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Comstock Point, Lubec, Maine - A Natural And Photographic History, Willaim H. Schlesinger, Lisa M. Dellwo

Documents from Environmental Organizations

A natural and photographic history of our lands compiled by Lisa Dellwo and Bill Schlesinger, with the help of many friends and neighbors.

Kinematic Vorticity And Porphyroclast Rotation In Mylonites Of The Norumbega Fault System: Implications For Paleoviscometry, Hendrik Lenferink

Honors College

Crystallographic and shape preferred orientation (SPO) fabrics that develop in mylonitic shear zones can preserve the mean kinematic vorticity number (Wm) of bulk flow. Microstructural methods exploiting dynamically recrystallized quartz and porphyroclast SPO fabrics typically yield conflicting values of Wm. The Sandhill Corner Mylonite Zone of the Norumbega Fault System, Maine, USA, serves as a case study for investigating this discrepancy; Wm estimates range from 0.90 to 1.00 employing the former method (Method 1) and from 0.3 to 0.6 employing the latter method (Method 2). Using a numerical model, I show how a low-viscosity layer (LVL) surrounding clasts affects their …

Stratigraphic Architecture Of Pozuelo Mounds As Revealed By Earth Resistivity Tomography, Caeli Connolly

Honors College

This study is a geoarchaeological analysis using earth resistance tomography (ERT) surveys of two of four mounds at Pozuelo (Formative Period, cal yr 3000 BP) in the Chincha Valley of coastal, southern Peru. Layers identified in the subsurface were to determine the presence or absence of regional continuity between the mounds. This effort is part of a larger investigation examining the paleoenvironmental setting of the site, and its influence on site location and use. Ten earth resistance tomography profiles were collected using an ABEM Terrameter LS2 and 81 pin array. These profiles were then topographically corrected using topographic survey data …

Lethal And Sublethal Effects Of Beauveria Bassiana On Maine Ticks Across Soil Ph, Alexander Mahar

Honors College

Ticks are obligate parasite arthropods that are becoming increasingly common in northern regions of the United States. Ticks such as the black-legged tick (Ixodes scapularis) and the American dog tick (Dermacentor variabilis) are vectors for pathogens that cause a wide range of diseases, and as these ticks increase their exposure to humans, the diseases they transmit become more prevalent. This upward trend in cases of tick-borne illnesses has necessitated the pursuit of tick control methods that can be used across the diverse environments that are present in tick habitat ranges. One such control method is the fungal biological control, Beauveria …

Assessing College Students' Understanding Of Geologic Timescales, Ethan Couture

Honors College

Geologic timescales are central to many concepts in the natural sciences, including evolution, climate change and plate tectonics. However, geologic time scales can be challenging to appreciate, especially for those who have not had exposure to such topics previously. During primary and secondary education (K-12) students are provided with foundational information about geology that is then further developed in specialized classes in college. Yet most students are not getting this foundation, which could arguably lead to deficits in their post-secondary education. Despite the importance of these concepts, especially for those interested in careers associated with geologic timescales, there have been …

Modeling Franconia Ridge, New Hampshire Using Structure From Motion And Developing New Techniques For Fracture Detection, Dane Johnson

Honors College

Bedrock fracture density is an important characteristic of bedrock that determines its structural formation, the potential for groundwater or fluid flow, and the capacity of erosion for exposed features. In the case of the Franconia Range, there are two primary bedrock lithologies that we wish to analyze. In this research, we conduct the first structural analysis and quantification of the bedrock fracture density of this region using Structure from Motion modeling and machine learning algorithms. Additionally, the algorithms were supplemented to be useful in determining fracture density in the subsurface geology of Ground-Penetrating-Radar (GPR) radargrams. The products of this work …

Arcmap Basics: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document is a quick guide to performing common geospatial tasks in ArcMap 10.x (ArcGIS Desktop) for new users. Covered are basic navigation of the ArcMap window; importing, opening, querying, editing, and exporting data; and map preparation. In many cases, there are multiple ways to accomplish different tasks; presented here are the methods the author finds easiest or most straightforward. Mouse click sequences and menu/tool layout may differ if using previous versions of ArcMap.

