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1
Ault, Toby R. "THE CONTINUUM OF DROUGHT IN WESTERN NORTH AMERICA." Diss., The University of Arizona, 2011. http://hdl.handle.net/10150/204333.
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The continuum of western North American hydroclimate during the last millennium is analyzed here using instrumental records, proxy data, and global climate model (GCM) simulations. We find that variance at long timescales (low frequencies) is generally more substantial than variance at short timescales (high frequencies). We find that local sources of autocorrelation (e.g., soil moisture storage) likely explain the tendency for variance to increase from monthly to interannual timescales, but that variance at longer timescales requires remote climate sources of variability. Our analysis of global climate model data indicates that at least one fully coupled GCM can reproduce the characteristics of the continuum on short (interannual) and long (multicentury) timescales, but that proxy spectra and GCM spectra disagree about the amount of variance present on intermediate (decadal to centennial) timescales. Since instrumental records, as well as multiple independent types of paleoclimate records, provide evidence that variance increases with timescale at these frequencies, and because numerical experiments indicate that local autocorrelation is not a likely source of variance at these timescales, we argue that climate model simulations underestimate the full range of low-frequency drought variability. Moreover, the models may also underestimate the risk of future megadroughts, which we attempt to quantify using a new method that combines frequency information from observational data with projections of 21st century hydroclimate. Our results indicate that the risk of a severe, decadal-scale drought during the coming century is at least 1-in-10 for most of the US Southwest, and may be as high as 1-in-3. These findings should be incorporated into adaptation and mitigation strategies to cope with regional climate variability and climate change.
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Miller, Becky Akiko. "The Phylogeography of Prosopium in Western North America." BYU ScholarsArchive, 2006. https://scholarsarchive.byu.edu/etd/1002.
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The mountain whitefish (Prosopium williamsoni) has been largely overlooked in population genetic analyses despite its wide distribution in discrete drainage basins in western North America for over four million years. Its closest sister taxa the Bear Lake whitefish (P. abyssicola), Bonneville cisco (P. gemmifer), and Bonneville whitefish (P. spilonotus) are found only in Bear Lake Idaho-Utah and were also included in the analyses. A total of 1,334 cytochrome b and 1,371 NADH dehydrogenase subunit 2 sequences from the Bonneville Basin, the Columbia River Sub-basin, the lower Snake River Sub-basin, the upper Snake River Sub-basin, the Green River Basin, the Lahontan Basin, and the Missouri Basin were examined to test for geographically based genetic differentiation between drainage basins and sub-basins and phylogeographic relationships to determine the invasion route of Prosopium into western North America and to aid in understanding current relationships. Prosopium entered the region via the Missouri River connection to Hudson Bay and moved in two waves: one colonized the lower Snake River Sub-basin, Columbia River Sub-basin, and the Lahontan Basin; the second wave colonized the upper Snake River Sub-basin, Bonneville Basin, Green River Basin, and established the Bear Lake Prosopium. Mountain whitefish exhibit a large amount of geographical genetic differentiation based on drainage basin except between the upper Snake River and the Bonneville Basin while the Bear Lake Prosopium show large amounts of gene flow between the three species. The apparent paraphyly of the mountain whitefish and the limited genetic structure of the Bear Lake Prosopium warrant recognition in the management of Prosopium and raise questions regarding species definitions in the group.
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Caruthers, Andrew Harry. "Pliensbachian–Toarcian (Early Jurassic) extinction in western North America." Thesis, University of British Columbia, 2013. http://hdl.handle.net/2429/44233.
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The Pliensbachian–Toarcian marine extinction is observable at the species and generic levels. Ammonite diversity data from Europe and parts of the Arctic suggest a multi-phased event with diversity declining over six separate intervals. The main-phase of decline begins at the Pliensbachian–Toarcian boundary and extends into the Early Toarcian to a level correlative with the Tenuicostatum / Serpentinum Zone boundary. To date only this main-phase has been demonstrated as being global in extent, affecting multiple taxonomic groups. The entire Pliensbachian-Toarcian extinction has been attributed to regional and global controlling mechanisms associated with the Volcanic Greenhouse Scenario, an hypothesis linking eruption of the Karoo–Ferrar large igneous province (LIP) to global warming and mass extinction, specifically involving the release of methane hydrate from shelf reservoirs and a global marine anoxic event in the Early Toarcian (the T–OAE).
The study presented herein uses paleontology and isotope geochemistry to investigate the duration and potential controlling mechanisms of this protracted extinction. A primary objective is to compare new data from western North America with previously established records in Europe, testing: 1) the multi-phased nature of this extinction, 2) its magnitude within two taxonomic groups (ammonoids and foraminifera) in western North America and 3) its controlling mechanisms, relating to methane hydrate release and geographic extent of the T-OAE.
Results show that all six phases of species decline are recognizable in western North America, even the oldest episode which was previously thought to be an event restricted to the Tethys Ocean area of Europe. This research strongly supports a correlation between the timing of the entire multi-phased extinction and formation of the Karoo igneous province. The study also provides one of the first records of the Early Toarcian ‘negative carbon-isotope excursion’ outside the Tethys Ocean area (concomitant with the main-phase of extinction) which implicates global methane hydrate release. Lastly, geochemical results do not support the presence of an anoxic water mass in the northeast paleo Pacific Ocean at the time of the so-called global Toarcian event (T-OAE).
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Povey, David A. R. "Palaeobotanical determination of Tertiary palaeoelevation in western North America." Thesis, University of Oxford, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307942.
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Booth, Evan L. J. "Modeling the effects of climate change on glaciers in the Upper North Saskatchewan River Basin." Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Geography, c2011, 2011. http://hdl.handle.net/10133/3227.
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This thesis is focused on determining the rate at which the climate of
western North America (WNA) has changed in recent history, and looks at the
impact that projected future climatic changes will have on a large glaciated
watershed in the Canadian Rocky Mountains. The rate of change over WNA is
quantified for 485 climate stations for the period 1950-2005 using indicators
developed by the World Meteorological Organization (WMO). Results of the
analysis show statistically significant historical trends across the study area. To
gauge the effect of climate change on glaciers, a mass balance model was
developed and integrated with the University of Lethbridge GENESYS
hydrometeorological model. GCM future climate scenarios were used to model
change in the Upper North Saskatchewan River Basin through 2100. Results
forecast dramatic declines (> 80%) in total glacier area, ice volume, and
streamflow contribution by 2100.<br>ix, 137 leaves ; 29 cm
6
Lapp, Suzan L., and University of Lethbridge Faculty of Arts and Science. "Climate warming impacts on alpine snowpacks in western North America." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2002, 2002. http://hdl.handle.net/10133/186.
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A wide area assessment of forecast changes in wintertime synoptic conditions over western North America is combined with a meso-scale alpine hydrometeorology model to evaluate the joint impact(s) of forecast climate change on snowpack conditions in an alpine watershed in the southern Canadian Rockies. The synoptic analysis was used to generate long-term climate time series scenarios using the CCCma CGCM1. An alpine hydrometerology model is used to predict changes in wintertime precipitation at the watershed scale. A mass balance snow model is utilized to predict the overall snow accumulation throughout a watershed. A vapour transfer model has been incorporated in the snow model to estimate snow volumes more accurately. The synoptic analysis and GCM output forecasts a modest increase in both winter precipitation and temperatures in the study area, resulting in a decline of winter snow accumulations, and hence an expected decline in spring runoff.<br>ix, 87 leaves : ill. ; 28 cm.
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McKechnie, Nicole R., and University of Lethbridge Faculty of Arts and Science. "Predicting climate change impacts on precipitation for western North America." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, 2005, 2005. http://hdl.handle.net/10133/269.
