Glaciology Commons^™

Sensitivity Of The Relationship Between Antarctic Ice Shelves And Iron Supply To Projected Changes In The Atmospheric Forcing, Michael S. Dinniman, Pierre St-Laurent, Kevin R. Arrigo, Eileen E. Hofmann, Gert L. Van Dijken

CCPO Publications

Upward advection or mixing of iron-rich deep waters due to circulation changes driven by the rate of basal ice shelf melt was shown to be a primary control on chlorophyll a production in coastal polynyas over the Antarctic continental shelf. Here, the effects of atmospheric changes projected in 2100 on this relationship were examined with a 5-km resolution ocean/sea ice/ice shelf model of the Southern Ocean with different simulated dissolved iron sources and idealized biological uptake. The atmospheric changes are added as idealized increments to the forcing. Inclusion of a poleward shift and strengthening of the winds, increased precipitation, and …

Datasets From: Application Of Aerial Insar To Measure Glacier Elevations, Bryce Glenn, Andrew G. Fountain, Delywn Moller

Geology Faculty Datasets

In September 2016 NASA flew an interferometric synthetic aperture radar (GLISTIN) over most of the glacier-covered regions of the coterminous USA for the purpose of mapping the surface elevation of the glaciers. Where multiple passes were flown over the same ground track, the data were mosaiced together to improve data coverage and elevation accuracy. These data are to be used with elevations collected by past and future efforts to calculate volume change of glaciers.

The data were the basis for:

Glenn, Bryce Allen, "Assessing Airborne Radar to Map Glacier Elevations in Alpine Terrain Including Estimated Glacier Volume Change …

Data From: The Geography Of Glaciers And Perennial Snowfields In The American West, Andrew G. Fountain, Bryce Glenn, Hassan J. Basagic

Geology Faculty Datasets

A comprehensive mid-20th century inventory of glaciers and perennial snowfields (G&PS) was compiled for the American West, west of the 100° meridian. The inventory was derived from U.S. Geological Survey 1:24,000 topographic maps based on aerial photographs acquired during 35 years,1955–1990.

Dataset: A Numerical Simulation Of The Ocean, Sea Ice And Ice Shelves In The Amundsen Sea (Antarctica) Over The Period 2006-2022 And Its Associated Code And Input Files, Pierre St-Laurent

Data

A three-dimensional numerical model of the Amundsen Sea (Antarctica) was used to simulate the period Jan.2006-Mar.2022 under consistent atmospheric/oceanic forcings, bathymetry/ice shelf topography, and model equations/parameters. The model is an implementation of the Regional Ocean Modeling System (ROMS, https://www.myroms.org/) with extensions for sea ice (Budgell 2005) and ice shelves (Dinniman et al. 2011). It simulates the ocean hydrography and circulation, sea ice thermodynamics and dynamics, and the basal melt of the ice shelves, with a uniform horizontal mesh of 1.5km and 20 topography-following vertical levels. Forcings include the ERA5 reanalysis (3-hourly), 10 tidal constituents from CATS 2008, and ocean/sea ice …

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. …

Investigation Of Cryptotephra In Polar Ice Cores, Meredith Helmick

Electronic Theses and Dissertations

Volcanic ash (tephra) present within polar ice cores greatly supplements our understanding of past volcanism and its impacts on society and the state of the climate system. This thesis investigates the utility and limitations of ice core tephrochronology in answering questions related to volcanic source identification of ice core glaciochemical signals, tephrostratigraphy of an Antarctic ice core, and the timing of major and climate forcing eruptions. This thesis explores the efficacy of SEM-EDS measurements on ultra-fine (µm) volcanic particles for the purpose of geochemically characterizing a non-visible ice-embedded tephra and the subsequent identification of the volcanic source. In combination with …

Geomorphic And Paleoclimatic Implications Of Glacial Extent Records In The Sierra Nevada Del Cocuy, Colombia During Termination 1, Jordan Nickerson Herbert

Dartmouth College Master’s Theses

Reconstructions of past glacial extents using geomorphic mapping and cosmogenic dating provide an opportunity to infer past climates. A record of the past extents of tropical mountain glaciers is particularly useful because there are few other means to reconstruct past temperatures in high-altitude, low-latitude locations. The tropics play an outsized role in mediating global climate, yet there is a lack of understanding of how the tropics may have influenced past climate changes such as the most recent deglaciation (Termination 1, ~18–11.7 ka). Improving reconstructions of tropical mountain glaciers will aid in understanding the role of the tropics in the global …

