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Physical Sciences and Mathematics

2015

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Articles 1 - 30 of 131

Full-Text Articles in Geography

Spatial 2015, Werner Kuhn, Matt Duckham, Marcia Castro Dec 2015

Spatial 2015, Werner Kuhn, Matt Duckham, Marcia Castro

Journal of Spatial Information Science

This report summarizes the first in a new series of interdisciplinary unconferences, called SPATIAL. SPATIAL 2015 was focused on applying spatial information to human health, and was held at the Center for Spatial Studies at the University of California, Santa Barbara, 9-11 December 2015.


Spatial Refinement As Collection Order Relations, Zhong Zhao Dec 2015

Spatial Refinement As Collection Order Relations, Zhong Zhao

Journal of Spatial Information Science

An abstract examination of refinement (and conversely, coarsening) with respect to the involved spatial relations gives rise to formulated order relations between spatial coverings, which are defined as complete-coverage representations composed of regional granules. Coverings, which generalize partitions by allowing granules to overlap, enhance hierarchical geocomputations in several ways. Refinement between spatial coverings has underlying patterns with respect to inclusion—formalized as binary topological relations—between their granules. The patterns are captured by collection relations of inclusion, which are obtained by constraining relevant topological relations with cardinality properties such as uniqueness and totality. Conjoining relevant collection relations of equality and proper inclusion …


Routes Visualization: Automated Placement Of Multiple Route Symbols Along A Physical Network Infrastructure, Jules Teulade-Denantes, Adrien Maudet, Cécile Duchêne Dec 2015

Routes Visualization: Automated Placement Of Multiple Route Symbols Along A Physical Network Infrastructure, Jules Teulade-Denantes, Adrien Maudet, Cécile Duchêne

Journal of Spatial Information Science

This paper tackles the representation of routes carried by a physical network infrastructure on a map. In particular, the paper examines the case where each route is represented by a separate colored linear symbol offset from the physical network segments and from other routes---as on public transit maps with bus routes offset from roads. In this study, the objective is to automate the placement of such route symbols while maximizing their legibility, especially at junctions. The problem is modeled as a constraint optimization problem. Legibility criteria are identified and formalized as constraints to optimize, while focusing on the case of …


Invariant Spatial Information In Sketch Maps — A Study Of Survey Sketch Maps Of Urban Areas, Jia Wang, Angela Schwering Dec 2015

Invariant Spatial Information In Sketch Maps — A Study Of Survey Sketch Maps Of Urban Areas, Jia Wang, Angela Schwering

Journal of Spatial Information Science

It is commonly recognized that free-hand sketch maps are influenced by cognitive impacts and therefore sketch maps are incomplete, distorted, and schematized. This makes it difficult to achieve a one-to-one alignment between a sketch map and its corresponding geo-referenced metric map. Nevertheless, sketch maps are still useful to communicate spatial knowledge, indicating that sketch maps contain certain spatial information that is robust to cognitive impacts. In existing studies, sketch maps are used frequently to measure cognitive maps. However, little work has been done on invariant spatial information in sketch maps, which is the information of spatial configurations representing correctly the …


Development And Evaluation Of A Geographic Information Retrieval System Using Fine Grained Toponyms, Damien Palacio, Curdin Derungs, Ross S. Purves Dec 2015

Development And Evaluation Of A Geographic Information Retrieval System Using Fine Grained Toponyms, Damien Palacio, Curdin Derungs, Ross S. Purves

Journal of Spatial Information Science

Geographic information retrieval (GIR) is concerned with returning information in response to an information need, typically expressed in terms of a thematic and spatial component linked by a spatial relationship. However, evaluation initiatives have often failed to show significant differences between simple text baselines and more complex spatially enabled GIR approaches. We explore the effectiveness of three systems (a text baseline, spatial query expansion, and a full GIR system utilizing both text and spatial indexes) at retrieving documents from a corpus describing mountaineering expeditions, centred around fine grained toponyms. To allow evaluation, we use user generated content (UGC) in the …


Spatial Analysis Of Distributions And Habitat Conditions Of Fallopia Japonica (Japanese Knotweed) Invasive Species Applying Unmanned Helicopter Remote Sensing, Jiazhen Zhang Dec 2015