Riders On The Storm: Using Satellite Transmitters To Quantify American Woodcock Movement Behavior Following Extreme Weather Events, Katherine Trebilcock

Honors College

The American Woodcock (Scolopax minor) has experienced steady declines in abundance over the past fifty years, which has raised questions as to why (Sauer et al. 1991). Migration for many birds, woodcock included, is energetically intensive, and may be the cause for greater mortality compared to other times of the year (Newton 2007). Despite this, there remains uncertainty in how conditions encountered during migration affect their movements and survival. One obstacle that birds must face is extreme weather, which has been increasing in intensity and occurrence due to climate change. How these events impact a migrating woodcock has been speculated …

S6e6: How Do Changing Conditions In The Arctic Affect Maine?, Ron Lisnet, Karl Kreutz, Kristin Schild

The Maine Question

Changes in the Arctic affect Maine, despite them being separated by more than 1,000 miles. Several scientists from the University of Maine study these shifting conditions of the climate and environment in the region and their impacts. In 2018, the UMaine Arctic Initiative was formed to build on their work and enhance collaboration in the campus community and with outside stakeholders.

In this episode of “The Maine Question” podcast, scientists Karl Kreutz and Kristin Schild from UMaine Arctic and the UMaine Climate Change Institute discuss their research, and elaborate on the region and its shifting conditions influence the state.

Arcmap Hydrology Toolset: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides guidance for performing hydrologic tasks using the Hydrology Toolset in ArcMap 10.x (ArcGIS Desktop). Covered here are an overview of the uses and limitations of the tools within the Hydrology Toolset, related tools from from additional ArcGIS toolsets, and step-by-step instructions for hydrologic workflows including digital elevation model (DEM) preparation, pit fill detection, "burning in" culverts for proper flow path routing, watershed and stream network delineation, and flow network statistics.

Survey Control With Gnss Receiver: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document is a quick guide to establishing survey control points using a Global Navigation Satellite Systems (GNSS) receiver and processing collected point coordinate data.

The WPES Research Group uses a Trimble NetR9 GNSS reference receiver, which is reflected in the specific sequences of button presses outlined in the data profile setup, field operation, and data download sections. Readers using a different receiver may still find the general workflow overview useful and should be able to use the data post-processing section directly.

Total Station Field Surveying: Wpes, How Do I...? Quick Guide, Bea E. Van Dam

Non-Thesis Student Work

This document provides step-by-step guidance for performing surveys of field sites using a total station unit (TSU) and connected handheld data collector and for downloading collected point data. WPES uses a Sokkia CX-series TSU and a data collector running Carlson SurvCE software. Minor differences in instrument set-up may arise if using a different TSU. Major differences in data collection procedures will occur if using a different data collection software.

A Practical Solution: The Anthropocene Is A Geological Event, Not A Formal Epoch, Philip L. Gibbard, Andrew M. Bauer, Matthew Edgeworth, William F. Ruddiman, Jacquelyn L. Gill, Dorothy J. Merritts, Stanley C. Finney, Lucy E. Edwards, Michael J. C. Walker, Mark Maslin, Erle C. Ellis

Biology and Ecology Faculty Scholarship

The Anthropocene has yet to be defined in a way that is functional both to the international geological community and to the broader fields of environmental and social sciences. Formally defining the Anthropocene as a chronostratigraphical series and geochronological epoch with a precise global start date would drastically reduce the Anthropocene’s utility across disciplines. Instead, we propose the Anthropocene be defined as a geological event, thereby facilitating a robust geological definition linked with a scholarly framework more useful to and congruent with the many disciplines engaging with human-environment interactions. Unlike formal epochal definitions, geological events can recognize the spatial and …

Glaciology, Geomorphology Giant Roger Hooke Passes Away At 82, Division Of Marketing And Communications

General University of Maine Publications

Roger Hooke, beloved University of Maine mentor and researcher and giant in the fields of glaciology and geomorphology, died March 10 [2021] at the age of 82.

Hooke joined the School of Earth and Climate Sciences and Climate Change Institute in 2000 as a research professor and adviser. One of Hooke's interests during his time at UMaine involved examining what glacial landforms in Maine revealed about the Laurentide Ice Sheet.