Detecting Upland Glaciation In Earth’S Pre-Pleistocene Record, Gerilyn S. Soreghan, Lily Pfeifer, Dustin E. Sweet, Nicholas G. Heavens

School of Earth & Environment Faculty Scholarship

Earth has sustained continental glaciation several times in its past. Because continental glaciers ground to low elevations, sedimentary records of ice contact can be preserved from regions that were below base level, or subject to subsidence. In such regions, glaciated pavements, ice-contact deposits such as glacial till with striated clasts, and glaciolacustrine or glaciomarine strata with dropstones reveal clear signs of former glaciation. But assessing upland (mountain) glaciation poses particular challenges because elevated regions typically erode, and thus have extraordinarily poor preservation potential. Here we propose approaches for detecting the former presence of glaciation in the absence or near-absence of …

Glaciochemical Investigations In Three Southern Hemisphere Mountain Sites, Mariusz Potocki

Electronic Theses and Dissertations

The research presented in this dissertation focuses on glaciochemical records of trace elements, major ions, and stable water isotopes from three mountain regions: the Antarctic Peninsula, the Central Chilean Andes, and South Georgia Island.

The first section reports a significant increase in U concentration over 27 years on Detroit Plateau, Antarctic Peninsula. U concentrations in the ice core increase by as much as 102 between the 1980s and 2000s, accompanied by increased variability in recent years. The U concentration increase coincides with expanded open pit mining in the Southern Hemisphere, most notably Australia. Since other land-source dust elements do not …

Evidence For An Early Saginaw Lobe Ice Retreat And Drainage Adjustments Across Southern Michigan, Usa, Nathan Erber

Dissertations

The Saginaw lobe of the Laurentide Ice Sheet (LIS), flowed out of Saginaw Bay, across Lower Michigan and into northern Indiana. As it retreated, the Saginaw lobe deposited the Sturgis moraine, a recessional moraine of the lobe in southern Michigan. Positioned to the west and east of the Saginaw lobe were the Lake Michigan and Huron-Erie lobes, respectively. These lobes retreated across the region asynchronously, with the Saginaw lobe retreating first. The asynchronous behavior of the lobes allowed for the Lake Michigan and Huron-Erie lobes to overprint and alter landscapes once occupied by the Saginaw lobe ice.

The Kalamazoo moraine, …

Antarctic Ice Sheet Stability During Warm Periods: Integrating Numerical Modeling With Geologic Data, Anna Ruth W. Halberstadt

Doctoral Dissertations

Sea level rise is one of the major social and environmental challenges that threatens modern civilization, yet the response of polar ice sheets to future warming is deeply uncertain. Mass loss from the Antarctic Ice Sheet is projected to dominate global sea level rise in the near future, but how much, and when, remains a key unknown. The challenges associated with projecting Antarctica’s future sea level contribution are derived from a knowledge gap of physical ice sheet processes in a world warmer than today, and a lack of understanding of climatic thresholds that drive potentially irreversible retreat.

Future and even …

Analysis Of Fossil Pollen From A Pleistocene Cypress Forest Preserved On The Northern Gulf Of Mexico Continental Shelf, Kathryn Joyce Garretson

Master's Theses

This study presents the findings of fossil pollen analysis performed on terrestrial sediments preserved on the northern Gulf of Mexico continental shelf (site hereafter known as the Underwater Forest or DF). This research aims to establish vegetation composition on a continental shelf glacial refuge and provide a better understanding of vegetation response to sea-level rise. Two cores (15DF1 and 15DF3B) located at different locations within the forest were recovered and analyzed. Pollen results from both cores were similar, with high percentages of Taxodium and Nyssa pollen in the lowermost sections reflecting an assemblage typical of contemporary baldcypress swamps. Pollen assemblages …

Aquatic Diversity In A Changing Tropical Andean Glacierized Catchment: Macroinvertebrates Reveal Possible Important Consequences To The Chimborazo Region As Glaciers Recede And The Climate Continues To Change, Tanner Thomas

Independent Study Project (ISP) Collection

Tropical Andean glaciers are retreating rapidly, and their disappearance will have drastic consequences for the people and ecosystems that depend on them. While they have begun to receive the attention they deserve in scientific literature, much is still not known. Majority of these investigations have taken place on the Volcán Antisana, while other important glacierized systems, like the Volcán Chimborazo have received little attention. This investigation aimed to a) evaluate the possible effects of glacier loss and climate change on aquatic ecosystems by comparing glacial meltwater, non-glacial and mixed streams, and b) to evaluate the effects of pasture intensity on …