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Global Circulation Models (GCMs) are used to create projections of possible future climate characteristics under global climate change scenarios. Future local and regional precipitation scenarios can be developed by downscaling synoptic CGM data. Daily 500-mb geopotential heights from the Canadian Centre for Climate Modeling and Analysis's CGCM2 are used to represent future (2020-2050) synoptics and are compared to daily historical (1960-1990) 500-mb geopotential height reanalysis data. The comparisons are made based on manually classified synoptic patterns identified by Changnon et al. (1993.Mon. Weather Rev. 121:633-647). Multiple linear regression models are used to link the historical synoptic pattern frequencies and precipitation amounts for 372 weather stations across western North America,. The station-specific models are then used to forecast future precipitation amounts per weather station based on synoptic pattern frequencies forecast by the CGCM2 climate change forcing scenario. Spatial and temporal variations in precipitation are explored to determine monthly, seasonal and annual trends in climate change impacts on precipitation in western North America. The resulting precipitation scenarios demonstrate a decrease in precipitation from 10 to 30% on an annual basis for much of the south and western regions of the study area. Seasonal forecasts show variations of the same regions with decreases in precipitation and select regions with increases in future precipitation. A major advancement of this analysis was the application of synoptic pattern downscaling to summer precipitation scenarios for western North America.<br>ix, 209 leaves : col. maps ; 29 cm.
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Eshleman, Jason Aaron. "Mitochondrial DNA and prehistoric population movements in western North America /." For electronic version search Digital dissertations database. Restricted to UC campuses. Access is free to UC campus dissertations, 2002. http://uclibs.org/PID/11984.
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Coats, S., J. E. Smerdon, B. I. Cook, R. Seager, E. R. Cook, and K. J. Anchukaitis. "Internal ocean-atmosphere variability drives megadroughts in Western North America." AMER GEOPHYSICAL UNION, 2016. http://hdl.handle.net/10150/621966.
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Multidecadal droughts that occurred during the Medieval Climate Anomaly represent an important target for validating the ability of climate models to adequately characterize drought risk over the near-term future. A prominent hypothesis is that these megadroughts were driven by a centuries-long radiatively forced shift in the mean state of the tropical Pacific Ocean. Here we use a novel combination of spatiotemporal tree ring reconstructions of Northern Hemisphere hydroclimate to infer the atmosphere-ocean dynamics that coincide with megadroughts over the American West and find that these features are consistently associated with 10-30 year periods of frequent cold El Nino-Southern Oscillation conditions and not a centuries-long shift in the mean of the tropical Pacific Ocean. These results suggest an important role for internal variability in driving past megadroughts. State-of-the-art climate models from the Coupled Model Intercomparison Project Phase 5, however, do not simulate a consistent association between megadroughts and internal variability of the tropical Pacific Ocean, with implications for our confidence in megadrought risk projections.
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Hrubeniuk, Jewel N. "Natural regeneration of white spruce in western North America with specific reference to Western Canada." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape17/PQDD_0024/MQ32136.pdf.
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Shao, Xuemei. "Statistical relationships between tree growth and climate in western North America." Diss., The University of Arizona, 1992. http://hdl.handle.net/10150/185825.
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The objective of this study is to examine large-scale spatial patterns of tree growth and climatic variation and to investigate the possible role of climate in determining tree growth patterns over space. This study represents one of the first uses of geostatistical methods to extract information about the spatial variation of climate from tree rings in western North America. It is also one of the first uses of data in spatial series to study the relationships of spatial variations between climate and tree growth. Geostatistics analyzes the spatial structure of the variables by assuming that adjoining data are correlated with each other over space and that the particular relationship expressing the extent of spatial correlation can be analytically and statistically captured in a function. It is applied to both June Palmer Drought Severity Index (PDSI) and ring-width index data from western North America. One basic assumption of applying geostatistics in this study is that the spatially uncorrelated small-scale variations are insignificant and represent background noise in large-scale dendroclimatic studies. The statistical relationships between the spatial variations of June PDSI and ring-width index are studied by simple scatter diagrams and correlation analysis. This is done in terms of yearly variations and variations of spatial patterns. Both of them support the contention that the large-scale spatial variations in ring-width index data can be used to infer the spatial variations of climate variables. Based upon the results of this research it can be concluded that geostatistics is a viable method to characterize the spatially correlated variations in dendroclimatology. By applying geostatistics to data sets, information about the spatial variations of climate contained in tree-ring data are enhanced, and the large-scale variations of climate are emphasized. The analysis of yearly relationships over space is particularly useful for identifying statistical relationships between climate and tree growth in a geographic region. The main factors of climate controlling ring-width index are identified as well as the less frequent limiting events. Once the statistical relationships are validated, they can be used to infer the spatial variations of past climate from variations in tree-ring index.
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Hemphill-Haley, Mark Allen. "Multi-scaled analyses of contemporary crustal deformation of western North America /." view abstract or download file of text, 1999. http://wwwlib.umi.com/cr/uoregon/fullcit?p9948021.
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Thesis (Ph. D.)--University of Oregon, 1999.<br>Typescript. Includes vita and abstract. Includes bibliographical references (leaves 225-237). Also available for download via the World Wide Web; free to University of Oregon users. Address: http://wwwlib.umi.com/cr/uoregon/fullcit?p9948021.
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Witgen, Michael J. "An infinity of nations : how Indians, empires, and western migration shaped national identity in North America /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/10402.
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Chandler, John L. "Hydrologic Change in Western North America: Regional Impacts and the Role of Climate." Fogler Library, University of Maine, 2008. http://www.library.umaine.edu/theses/pdf/ChandlerJL2008.pdf.
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Codling, James. "Presbyterian missions to Indians in western Canada." Theological Research Exchange Network (TREN), 1990. http://www.tren.com.
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Gorman, Andrew Robert. "Deep Probe, investigating the lithosphere of western North America with refraction seismology." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/NQ61096.pdf.
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Serefiddin, Feride Schwarcz H. P. "Paleoclimate models for western North America as inferred from speleothem isotope records /." *McMaster only, 2003.
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Thrasher, Bridget L. "Regional climate modeling studies of western North America under early Eocene conditions /." Diss., Digital Dissertations Database. Restricted to UC campuses, 2009. http://uclibs.org/PID/11984.
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Hill, Matthew E. "Causes of Regional and Temporal Variation in Paleoindian Diet in Western North America." Diss., The University of Arizona, 2007. http://hdl.handle.net/10150/196065.
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This dissertation explores geographic and diachronic variation in Great Plains and Rocky Mountain Paleoindian (12,500-7000 14C years before present) forager exploitation of animal resources in order to explore how use of different habitats influenced land-use and subsistence strategies. To accomplish this goal, this study documented the full range of variability in the Paleoindian record using a combination of published data and new data. These patterns were then compared to explicit predictions derived from behavioral ecology and animal ethology and biology studies. The results, presented in this dissertation, allow the testing of several, often contradictory, important subsistence-settlement hypotheses in current Paleoindian research, specifically the ongoing debate about Paleoindian diet breadth and human causes of megafaunal extinction. Overall, there appears to be a covariance between environmental zone and forager land use. Paleoindian foragers structured their land use according to the presence and nature of a number of important resources within major environmental zones. Specifically, this study finds sites in grassland settings with low diversity of resources have lower artifact densities and are often dominated by exotic lithic raw materials. In these same areas prehistoric groups made almost exclusive use of large fauna. Sites in foothill/mountain or alluvial valley settings with ecologically high density and high diversity have higher proportions of short-term camps than do other areas and those camps have higher artifact density than do other types of sites. These sites exhibit a mixed use of small- and medium-sized game. Overall this study shows Paleoindian hunters had only modest impact on prey species.