Spatial Analysis Of Distributions And Habitat Conditions Of Fallopia Japonica (Japanese Knotweed) Invasive Species Applying Unmanned Helicopter Remote Sensing, Jiazhen Zhang

Great Lakes Center Masters Theses

Abstract:

Fallopia japonica (Japanese knotweed) is a perennial herbaceous plant that is native to East Asia. It is considered as one of the worst invasive species worldwide because of its serious impact on biological diversity and human activities (Lowe et al., 2001). Once established, Japanese knotweed forms dense stands that shade and crowd out native plant species. The objectives of this research were to verify and confirm the distribution of Japanese knotweed as published online by the New York Department of Environmental Conservation (DEC) – iMap and to identify the geographic areas of spreading and the local habitat conditions. In …


Estimating The Water Quality Condition Of River And Lake Water In The Midwestern United States From Its Spectral Characteristics, Jing Tan Dec 2015

Estimating The Water Quality Condition Of River And Lake Water In The Midwestern United States From Its Spectral Characteristics, Jing Tan

Open Access Dissertations

This study focuses on developing/calibrating remote sensing algorithms for water quality retrieval in Midwestern rivers and lakes. In the first part of this study, the spectral measurements collected using a hand-held spectrometer as well as water quality observations for the Wabash River and its tributary the Tippecanoe River in Indiana were used to develop empirical models for the retrieval of chlorophyll (chl) and total suspended solids (TSS). A method for removing sky and sun glint from field spectra for turbid inland waters was developed and tested. Empirical models were then developed using a subset of the field measurements with the …


Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy Dec 2015

Thermodynamic Modeling Of Aqueous Geochemistry Of Chlorine Salts: Application To Stability And Habitability Of Liquid Brines On Mars, Amira Elsenousy

Graduate Theses and Dissertations

The WCL (Wet Chemistry Lab) instrument on board the Mars’s Phoenix Lander has identified the soluble ionic composition of the soil at the landing site. Two important ions were detected at the landing site; perchlorates (ClO4-) with a concentration of ~ 2.4 wt% and chlorides (Cl-) with a concentration of 0.54 wt%. Between chloride and perchlorate ions three other oxidized ions exist and called chlorine ions: hypochlorite ClO - (ox. state +1), chlorite ClO2- (ox. state +3) and chlorate ClO3- (ox. state +5). These oxidized ions might be existed as intermediate species on the surface of Mars but remained undetected. …


Predictive Modeling Of Terrestrial Radiation Exposure From Geologic Materials, Daniel A. Haber Dec 2015

Predictive Modeling Of Terrestrial Radiation Exposure From Geologic Materials, Daniel A. Haber

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aerial gamma ray surveys are an important tool for national security, scientific, and industrial interests in determining locations of both anthropogenic and natural sources of radioactivity. There is a relationship between radioactivity and geology and in the past this relationship has been used to predict geology from an aerial survey. The purpose of this project

is to develop a method to predict the radiologic exposure rate of the geologic materials in an area by creating a model using geologic data, images from the Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER), geochemical data, and pre-existing low spatial resolution aerial surveys …


Climb To The Ice, Richard Vaughan Nov 2015

Climb To The Ice, Richard Vaughan

Richard Vaughan

The article, originally presented as a lecture, discusses George Bird Grinnell's 1887 climb of the Montana glacier that eventually become known as Grinnell Glacier. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell's previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author. Originally delivered as a lecture at the Montana History Conference, October 2, 2010. Full issue available at: http://issuu.com/um_crown_gye/docs/crownofthecontinent-autumn2012


To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan Nov 2015

To The Ice: George Bird Grinnell's 1887 Ascent Of Grinnell Glacier, Richard Vaughan

Richard Vaughan

This article discusses a climbing expedition undertaken by U.S. conservationist George Bird Grinnell to ascend what would come to be known as Grinnell Glacier in Montana. Grinnell’s efforts to establish Glacier National Park are detailed. Grinnell’s previously unpublished descriptions of the glacier and its surrounding area are analyzed by the author.