Cosmogenic Ages Indicate No Mis 2 Refugia In The Alexander Archipelago, Alaska, Caleb K. Walcott, Jason P. Briner, James F. Baichtal, Alia J. Lesnek, Joseph M. Licciardi

Publications and Research

The late-Pleistocene history of the coastal Cordilleran Ice Sheet remains relatively unstudied compared to chronologies of the Laurentide Ice Sheet. Yet accurate reconstructions of Cordilleran Ice Sheet extent and the timing of ice retreat along the Pacific Coast are essential for paleoclimate modeling, assessing meltwater contribution to the North Pacific, and determining the availability of ice-free land along the coastal Cordilleran Ice Sheet margin for human migration from Beringia into the rest of the Americas. To improve the chronology of Cordilleran Ice Sheet history in the Alexander Archipelago, Alaska, we applied 10Be and 36Cl dating to boulders and glacially sculpted …

Black Carbon And Organic Carbon Dataset Over The Third Pole, Shichang Kang, Yulan Zhang, Pengfei Chen, Junming Guo, Qianggong Zhang, Zhiyuan Cong, Susan Kaspari, Lekhendra Tripathee, Tanguang Gao, Hewen Niu, Xinyue Zhong, Xintong Chen, Zhaofu Hu, Xiaofei Li, Yang Li, Bigyan Neupane, Fangping Yan, Dipesh Rupakheti, Chaman Gul, Wei Zhang, Guangming Wu, Ling Yang, Zhaoqing Wang, Chaoliu Li

Geological Sciences Faculty Scholarship

The Tibetan Plateau and its surroundings, also known as the Third Pole, play an important role in the global and regional climate and hydrological cycle. Carbonaceous aerosols (CAs), including black carbon (BC) and organic carbon (OC), can directly or indirectly absorb and scatter solar radiation and change the energy balance on the Earth. CAs, along with the other atmospheric pollutants (e.g., mercury), can be frequently transported over long distances into the inland Tibetan Plateau. During the last decades, a coordinated monitoring network and research program named “Atmospheric Pollution and Cryospheric Changes” (APCC) has been gradually set up and continuously operated …

Snow Cover Variability And Trend Over The Hindu Kush Himalayan Region Using Modis And Srtm Data, Nirasindhu Desinayak, Anup K. Prasad, Hesham El-Askary, Menas Kafatos, Ghassem R. Asrar

Mathematics, Physics, and Computer Science Faculty Articles and Research

Snow cover changes have a direct bearing on the regional and global energy and water cycles and the change in the Earth's climate conditions. We studied the relatively long-term (2000–2017) altitudinal spatiotemporal changes in the coverage of snow and glaciers in one of the world's largest mountainous regions, the Hindu Kush Himalayan (HKH) region, including Tibet, using remote sensing data (5 km grid resolution) from the Moderate Resolution Imaging Spectroradiometer (MODIS) on board the Terra satellite. This dataset provided a unique opportunity to study zonal and hypsographic changes in the intra-annual (accumulating season and melting season) and interannual variations in …

A Comparative Analysis Of The Andes And The Himalayas: How Climate Change Effects The Health Of Glaciers And The Social Impacts This Has On Surrounding Communities, Jacqueline Mountford

Environmental Studies Honors Papers

The glacial ice in both the Andean and Himalayan Mountain ranges act as water towers for the billions of people that live within their watersheds. Throughout the year, these communities rely on the glacial meltwater to increase the flow of rivers, but this meltwater is the most impactful during the dry season when there is less precipitation. Communities in both the Andes and Himalayas use this glacial meltwater for human and animal consumption, agricultural purposes, and harnessing hydroelectric power as a clean energy source. One of the biggest worries for scientists and people around the world is how climate change …

Late Quaternary Glacier Fluctuations At Picayune Lake, Northern California, Aidan Patrick Cowan

Cal Poly Humboldt theses and projects

The Klamath Mountains are a 233-km-long (north to south) mountain range located in northern California that shows extensive geomorphic evidence of Pleistocene glaciation. Within the Klamath’s there are many highland lakes, which record evidence of glacial deposition, one of which is Picayune Lake. Lake sediment data collected from Picayune Lake offers insights into the glaciation, and broader depositional history of the Picayune Lake Valley, as well as the climate history of the Klamath Mountains region. I measured magnetic susceptibility, loss on ignition, and grain size in sediment cores and used radiocarbon dating to determine a chronology of glacier fluctuations in …