Scientific Assessment Of Climate Change And Its Effects In Maine, Maine Climate Council Scientific And Technical Subcommittee, Ivan Fernandez, Robert Marvinney, Susie Arnold, Linda Bacon, Andrew Barton, Brian Beal, Sean Birkel, Russell Black, Alix Contosta, Amanda Cross, Adam Daigneault, Thomas Danielson, Stephen Dickson, Jeanne Difranco, Susan Elias, Glenn Hodgkins, Brian Hubbell, Joe Kelley, Rick Kersbergen, Glen Koehler, Rebecca Lincoln, William Livingston, Pamela Lombard, Bradfield Lyon, Andrew Pershing, Nichole Price, Jonathan Rubin, Joseph Salisbury, Erin Simons-Legaard, Peter Slovinsky, Robert Steneck, Sally Stockwell, Richard Wahle, Jay Wason, Aaron Weiskittel, Carl Wilson

Climate Change

Climate change has already made its presence known in Maine, from shorter winters and warmer summers with ocean heat waves, to stronger storms, new species showing up in our backyards and the Gulf of Maine, aquatic algal blooms, acidic ocean waters that affect shellfish, and new pests and diseases that harm our iconic forests and fisheries.

The health of Maine people is also being affected by climate change, from high heat index days driving increased emergency room visits to the ravages of Lyme and other vector-borne diseases. And our economy is feeling the effects, too — with farmers trying to …

Distribution Of First Row Transition Elements In Eclogites, Natalie Harmon

Honors College

Surficial materials are recycled back into the deep Earth at subduction zones. The oxidation state of subducted materials affects the oxidation state of major geochemical reservoirs in the Earth, such as the mantle and the crust. First row transition elements (FRTEs), such as V and Sc, are highly redox sensitive and thus have the potential to track important redox processes in subduction zones. In this project, concentrations of FRTEs in garnet, omphacite, and rutile were determined for a global suite of oceanic eclogites, which represent exhumed subducted materials. Data were collected by LA-ICP-MS using an ESI NWR193UC laser ablation system …

Estimating Bedrock Fracture Density Of The Juneau Icefield, Ak, To Inform Glacial Erosion Models, Colby Rand

Honors College

Understanding glacial erosion rates is important because debris eroded by a glacier can impact glacier flow speeds, protect tidewater glaciers from rapid retreat, and impact the productivity of marine ecosystems. Traditionally, glacial erosion models rely on a rock’s inherent “erodibility”, typically presented as a constant, to predict how much debris will be eroded by the glacier. However, the erodibility of bedrock varies spatially as a function of its fracture density, fracture orientation, and lithology, so the notion of applying a constant erodibility term to a whole field site does not fully capture the actual bedrock dynamics of the system. In …

The Microstructural Heterogeneity Of Ice In Jarvis Glacier, Alaska, Renée Clavette

Honors College

Glacier ice behaves as a viscous fluid, where flow is controlled by a number of external and internal processes. One crucial, yet sometimes overlooked, factor is ice microstructure. Studies have shown that ice crystal (grain) size, shape, and orientation influence the viscous strength of ice, and therefore its resistance to flow and deformation. Glacier flow is also impacted by friction at the bed and lateral margins. The magnitude of flow resistance due to the lateral margins is not well quantified. The goal of this overall project is to evaluate how heterogeneous optical properties of ice are that are influenced by …

Interglacial Expansion Of Alpine Glaciers In Garwood Valley, Antarctica, Laura Mattas

Honors College

It is important to understand the response of the Antarctic Ice Sheet (AIS) to ongoing global atmospheric and oceanic warming to anticipate future sea-level change. There are several contrasting views in this regard. Harig and Simons (2015) concur with the IPCC (2013) conclusion that, in recent decades, outflow across the peripheral grounding lines of the ice sheet has exceeded increased accumulation on the interior surface of the ice sheet. In contrast, Zwally et al. (2015) suggest that recent surface accumulation in the interior East and West Antarctica has outpaced peripheral losses. They further suggest that this recent positive imbalance adds …

How Acidic Sediments And Seawater Affect Interactive Effects Of Predation On Survival, Growth, And Recruitment Of Wild And Cultured Soft-Shell Clams, Mya Arenaria L., Along A Tidal Gradient At Two Intertidal Sites In Eastern Maine, Brian F. Beal, William Otto

Miscellaneous Publications

No abstract provided.

