Geography Commons^™

Numerical Simulation Of “An American Haboob”, A. Vukovic, M. Vujadinovic, G. Pejanovic, J. Andric, M. J. Kumjian, V. Djurdjevic, M. Dacic, Anup K. Prasad, Hesham El-Askary, B. C. Paris, S. Petkovic, W. Sprigg, S. Nickovic

Mathematics, Physics, and Computer Science Faculty Articles and Research

A dust storm of fearful proportions hit Phoenix in the early evening hours of 5 July 2011. This storm, an American haboob, was predicted hours in advance because numerical, land–atmosphere modeling, computing power and remote sensing of dust events have improved greatly over the past decade. High-resolution numerical models are required for accurate simulation of the small scales of the haboob process, with high velocity surface winds produced by strong convection and severe downbursts. Dust productive areas in this region consist mainly of agricultural fields, with soil surfaces disturbed by plowing and tracks of land in the high Sonoran Desert …

Geog 140: Human Geography—A Peer Review Of Teaching Project Inquiry Portfolio, Katherine Nashleanas

UNL Faculty Course Portfolios

Large lecture classes, often of 100 students or more, present unique challenges to both teaching and learning. The common method of “delivery” by instructors is lecture, often augmented by a set of Power Point slides while the research literature shows that this more traditional way of teaching does not reach students in the way we hope and often assume. At the same time, most of the current students populating these classes are born of the Digital Age and have different expectations for learning, requiring new approaches in the classroom. Faculty are exhorted to incorporate more critical thinking in their classes …

Landscape And Impervious Surface Mapping In The Twin Cities Metropolitan Area Using Feature Recognition And Decision Tree Techniques, Philipp Nagel

All Graduate Theses, Dissertations, and Other Capstone Projects

Land Use and Land Cover (LULC) and Impervious Surface Area (ISA) are important parameters for many environmental studies, and serve as an essential tool for decision makers and stakeholders in Urban & Regional planning. Newly available high spatial resolution aerial ortho-imagery and LiDAR data, in combination with specialized, object-oriented and decision-tree classification techniques, allow for accurate mapping of these features. In this study, a method was developed to first classify LULC using an object-based classifier, and then use the resulting map as input for a decision-tree model to classify ISA in the Twin Cities Metropolitan Area in Minnesota. It was …

A Dynamic, Distributed Hydrologic Model For The Blue Earth River Watershed, Minnesota With Implications Regarding Land Use And Water Quality, Michael L. Merlini

All Graduate Theses, Dissertations, and Other Capstone Projects

The Blue Earth River (BER) watershed covers approximately one million acres of south-central Minnesota and northern Iowa. Modern farming practices have led to the loss of over 90 percent of the watershed's original wetlands. Corresponding changes in runoff and stream flow have led to dramatically reduced water quality in the BER's main stem following most precipitation events. The purpose of this research is to examine the relationships among precipitation, infiltration, base flow, and runoff in the Blue Earth River watershed basin.

This study developed a calibrated numerical hydrologic model for BER watershed using the distributed flow model, Vflo™. The model …

Birds And Beaches: The Affective Geographies And Sense Of Place Of Participants In The Coasst Citizen Science Program, Benjamin Kent Haywood

Theses and Dissertations

Participatory science research initiatives within the natural sciences like citizen science or crowd sourcing have enjoyed a recent explosion in popularity due to the efficient and expansive data collection processes they foster and the opportunities for general science outreach and education they provide. Now often the tool of choice among informal science outreach practitioners, Public Participation in Scientific Research (PPSR) programs are purported to expand knowledge and understanding of science and ecology, increase the relevancy of science for society, and cultivate more environmentally sustainable attitudes and behaviors. Despite such claims, the influence and impact of participatory science engagement is still …

Comparison Of Ground-To-Air Visibility Analysis Methods, Erica Pfister-Altschul

Theses and Dissertations

When a disaster occurs, remotely sensed imagery is critical for emergency responders. Aircraft collect digital images of damaged areas to assist with damage assessment and response planning. Such airborne imagery can be transmitted directly from the plane to ground antennae and internet-connected dispersal, allowing for faster acquisition of data. However, air-to-ground transmission of images requires near-constant visibility between the aircraft transmitter and ground station antenna. This research uses GIS-based models to identify the ground station locations that can reliably receive data from aircraft, using a variety of visibility analysis methods and a comparison of their performance. A custom algorithm is …

Justice And Immigrant Latino Recreation Geography In Cache Valley, Utah, Jodie Madsen, Claudia Radel, Joanna Endter-Wada