A Non-Deterministic Deep Learning Based Surrogate For Ice Sheet Modeling, Hannah Jordan

Graduate Student Theses, Dissertations, & Professional Papers

Surrogate modeling is a new and expanding field in the world of deep learning, providing a computationally inexpensive way to approximate results from computationally demanding high-fidelity simulations. Ice sheet modeling is one of these computationally expensive models, the model used in this study currently requires between 10 and 20 minutes to complete one simulation. While this process is adequate for certain applications, the ability to use sampling approaches to perform statistical inference becomes infeasible. This issue can be overcome by using a surrogate model to approximate the ice sheet model, bringing the time to produce output down to a tenth …

Seasonal Dynamics Of Dissolved Iron On The Antarctic Continental Shelf: Late-Fall Observations From The Terra Nova Bay And Ross Ice Shelf Polynyas, P. N. Sedwick, B. M. Sohst, C. O'Hara, S. E. Stammerjohn, B. Loose, M. S. Dinniman, N. J. Buck, J. A. Resing, S. F. Ackley

OES Faculty Publications

Over the Ross Sea shelf, annual primary production is limited by dissolved iron (DFe) supply. Here, a major source of DFe to surface waters is thought to be vertical resupply from the benthos, which is assumed most prevalent during winter months when katabatic winds drive sea ice formation and convective overturn in coastal polynyas, although the impact of these processes on water-column DFe distributions has not been previously documented. We collected hydrographic data and water-column samples for trace metals analysis in the Terra Nova Bay and Ross Ice Shelf polynyas during April-May 2017 (late austral fall). In the Terra Nova …

Research Sites Get Closer To Field Camps Over Time: Informing Environmental Management Through A Geospatial Analysis Of Science In The Mcmurdo Dry Valleys, Antarctica, Stephen M. Chignell, Madeline E. Myers, Adrian Howkins, Andrew Fountain

Geology Faculty Publications and Presentations

As in many parts of the world, the management of environmental science research in Antarctica relies on cost-benefit analysis of negative environmental impact versus positive scientific gain. Several studies have examined the environmental impact of Antarctic field camps, but very little work looks at how the placement of these camps influences scientific research. In this study, we integrate bibliometrics, geospatial analysis, and historical research to understand the relationship between field camp placement and scientific production in the McMurdo Dry Valleys of East Antarctica. Our analysis of the scientific corpus from 1907–2016 shows that, on average, research sites have become less …

Late Pleistocene And Early Holocene Sea-Level History And Glacial Retreat Interpreted From Shell-Bearing Marine Deposits Of Southeastern Alaska, Usa, James F. Baichtal, Alia J. Lesnek, Risa J. Carlson, Nicholas S. Schmuck, Jane L. Smith, Dennis J. Landwehr, Jason P. Briner

Publications and Research

We leverage a data set of >720 shell-bearing marine deposits throughout southeastern Alaska (USA) to develop updated relative sea-level curves that span the past ~14,000 yr. This data set includes site location, elevation, description when avail-able, and 436 14C ages, 45 of which are published here for the first time. Our sea-level curves suggest a peripheral forebulge developed west of the retreating Cordilleran Ice Sheet (CIS) margin between ca. 17,000 and 10,800 calibrated yr B.P. By 14,870 ± 630 to 12,820 ± 340 cal. yr B.P., CIS mar-gins had retreated from all of southeastern Alaska’s fjords, channels, and passages. At …

Science Is For Everybody: A Resource For Understanding Glaciers, Climate, And Modeling, Emma Watson

Independent Study Project (ISP) Collection

Climate change threatens the existence of glaciers worldwide. In order to properly interact with these changing systems, we must first understand them. Glacial models provide an excellent way to do this; however, the language and mathematical concepts used in their creation is generally inaccessible to a common audience. This project presents an online resource for a general audience to interact with climate science, glaciology, and glacial modeling. Long term goals for the project include the incorporation of a glacial model of Drangajökull, Vestfirðir, NW Iceland. As such, focus for the project includes a literature review of glaciers, Drangajökull in particular, …

Letters To A Glacier; An Experiment And Critique Of M. Jackson’S Glacier-Ruins Narrative, Lily Fife Schaeufele

Independent Study Project (ISP) Collection

“Words are events, they do things, change things. They transform both speaker and hearer; they feed energy back and forth and amplify it. They feed understanding or emotion back and forth and amplify it.” —Ursula K. Le Guin