Recovering Legacy Geological Data Into A Geospatial Database Product: An Example From Baja California Norte, MéXico, Alexander C. Audet

Honors College

This project develops a workflow for the extraction of legacy geological map data using a case study in the Baja California Norte, México by four workers over forty years. This project is unique from other digitization efforts worldwide because the data were already in an unregistered vector format, instead of a raster format. Thus, the methodology used in this project took advantage of this digital format by writing arcpy scripts for use inside of ArcMap, and using database feature manipulation software, in order to streamline the data extraction process, with the goal being to develop methods for dealing with other …

High Net Loss Of Intertidal Wetland Coverage In A Maine Estuary By Year 2100, Jack R. Mclachlan

Biology and Ecology Faculty Scholarship

Rising sea levels and coastal land use are predicted to synergistically impact coastal wetlands by reducing their extent and ecosystem functioning through a process known as “coastal squeeze”. Impervious surfaces associated with coastal development prevent the natural process of wetland migration, whereby intertidal wetland area is lost at its seaward edge to rising low water lines, but is replaced by eroding uplands and accumulating new wetland at its landward edge. As these constructed surfaces prevent the replacement of lost wetland, intertidal wetlands are “squeezed” by rising sea levels until they disappear. This study uses geographic information system (GIS) to predict …

Increasing The Resolution Of The Last Glacial Maximum Record In The Tropical Andes Using 10be Cosmogenic Surface-Exposure Dating In The Cordillera Carabaya, Peru, Zachary E. Mason

Honors College

Owing to the abundance of heat and moisture, the tropics is a fundamental component of the global climate system. Yet the role of the tropics in climate remains poorly understood. The Andes are home to ~95% of all tropical glaciers, making this the ideal region for studying relationships between tropical glaciers and climate. I conducted a Beryllium-10 surface exposure dating experiment using ten quartz-bearing rock samples from a series of last glacial maximum (LGM) moraines in the Minas Tira glaciofluvial valley system, Cordillera Carabaya, Peru. The AMS measured sample dates (excluding outliers) range from 24.3 ± 0.5 ka to 19.4 …

Integrated Analytical-Computational Analysis Of Microstructural Influences On Seismic Anisotropy, Scott E. Johnson, Christopher Gerbi, Andrew J. Goupee, Senthil Vel

University of Maine Office of Research Administration: Grant Reports

The magnitudes, orientations and spatial distributions of elastic anisotropy in Earth's crust and mantle carry valuable information about gradients in thermal, mechanical and kinematic parameters arising from mantle convection, mantle-crust coupling and tectonic plate interactions. Relating seismic signals to deformation regimes requires knowledge of the elastic signatures (bulk stiffnesses) of different microstructures that characterize specific deformation environments, but the influence of microstructural heterogeneity on bulk stiffness has not been comprehensively evaluated. The objectives of this project are to: (1) scale up a preliminary method to determine the bulk stiffness of rocks using integrated analytical (electron backscatter diffraction) and computational (asymptotic …

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 …

Collaborative Research: Historic Perspectives On Climate And Biogeography From Deep-Sea Corals In The Drake Passage, Rhian G. Waller

University of Maine Office of Research Administration: Grant Reports

Polar oceans are the main sites of deep-water formation and are critical to the exchange of heat and carbon between the deep ocean and the atmosphere. This award "Historic perspectives on climate and biogeography from deep-sea corals in the Drake Passage" will address the following specific research questions: What was the radiocarbon content of the Southern Ocean during the last glacial maximum and during past rapid climate change events? and What are the major controls on the past and present distribution of cold-water corals within the Drake Passage and adjacent continental shelves? Testing these overall questions will allow the researchers …

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: A Reaction Kinetics Database For Modeling Biogeochemical Systems, Amanda A. Olsen

University of Maine Office of Research Administration: Grant Reports

Understanding how quickly environmental reactions take place is the goal of EarthKin, a geochemical database focusing on the rates of geochemical reactions. EarthKin scientists from University of Maine, Penn State, Columbia, and Saint Francis University will compile existing reaction rates into a one-stop database that will allow access to researchers working on a diverse range of projects ranging from removing carbon dioxide from the atmosphere and permanently storing it beneath the ground to cleaning up contaminated environmental sites. When completed EarthKin will be available to scientists free via the web at www.earthchem.org. Not only will we compile existing data, but …

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, …