Environment and Society Faculty Publications

Latinos are the largest U.S. non-mainstreamed ethnic group, and social and environmental justice considerations dictate recreation professionals and researchers meet their recreation needs. This study reconceptualizes this diverse group’s recreation patterns, looking at where immigrant Latino individuals in Cache Valley, Utah do recreate rather than where they do not. Through qualitative interviews and interactive mapping, thirty participants discussed what recreation means to them and explained their recreation site choices. Findings suggest that recreation as an activity done outside the home, for fun with others, leads participants to seek spaces with certain characteristics. Reconceiving recreation more broadly and framing it from …

Spatial Analysis Of Human-Induced Vegetation Productivity Decline Over Eastern Africa Using A Decade (2001-2011) Of Medium Resolution Modis Time-Series Data, Tobias Landmann, Olena Dubovyk

All Peer-Reviewed Publications

Climate variation and land transformations related to exploitative land uses are among the main drivers of vegetation productivity decline and ongoing land degradation in East Africa. We combined analysis of vegetation trends and cumulative rain use efficiency differences (CRD), calculated from 250-m MODISNDVI time-series data, to map vegetation productivity loss over eastern Africa between 2001 and 2011.The CRD index values were furthermore used to discern areas of particular severe vegetation productivity loss over the observation period. Monthly 25-km Tropical Rainfall Measuring Mission (TRMM) datametrics were used to mask areas of rainfall declines not related to human-induced land productivity loss. To …

Values Mapping With Latino Forest Users: Contributing To The Dialogue On Multiple Land Use Conflict Management, Kelly Biedenweg, Lee Cerveny, Rebecca J. Mclain

Institute for Sustainable Solutions Publications and Presentations

Values mapping that represents how humans associate with natural environments is useful for several purposes, including recognizing and addressing different perceptions of natural resource ownership and management priorities, documenting traditional ecological knowledge, and spatially identifying the public's perception of economic and non-economic services provided by natural resources (McLain et al. 2013). The majority of this work has been conducted in developing countries and with disenfranchised communities, where participatory mapping associated with natural resource management is more widely practiced. As access to GIS technology has expanded, however, several projects have tested the benefits of values mapping for natural resource management decisions …

Recent Trends In Temperature And Relative Humidity In Bawku East, Northern Ghana, Kwasi Frimpong, Jacques D. Oosthuizen, Eddie J. Van Etten

Research outputs 2014 to 2021

Extensive analyses of trends in mean annual and mean seasonal minimum and maximum temperatures and relative humidity were examined for Bawku East, northern Ghana, for the period 1961 to 2012. Mean monthly maximum and minimum temperatures were used to analyse and establish recent temperature trends on an annual and seasonal basis. The year was divided into rainy and dry seasons for the seasonal trends. Mean monthly relative humidity at 6 am and 3 pm from 1961 to 2012 were considered to show recent trends in humidity since temperature and humidity interact to determine the heat exposure for outdoor workers. Regression …

Climate Analysis Using Tree-Rings From The Wind River Range, Wyoming, Derek Richards

Dissertations and Theses @ UNI

This study utilizes tree‐rings from the Wind River Range to determine past climates in this region of Wyoming and how they may have been affected by climate oscillations connected to the Pacific Ocean, such as El Nino-Southern Oscillation (ENSO) and Pacific Decadal Oscillation (PDO). The research considers what type(s) of past climatic cycles can be found in a roughly 500‐year series of tree‐rings collected from the Southeast Wind River Range using dendroclimatology and spectral analysis. It includes the reconstructed past temperature and precipitation data and how these compare with other reconstructions near the study area. The tree‐rings were found to …

Integrated Spatial Analysis Of Volunteered Geographic Information, Haydn Lawrence

Theses and Dissertations (Comprehensive)

Volunteered Geographic Information (VGI) is becoming a pervasive form of data within geographic academic research. VGI offers a relatively new form of data, one with both potential as a sensitive way to collect information about the world, and challenges associated with unknown and heterogeneous data quality. The lack of sampling control, variable expertise in data collection and handling, and limited control over data sources are significant research challenges. In this thesis, data quality of VGI is tackled as a general composite measure based on coverage of the dataset, the evenness in the density of data, and the relative evenness in …

Understanding The Long-Term Spatiotemporal Dynamics Of The Taimyr Reindeer Herd During The Summer Concentration Period, Matthew D. Cooney

Dissertations and Theses @ UNI

This study was part of a larger research effort devoted to investigation of spatiotemporal patterns and dynamics of the Taimyr Reindeer Herd (TRH) migration under changing climate and environmental conditions. The research aimed to systematize and analyze available historical (archival) data on wild reindeer (Rangifer tarandus L.) migration and ecosystems change in the Taimyr Peninsula, Russia. The summer concentration patterns of the TRH as observed from 1969-2009 were investigated through the utilization of existing and innovative spatioanalytic methods and advanced GIS technologies not previously used to examine R. tarandus migration in the Russian Arctic. The project applied and tested the …