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Neff, Kirstin Lynn. "Seasonality of Groundwater Recharge in the Basin and Range Province, Western North America." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556969.
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Alluvial groundwater systems are an important source of water for communities and biodiverse riparian corridors throughout the arid and semi-arid Basin and Range Geological Province of western North America. These aquifers and their attendant desert streams have been depleted to support a growing population, while projected climate change could lead to more extreme episodes of drought and precipitation in the future. The only source of replenishment to these aquifers is recharge. This dissertation builds upon previous work to characterize and quantify recharge in arid and semi-arid basins by characterizing the intra-annual seasonality of recharge across the Basin and Range Province, and considering how climate change might impact recharge seasonality and volume, as well as fragile riparian corridors that depend on these hydrologic processes. First, the seasonality of recharge in a basin in the sparsely-studied southern extent of the Basin and Range Province is determined using stable water isotopes of seasonal precipitation and groundwater, and geochemical signatures of groundwater and surface water. In northwestern Mexico in the southern reaches of the Basin and Range, recharge is dominated by winter precipitation (69% ± 42%) and occurs primarily in the uplands. Second, isotopically-based estimates of seasonal recharge fractions in basins across the region are compared to identify patterns in recharge seasonality, and used to evaluate a simple water budget-based model for estimating recharge seasonality, the normalized seasonal wetness index (NSWI). Winter precipitation makes up the majority of annual recharge throughout the region, and North American Monsoon (NAM) precipitation has a disproportionately weak impact on recharge. The NSWI does well in estimating recharge seasonality for basins in the northern Basin and Range, but less so in basins that experience NAM precipitation. Third, the seasonal variation in riparian and non-riparian vegetation greenness, represented by the normalized difference vegetation index (NDVI), is characterized in several of the study basins and climatic and hydrologic controls are identified. Temperature was the most significant driver of vegetation greenness, but precipitation and recharge seasonality played a significant role in some basins at some elevations. Major contributions of this work include a better understanding of recharge in a monsoon-dominated basin, the characterization of recharge seasonality at a regional scale, evaluation of an estimation method for recharge seasonality, and an interpretation of the interaction of seasonal hydrologic processes, vegetation dynamics, and climate change.
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Patel, Sameer Yogesh. "Characterising carbon cycle perturbations in the Cenomanian western interior seaway of North America." Thesis, University of Southampton, 2017. https://eprints.soton.ac.uk/416888/.
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As current global temperatures continue to rise at an accelerated pace, it is becoming increasingly important to examine how the planet has responded to previous periods of global warming in order to gain valuable insights into how the Earth system may react in the future. The mid-Cretaceous (~101-91 Ma) provides an excellent case study of a prolonged greenhouse climatic state, where high rates of oceanic crust production and enhanced large igneous province-related volcanism released vast quantities of greenhouse gases into the atmosphere. Consequently, global temperatures reached their highest level for the past 450 Myr during the Cenomanian to Turonian stages, and peak sea levels led to the development of epeiric seas such as the Western Interior Seaway (WIS), which extended southwards from the northern Boreal Ocean, across central North America, and into the Tethys Ocean. Superimposed upon this greenhouse climate were a series of even more extreme climate perturbations, of which Oceanic Anoxic Event 2 (OAE 2), spanning the Cenomanian-Turonian boundary (94.1 Ma), was the most prominent, globally widespread, extreme climatic event of the Late Cretaceous. OAE 2 represents a major global carbon cycle perturbation, during which enhanced marine productivity coupled with the expansion of oxygen minimum zones across global oceans led to the extensive deposition of organic-rich black shale deposits. An earlier Mid-Cenomanian Event (MCE I; ~96.5 Ma) is taken to be a precursor to OAE 2, as it marks the beginning of a ~2 Myr oceanographic reorganisation during which bottom waters started to become increasingly oxygen-depleted. MCE I is identified on a global scale by a distinct dual-peaked positive carbon isotope excursion. However, with little evidence of widespread organic-rich mudrock deposition, most studies of MCE I are from carbonate-rich successions, thus limiting the range of analyses that can be undertaken. Here, a high-resolution, integrated organic and inorganic multi-proxy study of the Rebecca K Bounds-1 core from western Kansas has been undertaken in order to elucidate environmental and oceanographic changes during MCE I and the interval leading up to OAE 2 in the central-eastern WIS. MCE I is identified in an organic-rich sequence through a dual-peaked, positive organic carbon isotope excursion (MCE 1a and MCE 1b, respectively), and is determined to coincide with the establishment of a fully connected seaway that extended from the northern Boreal Ocean to the Tethyan Ocean in the south via the WIS in the mid-Cenomanian, as evidenced by diversified palynological, foraminiferal, and geochemical changes between MCE 1a and MCE 1b. Periodically enhanced planktic productivity is linked to ~50 kyr obliquity cycles across MCE I through cyclostratigraphic analysis. This heightened productivity is attributed to the strengthening of meridional winds during obliquity maxima, which may have increased upwelling-related nutrient input into Tethyan surface waters in equatorial regions. Palynological, redox-sensitive trace metal, lipid biomarker, and sedimentological data reveal that a complex dynamic oceanographic system prevailed in the central region of the WIS, with mixed early Cenomanian Tethyan-Boreal waters eventually being replaced by a northward migrating Tethyan water mass in the mid- to late Cenomanian. This situation prevailed until OAE 2 set in, when a rapid southward incursion of Boreal waters extended as far as the southern margin of the seaway. This multi-faceted study provides a new in-depth, high-resolution example of how Earth systems and environmental conditions reacted to periods of stressed, greenhouse climatic conditions.
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Whaley, Gray H. "Creating Oregon from Illahee : race, settler-colonialism, and native sovereignty in Western Oregon, 1792-1856 /." view abstract or download file of text, 2002. http://wwwlib.umi.com/cr/uoregon/fullcit?p3055720.
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Thesis (Ph. D.)--University of Oregon, 2002.<br>Typescript. Includes vita and abstract. Includes bibliographical references (leaves 404-428). Also available for download via the World Wide Web; free to University of Oregon users.
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Page, David. "Fine-grained volcanic toolstone sources and early use in the Bonneville Basin of western Utah and eastern Nevada /." abstract and full text PDF (UNR users only), 2008. http://0-gateway.proquest.com.innopac.library.unr.edu/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:1455650.
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Thesis (M.A.)--University of Nevada, Reno, 2008.<br>"May 2008." Includes bibliographical references (leaves 146-158). Library also has microfilm. Ann Arbor, Mich. : ProQuest Information and Learning Company, [2009]. 1 microfilm reel ; 35 mm. Online version available on the World Wide Web.
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Roberge, Alain. "Analysis of intense sub-tropical moisture transports into high latitudes of western North America." Thesis, McGill University, 2008. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=19280.
