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Articles 1 - 18 of 18
Full-Text Articles in Physical Sciences and Mathematics
Collaborative Research: Microparticle/Tephra Analysis Of The Wais Divide Ice Core, Karl J. Kreutz, Andrei V. Kurbatov, Mark Wells, Paul Andrew Mayewski
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
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
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
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 …
The Science Behind Climate Change: A Journey To Reedy Glacier, Brenda L. Hall, Molly Schauffler
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 …
Dry Valleys Late Holocene Climate Variability, Karl J. Kreutz, Paul Andrew Mayewski
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: Late Quaternary History Of Reedy Glacier, Brenda Hall
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 …
Satellite Remote Sensing Of Glaciers And Ice Caps In Svalbard, Eurasian High Arctic, Gordon S. Hamilton
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. …
Deglacial Chronology Of The Northern Scott Coast From Relative Sea-Level Curves, Brenda Hall
Deglacial Chronology Of The Northern Scott Coast From Relative Sea-Level Curves, Brenda Hall
University of Maine Office of Research Administration: Grant Reports
This award provides support for three years for a project to develop a radiocarbon chronology for recession of grounded ice from the northwestern Ross Sea Embayment (northern Scott Coast) since the Last Glacial Maximum (LGM). A key unresolved question in Antarctic glaciology concerns the stability of the marine-based West Antarctic ice sheet (WAIS). One way to gain insight into present and future stability is to examine its past behavior. In particular, the timing of deglaciation from the LGM position on the continental shelf is critical for isolating the mechanisms (sea level, climate, ocean temperature, and internal dynamics) that control WAIS …
Ams Radiocarbon Chronology Of Glacier Fluctuations In The South Shetland Islands During The Last Glacial/Interglacial Hemicycle:Implications For Global Climate Change, Brenda L. Hall
University of Maine Office of Research Administration: Grant Reports
This award supports a two year program to produce a new reconstruction of ice extent, elevation and thickness at the Last Glacial Maximum (LGM) for the South Shetland Islands in the Antarctic Peninsula. One field season on Livingston Island will involve mapping the areal extent and geomorphology of glacial drift and determining the elevation and distribution of trimlines. In addition, ice flow direction will be determined by mapping and measuring the elevation of erosional features and the position of erratic boulders. One of the main goals of this work will be to demonstrate whether or not organic material suitable for …
A New Ice Core From The Devon Ice Cap Canadian Arctic: Continued Development Of High-Resolution Proxy Records To Evaluate The Regionalization Of Climate In The Circum-Arctic, George A. Zielinski, Cameron Wake
A New Ice Core From The Devon Ice Cap Canadian Arctic: Continued Development Of High-Resolution Proxy Records To Evaluate The Regionalization Of Climate In The Circum-Arctic, George A. Zielinski, Cameron Wake
University of Maine Office of Research Administration: Grant Reports
The primary goal of this project was to collect an ice core from the Summit of the Devon Ice Cap, Devon Island, Canadian Arctic. A 302-m core was collected during the spring of 1998 with additional field work in 1999. Individuals supported by this grant participated in the field work, although the GSC did the actual drilling. Glacier flow models as well as physical characteristics of the ice and d18O records suggest that basal ice recovered is about 86,000 years old. The first 200 meters were collected under dry drilling conditions, whereas the final 52 meters were collected with a …
Examination Of The 500,000-Year Climate Record In Ice At Mt. Moulton, West Antarctica, Gregory A. Zielinski, Paul Andrew Mayewski
Examination Of The 500,000-Year Climate Record In Ice At Mt. Moulton, West Antarctica, Gregory A. Zielinski, Paul Andrew Mayewski
University of Maine Office of Research Administration: Grant Reports
This project was a pilot project to determine if the ice on Mt. Moulton provides a reliable record of past climatic conditions. The area of study is a several hundred-meter section of blue ice (Trench A) that spans the time period from approximately the early Holocene to over 492k years ago. Dating control is obtained through radiometrically-dated tephra layers (i.e., air fall deposits) within the section (Figure 1) originating from the adjacent Mt. Berlin. Fieldwork during the 1999-2000 field season included the trenching of the complete section with electric chain saws mounted on a wheeled frame. Blocks were extracted and …
A Finite-Element Model Of Basal Water Generated By Melting In An Ice Sheet Model, James L. Fastook
A Finite-Element Model Of Basal Water Generated By Melting In An Ice Sheet Model, James L. Fastook
University of Maine Office of Research Administration: Grant Reports
It is well known that water is produced at the bed of an ice sheet when the temperature of the bed reaches the pressure melting point. The current ice sheet model, with its ability to calculate temperatures throughout the ice sheet, is also able to calculate melt rates at the bed. By incorporating a model of the continuity equation for the basal-water flow, this project will attempt to follow the movement of this water under the ice sheet as it flows from source regions to sink regions. The ability to predict wet-based regions is important to the understanding of the …
Siple Dome Deep Ice Core Glaciochemistry And Regional Survey - A Contribution To The Wais Initiative, Paul Andrew Mayewski, Loren D. Meeker
Siple Dome Deep Ice Core Glaciochemistry And Regional Survey - A Contribution To The Wais Initiative, Paul Andrew Mayewski, Loren D. Meeker
University of Maine Office of Research Administration: Grant Reports
Our project focuses on the analysis and interpretation of major ions and methanesulfonate (in conjunction with the Univ. of Miami) from a deep ice core at Siple Dome, Antarctica. In addition, this study investigates the regional glaciochemical variability on Siple Dome, continuing work begun during the 1994 field season. The first field season for this project was conducted during the 1996/97 austral season. Because this project closely follows work begun in 1994, selected glaciochemical results from 1994 are presented, along with reports that detail Siple Dome research to present.