Gis-Integrated Mathematical Modeling Of Social Phenomena At Macro- And Micro- Levels—A Multivariate Geographically-Weighted Regression Model For Identifying Locations Vulnerable To Hosting Terrorist Safe-Houses: France As Case Study, Elyktra Eisman Nov 2015

Gis-Integrated Mathematical Modeling Of Social Phenomena At Macro- And Micro- Levels—A Multivariate Geographically-Weighted Regression Model For Identifying Locations Vulnerable To Hosting Terrorist Safe-Houses: France As Case Study, Elyktra Eisman

FIU Electronic Theses and Dissertations

Adaptability and invisibility are hallmarks of modern terrorism, and keeping pace with its dynamic nature presents a serious challenge for societies throughout the world. Innovations in computer science have incorporated applied mathematics to develop a wide array of predictive models to support the variety of approaches to counterterrorism. Predictive models are usually designed to forecast the location of attacks. Although this may protect individual structures or locations, it does not reduce the threat—it merely changes the target. While predictive models dedicated to events or social relationships receive much attention where the mathematical and social science communities intersect, models dedicated to …


A Study On The Integration Of Multivariate Metocean, Ocean Circulation, And Trajectory Modeling Data With Static Geographic Information Systems For Better Marine Resources Management And Protection During Coastal Oil Spill Response – A Case Study And Gap Analysis On Northeastern Gulf Of Mexico Tidal Inlets, Richard Ray Knudsen Nov 2015

A Study On The Integration Of Multivariate Metocean, Ocean Circulation, And Trajectory Modeling Data With Static Geographic Information Systems For Better Marine Resources Management And Protection During Coastal Oil Spill Response – A Case Study And Gap Analysis On Northeastern Gulf Of Mexico Tidal Inlets, Richard Ray Knudsen

USF Tampa Graduate Theses and Dissertations

The Oil Pollution Act of 1990 requires the development of Regional and Area Contingency Plans. For more than 20 years, the State of Florida, under both the Department of Environmental Protection and the Florida Fish and Wildlife Commission, has worked closely with the U.S. Coast Guard and the National Oceanic and Atmospheric Administration to develop these plans for coastal and marine oil spill response. Current plans, developed with local, state and federal stakeholder input, use geographic information systems (GIS) data such as location and extent of sensitive ecological, wildlife, and human-use features (termed Environmental Sensitivity Index data), pre-defined protection priorities, …


Is Nubia Plate Rigid? A Geodetic Study Of The Relative Motion Of Different Cratonic Areas Within Africa., Mary Wambui Njoroge Nov 2015

Is Nubia Plate Rigid? A Geodetic Study Of The Relative Motion Of Different Cratonic Areas Within Africa., Mary Wambui Njoroge

USF Tampa Graduate Theses and Dissertations

The Nubia plate is normally considered to be a rigid plate and as such used in the realization of terrestrial reference frame. Gondwana breakup plate reconstruction, the Cameroon volcanic line, seismicity, and the morphology of the Okavango rift zone (ORZ) suggest the presence of internal deformation within the Nubia plate. To test this hypothesis, six different reference frames were developed from the velocity field of three individual regions (West, Central and South), and of different combinations of them (West+Central, South+Central, and Nubia as a whole). The residual velocities with respect to these references frame help us understand the presence of …


Tracking Of Karst Contamination Using Alternative Monitoring Technologies: Hidden River Cave Kentucky, Caren Raedts, Christopher Smart Oct 2015

Tracking Of Karst Contamination Using Alternative Monitoring Technologies: Hidden River Cave Kentucky, Caren Raedts, Christopher Smart

Sinkhole Conference 2015

Karst groundwater contamination presents great challenges for efficient monitoring because of rapid, discrete transport and the diversity of contaminants. Here a low cost approach is described and applied to Hidden River Cave, Kentucky, where a long history of contamination has been experienced. Local knowledge was acquired through informal interviews and coupled with observations of contaminant residues, faunal distributions and fluorescence spectra in the cave. The resulting patterns were interpreted using Google Earth and Street View to identify specific contaminant sources in the affected sub-catchment of the cave. Despite success in matching contaminant sources with the contamination history and pattern, the …


Using Future Benefits To Set Conservation Priorities For Wetlands, Samuel B. Merrill Oct 2015

Using Future Benefits To Set Conservation Priorities For Wetlands, Samuel B. Merrill