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There can often be significant interactions between high and tropical latitudes during the Northern Hemisphere's cold season. In periods of amplified atmospheric flow, these interactions can lead to the poleward transport of significant tropical moisture from near Hawaii into northwestern North America. These are pineapple express (PE) events. This study documents the synoptic-scale signatures associated with the PE. A trajectory analysis was used to partition the events into three different synoptic types according to the origin of their trajectories. Results indicate that this large scale moisture transport is often associated with the sub-tropical jet stream, which is curved due to a high pressure ridge concomitant with the Aleutian Low. Additionally, similar moisture transport may be observed in absence of the ridge with a stronger Aleutian Low. Furthermore, thickness anomalies after the events revealed a significant warming over North America lasting for at least three days.<br>Il peut souvent y avoir des interactions importantes entre les latitudes nordiques et tropicales durant l'hiver de l'hémisphère nord. Durant des périodes de courant atmosphérique amplifié, ces interactions peuvent mener à un transport important d'humidité tropicale de la région d'Hawaii jusqu'au au nord-ouest de l'Amérique du Nord. Ces évènements se nomment « pineapple expresses » (PE). Cette étude documente les caractéristiques synoptiques de ces évènements. Une analyse de trajectoires a été utilisée pour diviser les évènements en trois différents types synoptiques selon l'origine de leurs trajectoires. Les résultats indiquent que ce transport d'humidité à grande échelle est souvent associé avec le courant jet subtropical, qui se courbe due à une crête de haute pression accompagnée du système de basse pression des Aléoutiennes. De plus, un transport d'humidité aussi important peut être observé sans la présence de cette crête de haute pression mais avec un plus fort système de basse pression des Aléoutiennes. Parallèlement, les anomalies d'épaisseurs de l'atmosphère après ces évènements du PE révèlent un réchauffement significatif en Amérique du Nord pendant au moins trois jours.
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Gardner, James Douglas. "Systematics of albanerpetontids and other lissamphibians from the Late Cretaceous of western North America." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ59589.pdf.
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Salo, Lucinda. "Ecology and biogeography of red brome (Bromus madritensis subspecies rubens) in western North America." Diss., The University of Arizona, 2002. http://hdl.handle.net/10150/279993.
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Red brome [Bromus madritensis subsp. rubens (L.) Husn.] arrived in western North America before 1880 and has since invaded even relatively undisturbed areas. Populations of this annual grass, native to the Mediterranean Basin, fluctuate widely in response to variations in winter precipitation and can produce large amounts of persistent fine fuels. The biogeography portion of this research describes the arrival, spread, and current extent of red brome in western North America and estimates the potential climatic range of this grass in the USA. The ecology portion of this research investigates interactions between native Sonoran Desert winter annuals and four densities of red brome, from the equivalent of 300 to 1200 plants m⁻², at low (3) and high (540 μg NO₃ - g soil⁻¹) levels of soil nitrogen (N), to evaluate the relative intensity of interactions at low and high fertility. This study found no evidence of red brome occurrence in North America prior to 1879. This grass may have arrived with immigrants or agricultural products after the start of the California Gold Rush in 1848, perhaps in crop seed or in the fleece of sheep. Red brome appears best adapted to areas with minimum January temperatures between -5.4 and 3.9°C and total winter precipitation between 9.0 and 76.4 cm. However, the myriad factors mediating interactions among red brome, other species, and local environments in these areas will determine if this grass becomes established in any of these regions. This study found no evidence of reduced richness or diversity of Sonoran Desert annuals occurring with red brome. Red brome did not exclude species from this study, as neither emergence nor survival of native species were affected by this grass. However, red brome significantly interfered with growth of native species. Declines in total biomass of each of 11 analyzed species growing with red brome averaged 58.4% of biomass produced when this grass was not present. The intensity of interactions between red brome and Sonoran Desert annuals rarely varied with soil fertility and differences in growth of red brome and of native annuals between low and high N were similar.
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Fraser, K. J. "Petrogenesis of kimberlites from South Africa and lamproites from Western Australia and North America." Thesis, Open University, 1987. http://oro.open.ac.uk/54611/.
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Group 2 kimberlites from South Africa, and lamproites from Western Australia and North America are relatively unfractionated mantle-derived igneous rocks, situated on or close to ancient cratonic areas. They are characterised by high trace element contents, while the range in N d and Sr isotopes encompasses much of that reported for various upper and lower crustal rocks. It is argued that these features are not due to crustal contamination during magma ascent, rather they are source and extraction phenomena. The mantle source regions of these rocks were ancient (~ 1.0 to 2.5 Ga) and variably trace element enriched. Preservation of such regions within the mantle is most probable in the relatively 'cold' and 'rigid' subcontinental mantle lithosphere, which is believed to have been isolated from the convecting asthenosphere for a long time. The source regions of the kimberlites and lamproites were situated at various depths within the subcontinental mantle lithosphere, from within the amphibole stability field « 100 km) to within the diamond stability field (> 150 km). Low degrees of partial melting « 1 %), together with volatile composition and depth of melting, have significantly influenced the composition of the resultant kimberlite and lamproite magmas. Those magmas that originated from within the diamond stability field contain abundant entrained and dis aggregated mantle peridotite. This feature is related to melt migration and rapid ascent to the surface, from these mantle depths. The Sr, Nd and Pb isotope data record evidence of variable, but related trace element enrichment styles. The origin of these trace elements is either from recycled continental crust (e.g. pelagic sediment), or from intra-mantle processes (e.g. the migration and crystallisation of small volume silicate melts with variable volatile compositions). The available data are insufficient to determine between the models and further work in this area is required.
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Tuinstra, Annejet. "Post-Wildfire Debris Flows: Mapping and Analysis of Risk Factors in Western North America." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-446352.
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Climate change is leading to in an increase in frequency and severity of wildfires, which in turn can result in the formation of runoff-initiated post-wildfire debris flows. This type of debris flows is, like most debris flows, triggered by heavy precipitation events. Debris flows have the potential to cause much damage, and therefore it is important to analyse when and where the risk of these flows exists. This study aims to identify shared characteristics of basins that experienced post-wildfire debris flows in order to improve future risk analyses regarding such flows. These characteristics were studied through the analysis of 42 basins in 10 burned areas across western North America, which experienced a total of 67 post-wildfire debris flows between 2000 and 2018. Literature research and existing databases revealed the bedrock, soil texture and the timing of the flows compared to the wildfires. Spatial analysis using ArcMap allowed for the analysis of the burn severity of the basins, the hypsometry of the basins, and the mean slope of the basins. Analysis of these characteristics revealed the importance of the hypsometric integral, the soil texture, and the mean slope angle of the basins. In general, the hypsometric integral tends to fall between 0.50 and 0.60 and only soils with a coarse texture were identified for the basins. The mean slope angle of the basins is commonly between 25-30o, with a wider range of slopes being able to generate debris flows shortly after the fire. If multiple basins in a small area are burned, those with steeper slope angles have a higher potential to generate debris flows, while basins with steeper slopes do not have a higher risk on large regional scales. In order to generate post-wildfire debris flows the basin also needs to be burned at a large extent at low to medium severity, resulting in an extensive and strong water-repellent layer required to generate the runoff that is needed to generate a debris flow. Seasonal wetting during winters and drying of the soil during summers can reduce or enhance runoff respectively as well. As a result, post-wildfire debris flows occur mostly during the late summer months shortly after a wildfire when precipitation is increasing through summer storms, or a year later when the soil is dried and primed during the summer followed by such a summer storm. Fires during winter and thus outside the traditional wildfire season can lead to post-wildfire debris flows during winter as well due to the strength of the fresh water-repellent layer. Climate change which will lead to more fires during late autumn and winter months can thereby result in post-wildfire debris flows during winter, rather than only during the summer months following wildfires in the traditional fire season.