Understanding The Impact Of Vegetation On Surface Roughness Length For Enhancing Wind Resource Characterization In Iowa, Andrei Vladimirovich Kushkin

Dissertations and Theses @ UNI

Wind energy development shows a rapid growth in the United States. This renewable energy source not only mitigates environmental concerns by reducing greenhouse gas emission, but also provides energy independence. Wind is clean and abundant, and is one of the most promising sources of alternative energy. Iowa is among the top wind energy producers in the nation, it is third by installed capacity and first in per capita production. In order to utilize wind resource potential most efficiently, accurate wind resource assessments are required. Changes in the aerodynamic characteristics of a site can have a major influence on the wind …

Developing An Integrated Spatially Explicit Scale Dependent Modeling Framework For Wind Farm Suitability Assessment In Iowa, Tesfay G. Russell

Dissertations and Theses @ UNI

Wind energy development is occurring rapidly in the United States due to the drive for energy independence and to mitigate environmental concerns. Wind is a clean, abundant, and entirely renewable source of energy and the most promising source of alternative energy. Among the top wind energy producers in the nation, the state of Iowa is experiencing tremendous growth and it’s projected to grow. However, despite the vast development, the contributing factors and spatial decision principles for optimal wind farms placement are not yet well understood. This research advanced an empirical methodology for building site suitability assessment framework for the state …

Self-Reliance Beyond Neoliberalism: Rethinking Autonomy At The Edges Of Empire, Karen Hébert, Diana Mincyte

Publications and Research

Across scholarly and popular accounts, self-reliance is often interpreted as either the embodiment of individual entrepreneurialism, as celebrated by neoliberal designs, or the basis for communitarian localism, increasingly imagined as central to environmental and social sustainability. In both cases, self-reliance is framed as an antidote to the failures of larger state institutions or market economies. This paper offers a different framework for understanding self-reliance by linking insights drawn from agrarian studies to current debates on alternative economies. Through an examination of the social worlds of semisubsistence producers in peripheral zones in the Global North, we show how everyday forms of …

Bastard Immigrants: Asylum Seekers Who Arrive By Boat And The Illegitimate Fear Of The Other, Lelia R. Green, Anne Aly

Research outputs 2014 to 2021

The human capacity to marginalise and discriminate against others on the basis of innate and constructed characteristics is evident from the long history of discrimination against people whose existence is ‘illegitimate’, defined as being outside the law. What is inside or outside the law depends upon the context under consideration. For example, in societies such as ancient Greece and the antebellum United States, where slavery was legal, people who were constructed as ‘slaves’ could legitimately be treated very differently from ‘citizens’: free people who benefit from a range of human rights (Northup). The discernment of what is legitimate from that …

Dynamic Modeling Of Gnss Troposphere Wet Delay For Estimation Of Precipitable Water Vapour, Ahmed El-Mowafy, Johnny Lo

Research outputs 2014 to 2021

Proper dynamic modelling of the troposphere wet delay using the Global Navigation Satellite Systems (GNSS) measurements is important in precise point positioning and in estimation of the PrecipitableWater Vapour (PWV) for weather forecast. The random walk (RW) and the first-order Gauss-Markov (GM) autocorrelation models are commonly used for this purpose. However, it was found that these models consistently underestimate the temporal correlations that exist among the troposphere wet delay. Therefore, a new dynamic model is proposed. The performance of the proposed model in following the autocorrelation of actual data is demonstrated and its impact on the near-real time estimation of …

Creative Heartland: Creative Capital And Knowledge Economy In Micropolitan Midwest, Philip A. Cavin

Dissertations and Theses @ UNI

Recent regional development studies increasingly focus on creative economies that provide an alternative perspective to regional development in a globalizing world-economy. However, most research in economic geography of creativity and innovation is exclusively concerned with larger metropolitan areas. The lack of attention does not make knowledge-based economy less relevant or creative capital less important in smaller urban regions, where it acts as an agent of economic development and revitalization. This study is the first attempt to use creative capital metrics and a combination of qualitative and qualitative analyses to investigate the creative capital and its economic implications in micropolitan areas …

Crater Detection Via Genetic Search Methods To Reduce Image Features, Joseph Paul Cohen

Graduate Masters Theses

Recent approaches to crater detection have been inspired by face detection's use of gray-scale texture features. Using gray-scale texture features for supervised machine learning crater detection algorithms provides better classification of craters in planetary images than previous methods. When using Haar features it is typical to generate thousands of numerical values from each candidate crater image. This magnitude of image features to extract and consider can spell disaster when the application is an entire planetary surface. One solution is to reduce the number of features extracted and considered in order to increase accuracy as well as speed. Feature subset selection …