Journal of Ocean and Coastal Economics

In an era of rising sea levels, costal land managers including land trust representatives, municipal planners, and others contributing to decisions about whether to develop or protect coastal parcels do not have viable means of evaluating future values on wetlands that will be created when sea levels rise. This project develops and tests a software modeling approach to help address this issue, in combination with a novel, expert-opinion driven benefit-cost framework. The beta test used three parcels in Scarborough, Maine: Hampton Circle, Maine Audubon, and Pine Point. It used a group of experts to 1) allocate initial values to these …


Short-Tailed Temperature Distributions Over North America And Implications For Future Changes In Extremes, Paul C. Loikith, J. David Neelin Oct 2015

Short-Tailed Temperature Distributions Over North America And Implications For Future Changes In Extremes, Paul C. Loikith, J. David Neelin

Geography Faculty Publications and Presentations

Some regions of North America exhibit nonnormal temperature distributions. Shorter-than-Gaussian warm tails are a special subset of these cases, with potentially meaningful implications for future changes in extreme warm temperatures under anthropogenic global warming. Locations exhibiting shorter-than-Gaussian warm tails would experience a greater increase in extreme warm temperature exceedances than a location with a Gaussian or long warm-side tail under a simple uniform warm shift in the distribution. Here we identify regions exhibiting such behavior over North America and demonstrate the effect of a simple warm shift on changes in extreme warm temperature exceedances. Some locations exceed the 95th percentile …


Crowdsourcing Global Wastewater Data, Don Mosteller, Sam Cohen, Cory Nestor, Angel Hsu, Omar Malik Sep 2015

Crowdsourcing Global Wastewater Data, Don Mosteller, Sam Cohen, Cory Nestor, Angel Hsu, Omar Malik

Yale Day of Data

No time to waste: Crowdsourcing global wastewater treatment data

Worldwide, over 80 percent of wastewater is discharged into water bodies without undergoing treatment, severely impairing human well-being and ecosystem vitality along the way. National performance on wastewater treatment is difficult to quantify and is poorly understood due to a lack of common definitions, poor data collection standards, and limited historical data. To address this, the Yale Environmental Performance Index (EPI), a research group that produces a biennial ranking of country-level environmental performance, developed a first-of-its kind national wastewater treatment indicator.[1]

The indicator assesses wastewater treatment performance for 183 countries, …


A Multilevel Analysis Of Neighborhood Socioeconomic Effect On Preterm Births In Georgia, Usa, Wei Tu, Jun Tu, Stuart H. Tedders Sep 2015

A Multilevel Analysis Of Neighborhood Socioeconomic Effect On Preterm Births In Georgia, Usa, Wei Tu, Jun Tu, Stuart H. Tedders

School of Earth, Environment, and Sustainability Faculty Publications

This study estimates the neighborhood socioeconomic status (SES) effect on the risk of preterm birth (PTB) using multilevel regression (MLR) models. Birth data retrieved from year 2000 and 2010 Georgia Vital Records were linked to their respective census tracts. Principle component analysis (PCA) was performed on nine selected census variables and the first two principal components (Fac1 and Fac2) were used to represent the neighborhood-level SES in the MLR models. Two-level random intercept MLR models were specified using 122,744 and 112,578 live and singleton births at the individual level and 1613 and 1952 census tracts at the neighborhood level, for …


Performance Of High Resolution Satellite Rainfall Products Over Data Scarce Parts Of Eastern Ethiopia, Shimelis B. Gebere, Tena Alamirew, Broder J. Merkel, Assefa M. Melesse Sep 2015

Performance Of High Resolution Satellite Rainfall Products Over Data Scarce Parts Of Eastern Ethiopia, Shimelis B. Gebere, Tena Alamirew, Broder J. Merkel, Assefa M. Melesse

Department of Earth and Environment

Accurate estimation of rainfall in mountainous areas is necessary for various water resource-related applications. Though rain gauges accurately measure rainfall, they are rarely found in mountainous regions and satellite rainfall data can be used as an alternative source over these regions. This study evaluated the performance of three high-resolution satellite rainfall products, the Tropical Rainfall Measuring Mission (TRMM 3B42), the Global Satellite Mapping of Precipitation (GSMaP_MVK+), and the Precipitation Estimation from Remotely-Sensed Information using Artificial Neural Networks (PERSIANN) at daily, monthly, and seasonal time scales against rain gauge records over data-scarce parts of Eastern Ethiopia. TRMM 3B42 rain products show …