<br>Jordskred uppstår när en sammanhängande jordmassa kommer i snabb rörelse. Det är en typ av naturolyckor som kan skada både infrastruktur och människor. Sannolikheten att ett jordskred inträffar ökar efter skogsbränder. Samtidigt kan klimatförändringar leda till en ökning av skogsbränder vilket i sin tur kan leda till en ökad risk för jordskred i framtiden. Syftet med det här projektet är att bidra till bedömningen av risken av jordskred till följd av skogsbänder i västra Nordamerika och att identifiera andra områden som också har en stor risk att drabbs av skred efter skogsbränder genom att identifiera riskfaktorer. Under projektets gång skapades en databas med områden där jordskred inträffade efter skogsbränder i västra Nordamerika. Den vetenskapliga litteraturen visade några egenskaper av skred och områdena, t.ex. när branden och skredet hände, vilken berggrund finns i området och texturen av jordarten i området. Dessutom användandes GIS (Geographical Information System) med satellitbilder och DEM (Digital Elevation models), som visade information om brandskador samt de geomorfologiska karaktärerna av områden. Resultaten visade att formationen av jordskred kräver omfattande låga till måttliga brandskador som resulterar i ett starkt vattenavvisande jordlager. Detta jordlager minskar infiltrationskapaciteten av jorden och resulterar i mer ytavrinning vilket orsakar skred till följd av brand. Även en grov textur av jordlagret är viktig eftersom den också bidrar till ett starkt vattenavvisande jordlager. Dessutom kan askpartiklar bli fångade in i stora porer i jord med en grov textur vilket minskar infiltrationskapaciteten och ökar ytavrinningen. Det finns alltså två krav för att ett jordskred ska inträffa efter en skogsbrand: i) omfattande låga-måttliga brandskador, och ii) en grov textur av jorden. Vidare finns det några ytterligare egenskaper som ökar risken för skred efter skogsbränder om de två kraven är uppfyllda. Den hypsometriska integralen (ett sätt att uttrycka hypsometrin av en dal) ligger oftast mellan 0.50-0.60 vilket är normal för en geomorfologiskt sett mogna område. Dessutom hade de flesta områdena i projektet en medellutning mellan 25o och 30o. Dock fanns det även tillfällen där värdena låg utanför dessa intervaller. Därför kan dessa värden i sig inte användas som riskfaktorer, utan borde de även kombineras med de övriga egenskaperna som beskrivs i den här undersökningen. Det är också relevant att veta när jordskred inträffar till följd av skogsbränder. Resultaten visade att skred kan hända strax efter skogsbränder i slutet av sommaren när det finns kraftigt regn. Det är då som det vattenavvisande jordlagret är som starkast. Det vattenavvisande lagret minskar i styrkan under året, men det är också möjligt att det inträffar ett jordskred under sommaren året efter en skogsbrand. Då är jorden torr i slutet av sommaren när kraftigt regn inträffar efter torra månader. Torr jorden bidrar även till en minskad infiltrationskapacitet. Regn i vinter gör jorden blöt vilket ökar infiltrationskapaciteten av jorden. Dessutom sker det även skogsbränder utanför den traditionella skogsbrandsäsongen nuförtiden, t.ex. tidigt i vintern. I så fall kan jordskred också inträffa under samma vinter strax efter skogsbranden, därför att det vattenavvisande jordlagret som skapas i branden fortfarande är starkt då. Som nämnts tidigare finns det en riskprofil som kan användas för att identifiera områden som har en hög risk för jordskred efter skogsbränder, men möjligheten att ett jordskred inträffar under vintern istället för (slutet av) sommaren bör även iakttas. Risken växer nämligen i samband med klimatförändringar som leder till mer skogsbränder; inte bara under sommaren, utan även under vintern.
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Wolsey, Des Jarlais Cheryl L. "Cultural characteristics of western educational structures and their effects on local ways of knowing." Diss., [Missoula, Mont.] : The University of Montana, 2009. http://etd.lib.umt.edu/theses/available/etd-10152009-141854.
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Cotton, Lacy Noel Ferdon Douglas Robert. "American Indian stereotypes in early western literature and the lasting influence on American culture." Waco, Tex. : Baylor University, 2008. http://hdl.handle.net/2104/5247.
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Kristiansen, Evan B. "Phylogeography of a highly variable butterfliy species in Western North America: Speyeria callippe (Lepidoptera: Nymphalidae)." Scholarly Commons, 2014. https://scholarlycommons.pacific.edu/uop_etds/183.
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Traditionally, methods for phylogenetic and phylogeographic inference have relied heavily on morphological data. Molecular data can provide an independent assessment of patterns and are particularly desirable when morphology may be under natural selection. Herein we present a phylogeographic analysis of the highly polytypic butterfly, Speyeria callippe. Samples were drawn from 71 populations across western North America. Phylogeographic trends are inferred from analysis of the gene Cytochrome oxidase subunit I ( CoI ). Patterns of mtDNA diversity imply historical panmixia and Mid-to-late Pliocene divergence from other Speyeria approximately xx mya. Diversification within the species appears to have occurred primarily during the Pleistocene. The data partially support a hypothesis of multiple waves of diversification following the climatic fluctuations of glacial and interglacial periods. Speyeria callippe was found to be paraphyletic containing both Speyeria egleis and Speyeria edwardsii. The genetic variation observed within S. callippe was highly structured reflecting local geography. However, this did not extend to larger scales as subspecies and major color pattern groups were not recovered as monophyletic, consistent with the large amount of overlapping morphological variation. Overall, intraspecies differentiation in morphology and mtDNA observed here indicate S. callippe is a young species complex with potentially adaptive color pattern variation that is in a relatively early stage of sorting into geographically separate entities.
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Willig, Judith A. (Judith Ann) 1953. "Paleo-archaic broad spectrum adaptations at the Pleistocene-Holocene boundary in Far Western North America." Thesis, University of Oregon, 1989. http://hdl.handle.net/1794/9220.
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xx, 463 p. : ill., maps. Two print copies of this title are available through the UO Libraries under the call number: KNIGHT E61 .W72 1989<br>Western Clovis and Western Stemmed cultural traditions, archaeologically indexed by fluted (Clovis) and stemmed projectile point complexes, represent the earliest human occupation documented in Far Western North America. The temporal closeness of Western Clovis, dated roughly from 11,500 to 11,000 B.P., to Western Stemmed complexes known as early as 11,140 to 10,800 B.P., has generated debate over the age and historical relationship of these cultures. The frequent co-occurrence of fluted and stemmed points along the lowest strandlines in pluvial lake basins has also led scholars to hypothesize an early development of the characteristically "Archaic" lake-marsh adaptations known from later periods.
Geoarchaeological research in the northern Alkali Lake Basin of south-central Oregon has addressed these issues of cultural chronology and economy by seeking data to test a paleoecological model of human land use in the basin from 11,500 to 7,000 B.P. The model posits a late Pleistocene Western Clovis settlement oriented to a small, shallow lake or pond, followed by an early Holocene Western Stemmed occupation around a much larger lake and marsh fringe.
Data gathered through basin-wide site survey, stratigraphic studies, and high-resolution mapping of lake features and artifacts, support the model as proposed, and reveal a settlement pattern indicative of a "tethered" focus on local lake-marsh habitats. Research also verifies the horizontal separation of fluted and stemmed artifacts on different, sequent shorelines, indicating that Western Clovis occupation precedes Western Stemmed, although the two are close in time.
Data from Alkali Basin, and elsewhere, support the notion that Far Western cultures developed broad-spectrum adaptations much earlier than was once thought. This implies that the foundations of the Western Archaic were already in place by 11,000 B.P. In keeping with the adaptive flexibility embodied within the Desert Culture concept, environmental data further suggest that this "paleo-Archaic" lifeway developed quickly, not gradually, in response to punctuated climatic change and the emerging mosaic of regional habitats which characterized the Pleistocene-Holocene boundary, at a time when the desert as we know it was just coming into being.<br>Adviser: Aikens, C. Melvin
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Hester, Dean Armstrong. "A review of the Paleogene eusuchian crocodyliform Borealosuchus wilsoni (Mook, 1959) from western North America." Thesis, University of Iowa, 2018. https://ir.uiowa.edu/etd/6131.