The Origin Of A Polar Ice Sheet In East Antarctica, George H. Denton
The Origin Of A Polar Ice Sheet In East Antarctica, George H. Denton
University of Maine Office of Research Administration: Grant Reports
This award supports a study to determine the sequence and chronology of events that led to the development of the Antarctic ice sheet. A continental-scale ice sheet probably first developed in East Antarctica close to the Eocene-Oligocene boundary under temperate climatic conditions. The purpose of this project is to determine, from landscape analysis (with a numerical chronology), when (and why) these early temperate conditions gave way to a polar environment in Antarctica. From previous field work and recent photographic analysis, an extensive relict landscape (older than 17 million years) with landforms and erosional features characteristic of temperate glaciation has been …
Powre: High-Resolution Chronology Of Millennial-Scale Lake-Level Fluctuations In The Dry Valleys (Antarctica) From Uranium-Thorium And Radiocarbon Dating, Brenda L. Hall
University of Maine Office of Research Administration: Grant Reports
The Professional Opportunities for Women in Research and Engineering (POWRE) program affords new research and educational enhancement opportunities for women scientists. This project, which addresses the fundamental problem of the cause of millennial-scale climate change, contains components specifically designed to increase the educational and research skills of the principal investigator. She will learn the following new information/skills: 1) thermal ionization mass spectrometry (TIMS) uranium/thorium (U/TH) dating with Dr. G. Henderson at Lamont-Doherty Earth Observatory (LDEO) and Oxford University, 2) millennial-scale climate change with Drs. W. Broecker and G. Bond, LDEO, and with Drs. D. Oppo and L. Keigwin, Woods Hole …
Derived Quantities: A Coupled Dynamic/Thermodynamic Ice Sheet Model, James L. Fastook
Derived Quantities: A Coupled Dynamic/Thermodynamic Ice Sheet Model, James L. Fastook
University of Maine Office of Research Administration: Grant Reports
This award is for support for a program of research involving the use of inverse modeling to derive information from the measured configuration of an ice sheet to yield important information about the conditions both at the bed and within the ice column. It is proposed to convert a column-averaged model to a column- integrated model that accounts explicitly for internal thermodynamics and variations of material properties that depend on this internal temperature field. An existing finite-element 3- D temperature solver will be coupled with an existing finite- element map-plane continuity solver. The result will allow more detailed analysis of …
Deglacial Radiocarbon Chronology Of The Western Ross Sea From Relative Sea-Level Curves, George H. Denton, Brenda Hall
Deglacial Radiocarbon Chronology Of The Western Ross Sea From Relative Sea-Level Curves, George H. Denton, Brenda Hall
University of Maine Office of Research Administration: Grant Reports
This award provides support for one year of funding to perform carbon-14 analyses on samples (seal skin and Adamussium colbecki shells) collected in firm stratigraphic position within numerous raised beaches along the Scott Coast of the western Ross Sea, Antarctica. These measurements will enable the development of a radiocarbon chronology and will result in detailed relative sea- level curves for five separate localities along the Scott Coast. These relative sea-level curves will help to constrain the timing of deglaciation in the western Ross Sea. During the last glaciation, West Antarctic ice expanded into the Ross Sea, merged with East Antarctic …