Heirloom: A Piper's Orchard Abecadarian, Shin Yu Pai Sep 2015

Heirloom: A Piper's Orchard Abecadarian, Shin Yu Pai

The Goose

Poetry by Shin Yu Pai


Prescribed Fire Monitoring Report, Tallgrass Prairie National Preserve 2014 (Iqcs Fire Number 285382, 285383, 266782, 285677), Sherry A. Leis, Sarah E. Hinman Sep 2015

Prescribed Fire Monitoring Report, Tallgrass Prairie National Preserve 2014 (Iqcs Fire Number 285382, 285383, 266782, 285677), Sherry A. Leis, Sarah E. Hinman

United States National Park Service: Publications

Introduction

In 2014, the preserve’s federal and NGO partners conducted prescribed fires during March, April, and October that encompassed 8129.8 acres of Tallgrass Prairie National Preserve (TAPR). This was a unique burn year in that prescribed burns occurred in the spring, the traditional burn season, and the fall. Fall burns were conducted to support needed archaeological surveys as part of the environmental compliance for a symphony event scheduled for June 2015 at the preserve. Burns at TAPR were coordinated with local US Fish and Wildlife Service (USFWS), The Nature Conservancy (TNC), and various units of the National Park Service.

Burns …


A Geospatial Tool For Wetland Prioritization At The Watershed Scale, Debra Sue Blackmore, Heejun Chang Sep 2015

A Geospatial Tool For Wetland Prioritization At The Watershed Scale, Debra Sue Blackmore, Heejun Chang

Institute for Natural Resources Publications

There is an increasing demand for assessing ecosystem functions for freshwater wetlands, especially when comparing or prioritizing among wetlands at the watershed scale. We estimated the relative potential of selected ecosystem functions for freshwater wetlands within a watershed using widely available geospatial data. We developed four functions to estimate 1) flood storage, 2) late season flow, 3) sediment retention and 4) temperature control in four pilot watersheds in Oregon (Tualatin, Coquille, Upper Grande Ronde and Sprague). These watersheds are geographically separated from each other representing diverse ecoregion environments. Spatial analysis and geographic information system (GIS) were designed for maximum re-use, …


Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin Aug 2015

Late Quaternary Speleogenesis And Landscape Evolution In A Tropical Carbonate Island: Pango La Kuumbi (Kuumbi Cave), Zanzibar, Nikos Kourampas, Ceri Shipton, William Mills, Ruth Tibesasa, Henrietta Horton, Mark Horton, Mary Prendergast, Alison Crowther, Katerina Douka, Patrick Faulkner, Llorenç Picornell, Nicole Boivin

International Journal of Speleology

Kuumbi Cave is one of a group of caves that underlie a flight of marine terraces in Pleistocene limestone in eastern Zanzibar (Indian Ocean). Drawing on the findings of geoarchaeological field survey and archaeological excavation, we discuss the formation and evolution of Kuumbi Cave and its wider littoral landscape. In the later part of the Quaternary (last ca. 250,000 years?), speleogenesis and terrace formation were driven by the interplay between glacioeustatic sea level change and crustal uplift at rates of ca. 0.10-0.20 mm/yr. Two units of backreef/reef limestone were deposited during ‘optimal’ (highest) highstands, tentatively correlated with MIS 7 and …


Spatiotemporal Wireless Sensor Network Field Approximation With Multilayer Perceptron Artificial Neural Network Models, François Neville Aug 2015

Spatiotemporal Wireless Sensor Network Field Approximation With Multilayer Perceptron Artificial Neural Network Models, François Neville

Electronic Theses and Dissertations

As sensors become increasingly compact and dependable in natural environments, spatially-distributed heterogeneous sensor network systems steadily become more pervasive. However, any environmental monitoring system must account for potential data loss due to a variety of natural and technological causes. Modeling a natural spatial region can be problematic due to spatial nonstationarities in environmental variables, and as particular regions may be subject to specific influences at different spatial scales. Relationships between processes within these regions are often ephemeral, so models designed to represent them cannot remain static. Integrating temporal factors into this model engenders further complexity.