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Borealosuchus Brochu 1997 was erected for a group of Late Cretaceous through early Eocene eusuchian crocodyliform species formerly assigned to Leidyosuchus Lambe 1907. Borealosuchus wilsoni was originally described by Mook (1959) based solely on a dorsoventrally crushed skull from the early Eocene (Wasatchian) Green River Formation of Wyoming, and assigned to Leidyosuchus. Later analyses referred specimens from the late Paleocene and middle Miocene to the species (Brochu, 1997). In phylogenetic analyses, Borealosuchus has been retrieved as either a basal crocodylian (e.g., Salisbury and Willis, 1996; Brochu, 1997; Wu et al., 2001; Buscalioni et al., 2011; Brochu et al., 2012; Narváez et al., 2016) or a close crocodylian outgroup (e.g. Benton and Clark, 1988; Pol et al., 2009; Turner and Pritchard, 2015). More exact phylogenetic placement of Borealosuchus remains unclear. Borealosuchus wilsoni is stratigraphically the youngest species of Borealosuchus, and one of the most completely known, and as such, it figures prominently in ongoing debates over the phylogenetic relationships and origin of crown group Crocodylia. Given its long stratigraphic range in the literature, the question of whether specimens currently referred to B. wilsoni all pertain to a single species is open.
This study focuses on a more thorough description of the skeletal morphology of Eocene Borealosuchus, and a revision of the taxonomy of this assemblage, including the conspecific nature of Wasatchian Borealosuchus wilsoni and middle Eocene (Bridgerian) fossils referred to Borealosuchus wilsoni, including material of Diplocynodon stuckeri Mook 1960. A phylogenetic re-assessment of B. wilsoni will hopefully provide further resolution within Borealosuchus and among other closely related taxa.
Specimens were coded with a matrix of 190 morphological characters and subjected to phylogenetic analysis. The diversity of Borealosuchus during the Eocene has been underestimated and specimens from the Bridgerian are diagnosable and distinct from those of the preceding Wasatchian stage. A new species will be erected to contain this material. The erection of a new species of Eocene Borealosuchus renders the holotype of D. stuckeri non-diagnostic at the species level, and a new holotype USNM 12990 is designated for Bridgerian Borealosuchus. Some specimens assigned to Brachyuranochampsa eversolei and Crocodylus affinis may also be referable to Borealosuchus. The addition of new material to Borealosuchus increases the diversity of this group during the Eocene.
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Them, II Theodore Roland. "Biogeochemical Cycling and Paleoenvironmental Reconstructions of the Toarcian Oceanic Anoxic Event from Western North America." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/81908.
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The Toarcian Oceanic Anoxic Event (T-OAE; ~183 million years ago) represents an interval during the Mesozoic when the emplacement of the Karoo-Ferrar Large Igneous Province (LIP) is thought to have resulted in significant environmental change. Associated with this interval was the widespread deposition of organic-rich sediments, carbon cycle and seawater chemistry changes, global warming, the development of marine anoxia, and major extinction events. The majority of studies of this event that have documented these responses have come from the Boreal and Tethyan regions of Europe, thus casting some doubt to the regional versus global significance of the event. Thus my dissertation has sought to reconstruct biogeochemical and paleoenvironmental changes across the T-OAE from a sedimentary succession that was deposited on the margins of a different ocean basin away from the well-studied European successions. Specifically, I have studied the chemostratigraphy of the Fernie Formation of the Western Canada Sedimentary Basin (WCSB), which was deposited on the eastern margin of the Panthalassa Ocean. The Toarcian carbon isotope excursions (CIEs) in the WCSB confirm that these features are global phenomena. I have suggested a new driver for small-scale CIEs observed during the event: the release of wetland-derived methane during progressive global warming. The osmium isotope record and numerical modeling of the osmium cycle suggests that continental weathering rates increased during the T-OAE by 230 – 540%. Rhenium abundance data also suggests that the increased geographic extent of marine anoxia during the T-OAE caused a global drawdown in the seawater rhenium inventory. Iron speciation data are used to reconstruct redox conditions within the WCSB, which suggest ferruginous conditions developed in the more distal locations at the onset of the T-OAE before returning to euxinic (anoxic and sulfidic) conditions. This is likely related to enhanced pyrite burial on a global scale, which caused the drawdown of the seawater sulfate inventory, thus limiting pyrite formation in the distal locations. The proximal setting remained euxinic across the T-OAE, and in all locations the iron speciation data suggest anoxic conditions persistent well after the interval that has been traditionally called the end of the T-OAE.<br>Ph. D.
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Lin, Alexander Jih-Pai. "Systematics and taphonomy of Naraoia and Skania (Arthropoda) from Guizhou, China, and Western North America." The Ohio State University, 2003. http://rave.ohiolink.edu/etdc/view?acc_num=osu1407397460.
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Walker, Mindy Lynn. "Mitochondrial-DNA variation and the evolutionary affinities of the Peromyscus maniculatus complex from western North America." Diss., Texas A&M University, 2005. http://hdl.handle.net/1969.1/3216.
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Intraspecific phylogeography and the phylogenetic relationships of recently-diverged taxa are best assessed with the use of a genetic marker that coalesces rapidly and thus provides phylogenetically informative characters for closely-related taxa. Mitochondrial DNA (mtDNA) fits these criteria and was thereby ideal for analyzing genetic variation within and among the youngest taxonomic members of the Peromyscus maniculatus species group, P. sejugis (restricted to two islands in the Sea of CortÃÂés), P. maniculatus (distributed throughout North and Central America) and P. keeni (a coastal species restricted to the Pacific Northwest of North America). The approach utilized in this research involved sequencing a 1439 base-pair (bp) region of mtDNA for a total of 581 specimens representing 45 different geographic localities from along the west coast of North America. The sequences obtained were used to assess the partitioning of genetic diversity within and among these taxa, address phylogenetic and taxonomic concerns about the western representatives of the P. maniculatus species group and discuss the post-Pleistocene biogeography of the west coast of North America. Analysis of mtDNA sequence variation, considered within the framework of a phylogenetic species concept, revealed the existence of two evolutionarily significant units of P. sejugis as well as a previously unrecognized sibling species nested within the Pacific coastal range of P. maniculatus. Moreover, analysis of intraspecific sequence divergence allowed for the identification of the ice-free refugium thought to harbor P. keeni throughout glaciation during the Pleistocene epoch. This work will establish the foundation for additional examination of cryptic genetic variation in different morphotypes of P. maniculatus and continue the precedent for recognizing P. maniculatus-group taxa that reflect true evolutionary entities.
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Byun, S. Ashley. "Quaternary biogeography of western North America insights from mtDNA phylogeography of endemic vertebrates from Haida Gwaii /." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/ftp02/NQ37334.pdf.
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Oh, Sun Yeong. "Phylogenetic Relationships of Cottids (Pisces: Cottidae) in Upper Snake River Basin of Western North America." BYU ScholarsArchive, 2016. https://scholarsarchive.byu.edu/etd/6228.