Letters to a Glacier; The Buoy Project Isafjordur is an ongoing invitation to the people of Isafjordur to write a letter to a specific glacier in Iceland onto a collection of discarded buoys gathered from the Isafjorudur and Bolungarvik junk yards. Over a period of two days on November 9th and 10th, I actively invited customers in the local cafe Heimabyggð to …

A Case Study Using 2019 Pre-Monsoon Snow And Stream Chemistry In The Khumbu Region, Nepal, Heather M. Clifford, Mariusz Potocki, Inka Koch, Tenzing Sherpa, Mike Handley, Elena Korotkikh, Douglas Introne, Susan Kaspari, Kimberley Miner, Tom Matthews, Baker Perry, Heather Guy, Ananta Gajurel, Praveen Kumar Singh, Sandra Elvin, Aurora C. Elmore, Alex Tait, Paul A. Mayewski

Geological Sciences Faculty Scholarship

This case study provides a framework for future monitoring and evidence for human source pollution in the Khumbu region, Nepal. We analyzed the chemical composition (major ions, major/trace elements, black carbon, and stable water isotopes) of pre-monsoon stream water (4300–5250 m) and snow (5200–6665 m) samples collected from Mt. Everest, Mt. Lobuche, and the Imja Valley during the 2019 pre-monsoon season, in addition to a shallow ice core recovered from the Khumbu Glacier (5300 m). In agreement with previous work, pre-monsoon aerosol deposition is dominated by dust originating from western sources and less frequently by transport from southerly air mass …

Climate On The Blanca Massif, Sangre De Cristo Mountains, Colorado, Usa, During The Last Glacial Maximum, Keith A. Brugger, Eric M. Leonard, Kurt A. Refsnider, Peter Dolan

Geology Publications

Temperature-index modeling is used to determine the magnitude of temperature depression on the Blanca Massif, Colorado, required to maintain steady-state mass balances of nine reconstructed glaciers at their extent during the Last Glacial Maximum (LGM). The mean temperature depression thus determined is ~8.6 +0.7/−0.9 degrees C where the uncertainties account for those inherent in the glacier reconstructions, in model parameters (e.g., melt factors), and possible modest changes in LGM precipitation. Associated equilibrium-line altitudes (ELAs) exhibit a statistically significant directional dependency being lower toward the north and east. Under the assumption that regional temperature change was uniform, required changes in precipitation …

Surface Morphology And Subsurface Ice Content Relationships In Arcadia Planitia, Mars And The Canadian High Arctic, Shannon M. Hibbard

Electronic Thesis and Dissertation Repository

As NASA and SpaceX prepare for future human missions to Mars as part of an In-situ Resource Utilization (ISRU) Space Act Agreement (SAA), we need more detailed characterization of ice at proposed landing sites to constrain ice accessibility, landing safety, and scientific value. Obtaining near-surface in situ water-ice can be used for rocket fuel and life support needs which would significantly reduce the mass needed for transport to and from Mars. Arcadia Planitia is the lowest-lying region in the northern hemisphere of Mars where abundant evidence exists for an ice-rich subsurface. Shallow Radar observations indicate a decameters-thick layer of water-ice …

The Impacts Of Mid-Holocene Warming On Water Quality In A Southwestern Ontario Kettle Pond, Morgan E. Peicheff

Undergraduate Student Research Internships Conference

No abstract provided.

Quantifying Surface Changes On Mcmurdo Ice Shelf, Antarctica, Ann M. Hill

Electronic Theses and Dissertations

The amount of ice stored in Antarctica has the potential to raise sea level by almost 60 meters. Mass is primarily lost through glaciers draining the ice sheet and flowing into and ice shelves. Ice shelves float on the ocean and act as a resisting force to the flow of the glaciers, thereby modulating the flow of tributary glaciers, and consequently glacier contribution to global sea level rise. McMurdo Ice Shelf (MIS) buttresses four tributary glaciers, three of which will be discussed in this thesis, as well as the northwest corner of the faster flowing Ross Ice Shelf, which has …

Modern And Paleo Perspectives On The Role Of The Westerlies In Glaciation, Alexander Audet

Electronic Theses and Dissertations

Deciphering causes of glaciations and their abrupt terminations over the last >700,000 yrs remains an important problem for understanding the behavior of the climate system and how it might change in the future. In particular, the role of the Southern Hemisphere (SH) Westerlies in global change has arisen as an important research direction. Glaciers are highly sensitive to climate change. Examination of mid-latitude glaciers under the influence of westerly wind systems in both hemispheres can help provide insight into the role of the Westerlies in climate change. In this thesis, I present a twofold strategy to refine knowledge of the …