This dissertation evaluates the use …


Quantifying Undisturbed Land In Minnesota's Prairie Coteau And Lac Qui Parle Valley Regions, Pete Bauman, Ben Carlson, Tanner Butler Aug 2015

Quantifying Undisturbed Land In Minnesota's Prairie Coteau And Lac Qui Parle Valley Regions, Pete Bauman, Ben Carlson, Tanner Butler

Quantifying Undisturbed Lands in MInnesota's Prairie Coteau and Lac qui Parle Valley Regions

We employed simple GIS methods utilizing the Minnesota Farm Service Agency’s Common Land Unit (CLU) cropland data layer from 2013, along with 2013 USDA National Agriculture Imagery Program (NAIP) county mosaic aerial imagery, to evaluate over 5 million acres of land in 14 southwest Minnesota counties, including all or portions of 10 counties within the Minnesota portion of the Prairie Coteau region and the entirety of four counties in the Lac qui Parle region. We utilized the CLU cropland layer to first identify and remove any areas with a cropping history, regardless of current land use. We then analyzed the …


A Modeling Approach To Determine The Impacts Of Land Use And Climate Change Scenarios On The Water Flux Of The Upper Mara River, L. M. Mango, Assefa Melesse, M. E. Mcclain, Daniel Gann, S. G. Setegn Aug 2015

A Modeling Approach To Determine The Impacts Of Land Use And Climate Change Scenarios On The Water Flux Of The Upper Mara River, L. M. Mango, Assefa Melesse, M. E. Mcclain, Daniel Gann, S. G. Setegn

Daniel Gann

With the flow of the Mara River becoming increasingly erratic especially in the upper reaches, attention has been directed to land use change as the major cause of this problem. The semi-distributed hydrological model Soil and Water Assessment Tool 5 (SWAT) and Landsat imagery were utilized in the upper Mara River Basin in order to 1) map existing field scale land use practices in order to determine their impact 2) determine the impacts of land use change on water flux; and 3) determine the impacts of rainfall (0%, ±10% and ±20%) and air temperature variations (0% and +5%) based on …


Transportation And Sanitation Drivers Of Land Use/Land Cover Change: Loss Of The Jamaica Bay Wetlands, Margaret Joy Cytryn Aug 2015

Transportation And Sanitation Drivers Of Land Use/Land Cover Change: Loss Of The Jamaica Bay Wetlands, Margaret Joy Cytryn

Theses and Dissertations

This thesis presents an analysis (1830-2014) of the historical events of land use/land cover change in the Jamaica Bay estuary, identification of the agents of change, and a perspective on the potential drivers of transportation and sanitation in land use/land cover change.


An Analysis Of Spatio-Temporal Landscape Patterns For Protected Areas In Northern New England: 1099-2010, Spencer Meyer, Mary-Kate Beard-Tisdale, Christopher S. Cronan, Robert Lilieholm Aug 2015

An Analysis Of Spatio-Temporal Landscape Patterns For Protected Areas In Northern New England: 1099-2010, Spencer Meyer, Mary-Kate Beard-Tisdale, Christopher S. Cronan, Robert Lilieholm

Publications

Context: Landscape ecology theory provides insight about how large assemblages of protected areas (PAs) should be configured to protect biodiversity. We adapted these theories to evaluate whether the emergence of decentralized land protection in a largely private landscape followed the principles of reserve design. Objectives: Our objectives were to determine: (1) Are there distinct clusters of PAs in time and space? (2) Are PAs becoming more spatially clustered through time? and (3) Does the resulting PA portfolio have traits characteristic of ideal reserve design? Methods: We developed an historical dataset of the PAs enacted since 1900 in the northern New …


Establishing A Chronology Of Late Quaternary Glacial Advances In The Cordillera De Talamanca, Costa Rica, Rebecca Susan Potter Aug 2015

Establishing A Chronology Of Late Quaternary Glacial Advances In The Cordillera De Talamanca, Costa Rica, Rebecca Susan Potter

Masters Theses

Little research has focused on glacial events in the tropics. Providing an absolute glacial chronology in Costa Rica will build a foundation for future glacial chronologies and paleoclimate reconstructions in the highlands of Central America. Evidence of past glaciation, including moraines and glacial lakes, is preserved within formerly glaciated valleys in the Cordillera de Talamanca. Orvis and Horn (2000) constrained deglaciation ages of the most recent glacial event in the Cordillera de Talamanca based on radiocarbon dates of glacial lake sediments. Radiocarbon ages indicated complete deglaciation after 12.4 ka cal BP but before 9.7 ka cal BP (Orvis and Horn, …