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Freshwater sculpins (Cottus) are common throughout temperate regions of the Northern Hemisphere. Their broad distribution in the Western North America makes them a good model for understanding phylogeographic relationships among western fishes. Within much of the interior west three lineages, C. bairdii, C. confusus, and the C. beldingii complex, are most prevalent. The distribution of these three overlap in the Snake River Basin. All occur below Shoshone Falls on the Snake River. However, only two currently reside in the Upper Snake River above the falls. An exception are the Lost River streams of central Idaho. While these streams are technically part of the Upper Snake River Basin, they do not directly connect with the Snake River. Preliminary studies with a single mitochondrial DNA (mtDNA) gene suggested multiple pathways for Cottus introduction into the Lost River stream complex. Here, three mitochondrial and five nuclear genes were examined to investigate the phylogenetic relationships of these three lineages. Sequences were obtained from 71 different populations in the Lost River streams and surrounding basins. Maximum Likelihood (ML) phylogenies were constructed using these data. Our data indicate that relationships among populations within these species are complex and that no single invasion into the Lost River streams and surrounding regions can account for the phylogenetic signals detected. Instead, it appears that multiple invasions in an evolving landscape played a significant role in the modern distribution of species in this region.
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Darr, Molly Norton. "Biological Studies and Evaluation of Scymnus Coniferarum, a Predator of Hemlock Woolly Adelgid from Western North America." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/77950.
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The hemlock woolly adelgid (HWA), Adelges tsugae Annand, is an invasive pest of eastern hemlock, Tsuga canadensis (L.) Carriere and Carolina hemlock Tsuga caroliniana Englem. in the eastern United States. A newly reported beetle predator for HWA, Scymnus (Pullus) coniferarum Crotch (Coleoptera: Cocinellidae) preys on the pest in the western United States, and was approved for release in the eastern United States for the control of HWA. This research investigated the viability of S. coniferarum as a biological control agent of A. tsugae in the eastern United States, as well as the ecological dynamics between S. coniferarum and host prey species in its native range of western North America.
In objective one, S. coniferarum predation, reproductive potential, and survival were evaluated in field-cages on adelgid infested T. canadensis in southwestern Virginia. Adult S. coniferarum fed on both generations and all life stages of A. tsugae at rates comparable to other adelgid-specific predators, and survived for extended periods of time in the field. In objective two, host-range tests for S. coniferarum were conducted in a series of no-choice and paired-choice feeding, oviposition, and development studies. Scymnus coniferarum adults fed on all adelgid species, and completed development on HWA and Adelges piceae Ratz. Scymmnus coniferarum oviposition was extremely low. In the final objective, Douglas-fir, Pseudotusga menziesii Mirb., Shore pine, Pinus contorta Dougl., western white pine, Pinus monticola Dougl., and western hemlock, Tsuga heterophylla (Raf.) Sarg. host tree species were sampled in Tacoma, Washington to investigate the life history of S. coniferarum and associated adelgid prey species in the western United States. Scymnus coniferarum adults were found on both pine species, Douglas fir, and western hemlock, and seemed to move between host tree species seasonally. Each host tree supports a different adelgid species, and a limited diet of strictly HWA in host-range tests could have contributed to low oviposition rates.
This study suggested that S. coniferarum is a voracious predator of HWA in the field and laboratory. However, S. coniferarum laid very few eggs in laboratory studies, and zero eggs were recovered in field-cage analyses. This suggested that S. coniferarum may rely on multiple adelgid species to reproduce and establish in the eastern United States.<br>Ph. D.
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Shaw, Hunter D. "For home and country Confederate nationalism in western North Carolina." Master's thesis, University of Central Florida, 2010. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4583.
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This study examines Confederate nationalism in Western North Carolina during the Civil War. Using secondary sources, newspapers, civilian, and soldiers' letters, this study will show that most Appalachians demonstrated a strong loyalty to their new Confederate nation. However, while a majority Appalachian Confederates maintained a strong Confederate nationalism throughout the war; many Western North Carolinians were not loyal to the Confederacy. Critically analyzing Confederate nationalism in Western North Carolina will show that conceptions of loyalty and disloyalty are not absolute, in other words, Appalachia was not purely loyal or disloyal.<br>ID: 029050263; System requirements: World Wide Web browser and PDF reader.; Mode of access: World Wide Web.; Thesis (M.A.)--University of Central Florida, 2010.; Includes bibliographical references (p. 146-151).<br>M.A.<br>Masters<br>Department of History<br>Arts and Humanities
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Ferguson, Elizabeth, and University of Lethbridge Faculty of Arts and Science. "Einstein, sacred science, and quantum leaps a comparative analysis of western science, Native science and quantum physics paradigm." Thesis, Lethbridge, Alta. : University of Lethbridge, Faculty of Arts and Science, c2005, 2005. http://hdl.handle.net/10133/253.
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Science is curiosity about the natural world translated into knowledge; it serves to identify laws and validate hypotheses. The quest for knowledge is influenced by the paradigm of the scientist. The primary object of this study is to examine Quantum Mechanics and Sacred/Native science for similarities and differences. This will be accomplished through an extensive use of authorities from both Western and Native sciences in an in depth examination of the paradigms upon which their foundations are based. This study will explore language and how language used leads the scientist down a particular pathway. This study will conclude in a summary fashion, an exploration of a few select key concepts from both Native and Western sciences from a comparative perspective.<br>ix, 135 leaves ; 29 cm.
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Banholzer, Sandra. "The Central Pacific El Niño and its impact on weather and forest fire patterns in western North America." Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42949.
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The El Niño/ Southern Oscillation (ENSO) is known to influence the weather in western North America through teleconnections. Several studies have established a relationship between ENSO and forest fire occurrence. However, a recently discovered variant of ENSO, called Central Pacific El Niño, may cause a different teleconnection and forest fire pattern.
Investigating and classifying past El Niño events and their possible influence on weather and forest fire patterns in western North America from 1981-2010 was the objective of this study.
The analysis revealed that current El Niño classification methods are suboptimal and that a binary distinction leads to misclassification of events. It, however, confirms that the two types show a different warming pattern as well as different wind and precipitation patterns.
These characteristics of the Central Pacific El Niño can cause different extra tropical teleconnections in western North America than the canonical El Niño. Variation of teleconnections within the events and the limited amount of events, however, complicate a clear conclusion. Further, other oscillations such as the Arctic Oscillation play a major role in impacting the climate in western North America.
Exploratory analysis of natural forest fires of North America identified hot spots of annual area burned in central Alaska, north-west and central Canada and western United States. Further, singular value decomposition and spatial correlation analysis revealed a different teleconnection response in summer drought patterns over western North America related to the two types of El Niño. The drought pattern is significantly related with forest fire frequency and area burned in certain regions across western North America. A clear connection between the different El Niño types and the forest fire pattern however remains inconclusive.
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Girardi, James Daniel. "Comparison of Mesozoic Magmatic Evolution and Iron Oxide (-Copper-Gold) (`IOCG') Mineralization, Central Andes and Western North America." Diss., The University of Arizona, 2014. http://hdl.handle.net/10150/319881.
