASE have met several times in the past to discuss national traverse plans; coordinate efforts; synthesize results; and develop …

Dry Valleys Late Holocene Climate Variability, Karl J. Kreutz, Paul Andrew Mayewski

University of Maine Office of Research Administration: Grant Reports

This award supports a project to collect and develop high-resolution ice core records from the Dry Valleys region of Antarctica, and provide interpretations of interannual to decadal-scale climate variability during the last 2000 years (late Holocene). The project will test hypotheses related to ocean/atmosphere teleconnections (e.g., El Nino Southern Oscillation, Antarctic Oscillation) that may be responsible for major late Holocene climate events such as the Little Ice Age in the Southern Hemisphere. Conceptual and quantitative models of these processes in the Dry Valleys during the late Holocene are critical for understanding recent climate changes, and represent the main scientific merit …

Collaborative Research: West Antarctic Ice Sheet Stability: The Glacial Geologic Record From The Ohio Range Of The Horlick Mountains In The Bottleneck, Harold W. Borns Jr.

University of Maine Office of Research Administration: Grant Reports

This award supports a project to document former high stands and assess the stability of the West Antarctic ice sheet (WAIS) at the Ohio Range near the head of Mercer Ice Stream (formerly Ice Stream A). The field location is situated in the "Bottleneck", a unique, relatively narrow passage in the Transantarctic Mountains connecting the West and East Antarctic ice sheets. The location lies near the ice divide and is thus well situated to determine past interior ice elevation. The research will involve geologic mapping of glacial deposits and erosion features combined with cosmogenic surface exposure dating on the Ohio …

Sger: Is Bolling Warming Recorded By The Southeastern Margin Of The Laurentide Ice Sheet?, Harold W. Borns Jr., Brenda Hall

University of Maine Office of Research Administration: Grant Reports

This award, under the auspices of the Small Grants for Exploratory Research (SGER) program, uses funds to increase the chronologic control for the southeastern margin of the Laurentide Ice Sheet (LIS). Ultimately, the researchers want to explore whether they are able to document the response of the ice sheet to major shifts in atmospheric temperature and assess the ability of the ice sheet to produce large volumes of meltwater.

The effect of prominent climate events, such as the Bolling warming (13,000 radiocarbon years before present), on the dynamics of the Laurentide Ice Sheet (LIS) remains unknown and yet has important …

Collaborative Research: Late Quaternary History Of Reedy Glacier, Brenda Hall

University of Maine Office of Research Administration: Grant Reports

The stability of the marine West Antarctic Ice Sheet (WAIS) remains an important, unresolved problem for predicting future sea level change. Recent studies indicate that the mass balance of the ice sheet today may be negative or positive. The apparent differences may stem in part from short-term fluctuations in flow. By comparison, geologic observations provide evidence of behavior over much longer time scales. Recent work involving glacial-geologic mapping, dating and ice-penetrating radar surveys suggests that deglaciation of both the Ross Sea Embayment and coastal Marie Byrd Land continued into the late Holocene, and leaves open the possibility of ongoing deglaciation …

Collaborative Research: Chronology Of Ice Fluctuations In The South Shetland Islands Since The Last Glacial Maximum, Brenda L. Hall

University of Maine Office of Research Administration: Grant Reports

This award supports a study of the timing of climate changes in the Southern Hemisphere with the goal of reconstructing former ice extent and fluctuations, as well as paleoclimate, along the key latitudinal transect from temperate Tierra del Fuego to the polar Antarctic Peninsula. Samples already in hand will allow the dating of ice fluctuations in the South Shetland Islands (SSI), a critical location where that transect crosses the Antarctic Convergence. Surprisingly little concrete evidence exists concerning former ice extent in the island chain. The results of this study will answer a number of basic questions regarding ice extent and …

Satellite Remote Sensing Of Glaciers And Ice Caps In Svalbard, Eurasian High Arctic, Gordon S. Hamilton

University of Maine Office of Research Administration: Grant Reports

Recent compilations of climate-related observations show that important changes are now underway in the High Arctic, probably as a response to anthropogenic greenhouse gas emissions over the last approximately 250 years. These changes include warming of the troposphere, reductions in sea ice cover, decreases in snow cover area, warming of tundra permafrost, and negative mass balances of glaciers and ice caps. In many instances, observations of change are relatively short in duration or sparse in spatial extent. The Principal Investigators will study glacier and ice cap variations over the approximately last 80 years and at a large scale on Svalbard. …