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Mesozoic Cordilleran arc magmatism along the western margins of North and South America shows similar patterns of episodic activity, but differences in tectonic setting, in composition, and in peak magnitudes of magma fluxes. The development of iron oxide(-copper-gold) (‘IOCG’) mineralization accompanies the pulse of arc magmatism in North and South America, but is most prolific during the early to middle Mesozoic pre-orogenic phases of the Cordillera. The focus of this work is to better understand the episodic nature of Cordilleran magmatism, controls to magma sources and compositions, and controls to Cordilleran IOCG mineralization. The objectives of this study are accomplished by focusing on two regions of the Cordillera that experienced similar early-middle Mesozoic tectonic settings, but display very different magmatic fluxes, compositions, and development of IOCG systems. The Coastal Batholith of northern Chile was investigated for the timing, composition, and fluxes of magmatism at three scales of observation including 1:1M scale between ~18°S to 34°S, 1:100K scale between 26°S to 28°S, and 1:20K scale along a transect at ~27.5°S where new major elemental, trace elemental, and Nd, Sr, and O isotope data were acquired. From the western United States magmatic fluxes and compositions were compiled from the literature, as were characteristics of Jurassic IOCG occurrences in the central Mojave Desert, California. Geologic framework analysis at 1:250K scale and new 1:5K scale mapping of the hydrothermal features associated with Jurassic IOCG occurrences were conducted in the central Mojave Desert, California. Results from northern Chile reveal that the Coastal Batholith formed in a dominantly extensional setting, had episodic magma fluxes that were dominantly mafic (dioritic-quartz dioritic) during peak output, and has uniformly depleted mantle-like Nd and Sr isotopes regardless of magma composition. Published compilations from coeval arcs of North America indicate that they display the opposite relationships to Chile between tectonic setting, magmatic fluxes, and magmatic compositions. Results from mapping in the southern Palen Mountains, California, and synthesis of composite exposures across the central Mojave Desert, California demonstrates that IOCG systems in this region are vertically zoned and genetically related Jurassic intrusions ranging from diorite/gabbro to granite in composition. The mineralized occurrences have intermediate depth (1–4 km), cores of magnetite±hematite mineralization with sparse Fe(-Cu) sulfides, and zone upward to acid-altered tops and downward to Fe-depleted, metal-poor, Na±Ca-altered roots. These patterns resemble those observed in IOCG systems throughout the Cordillera of the Americas.
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Slattery, Mico T. "Towards a comparative study of the concept of mind/consciousness in Western science, Eastern mysticism and American Indian thought." Diss., Connect to online resource - MSU authorized users, 2008.
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Bollinger, Susan Marie. "FAME -Families Achieving Mathematical Excellence the process of developing a family involvement program for a Western rural middle school serving American Indian students /." Thesis, Montana State University, 2010. http://etd.lib.montana.edu/etd/2010/bollinger/BollingerS0510.pdf.
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Family is an important element in the cultural identity of this American Indian community so involving families in the education of their children is crucial. This mixed methods study documents the process of implementing a family involvement program at a rural school serving predominantly low-income families near an American Indian reservation. The results showed there is a strong sense of responsibility among the parents for the education of their children. Parents and students were found to work together to improve their learning by reviewing homework together and doing learning activities at home. Interview data stressed the importance of developing a welcoming learning environment at school and at afterschool events that is culturally sensitive. Families need to feel they are welcomed and respected. The structure of afterschool events must be flexible and familiar for continued participation. Facilitators of family involvement programs in American Indian communities need to design programs that are culturally responsive to the local tribe and community, supporting the comfort and learning of the participants, providing materials for everyone to take home, and bringing the program to the people.
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McCreary, Cheryl S. "Genetic Relationships, Morphological Divergence and Ecological Correlates in Three Species of the Viola canadensis Complex in Western North America." View online, 2005. http://etd.ohiolink.edu/send-pdf.cgi/McCreary%20Cheryl%20S.pdf?acc_num=ohiou1133550610.
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Minckley, Thomas A. "Holocene environmental history of the northwestern Great Basin and the analysis of modern pollen analogues in western North America /." view abstract or download file of text, 2003. http://wwwlib.umi.com/cr/uoregon/fullcit?p3113019.
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Thesis (Ph. D.)--University of Oregon, 2003.<br>Typescript. Includes vita and abstract. Includes bibliographical references (leaves 294-310). Also available for download via the World Wide Web; free to University of Oregon users.
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Douglas, M. R., M. A. Davis, M. Amarello, et al. "Anthropogenic impacts drive niche and conservation metrics of a cryptic rattlesnake on the Colorado Plateau of western North America." ROYAL SOC, 2016. http://hdl.handle.net/10150/617208.
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Ecosystems transition quickly in the Anthropocene, whereas biodiversity adapts more slowly. Here we simulated a shifting woodland ecosystem on the Colorado Plateau of western North America by using as its proxy over space and time the fundamental niche of the Arizona black rattlesnake (Crotalus cerberus). We found an expansive (= end-of-Pleistocene) range that contracted sharply (= present), but is blocked topographically by Grand Canyon/Colorado River as it shifts predictably northwestward under moderate climate change (= 2080). Vulnerability to contemporary wildfire was quantified from available records, with forested area reduced more than 27% over 13 years. Both 'ecosystem metrics' underscore how climate and wildfire are rapidly converting the Plateau ecosystem into novel habitat. To gauge potential effects on C. cerberus, we derived a series of relevant 'conservation metrics' (i.e. genetic variability, dispersal capacity, effective population size) by sequencing 118 individuals across 846 bp of mitochondrial (mt)DNA-ATPase8/6. We identified five significantly different clades (net sequence divergence = 2.2%) isolated by drainage/topography, with low dispersal (F-ST = 0.82) and small sizes (2N(ef) = 5.2). Our compiled metrics (i.e. small-populations, topographic-isolation, low-dispersal versus conserved-niche, vulnerable-ecosystem, dispersal barriers) underscore the susceptibility of this woodland specialist to a climate and wildfire tandem. We offer adaptive management scenarios that may counterbalance these metrics and avoid the extirpation of this and other highly specialized, relictual woodland clades.
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Reim, Sabine. "Emerging patterns of specialisation in the global networks of incumbent air carriers from Asia -Pacific, North America and Western Europe." Thesis, University of Reading, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.430910.
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Safaee, Samira. "Developing global dataset of salt pans and salt playas using Landsat-8 imagery: a case study of western North America." Thesis, Kansas State University, 2017. http://hdl.handle.net/2097/38558.
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Master of Arts<br>Department of Geography<br>Jida Wang<br>Monitoring salt pans is important especially for agricultural management in arid or semi-arid regions because salt pans can negatively affect human life, wildlife, and ecology. Some of the harmful impacts of salt pans are accelerated desertification, cropland loss, economic downturn, wildlife loss, and forced migration of humans and animals due to salt storms. Spectral salt pan indices based upon remotely sensed data (using spectral properties of Landsat-8 imagery) suggested in previous studies vary by location. In other words, the spectral configuration of a salt index for a given location may not be readily applicable to another location due to spatial heterogeneity of salt components across the continental surface. Using Landsat-8 OLI imagery and climate data sets, this study aims to develop a mapping framework which can effectively extract salt pans and salt playas under various spectral conditions in different geographic locations. Based on training samples selected in eight major salt pans/playas in North America, Central Asia, Africa, and Australia, the mapping framework was designed to include the following steps: i) a conservative salt index to highlight potential salt-covered regions, ii) a calibrated support vector machine (SVM) to extract high-salinity areas in the mask regions, and iii) a posterior quality assurance/ quality control (QA/QC) with assistance of auxiliary datasets (e.g., surface slope and land covers) to eliminate commission errors and refine the extracted saltpan areas.
The developed mapping framework was validated in the arid endorheic regions across the western United States, with a total area of 699 thousand square kilometers. Both qualitative and quantitative assessments of the results show reliability of the developed framework. The overall accuracy of the extracted salt pans prior to QA/QC is 97%. The final product after QA/QC achieves an overall accuracy of 99.95% and a Kappa statistic of 0.99.According to the results of salt pans areas and endorheic basins areas, it can be concluded that two aforementioned variables of this study are positively correlated to each other, and 1.10 percent of the entire case study area is covered by salt pans. The accuracy of the results suggests a potential that the mapping framework, together with the collected training sample and algorithms, may be applicable to identify salt pan and salt playa regions across the Earth’s land surface.