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Title: An approach to remotely monitor glacier mass balance at seasonal to annual time scales, Columbia and Rocky Mountains, Canada
Contributors: Ben Mauri Pelto (author), Menounos Brian (thesis advisor), Matt Reid (chair), Shawn Marshall (committee member), Peter Jackson (committee member), Stephen Dèry (committee member), Roger Wheate (committee member), Gwenn Flowers (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
Abstract: My dissertation investigates glacier mass change in the Columbia and Rocky Mountains of British Columbia. In chapter one I discuss the importance of the cryosphere and glaciers, introduce the climate and glaciers of the study region, and outline the objectives and structure of this dissertation. Previous work established the feasibility of geodetic methods to accurately produce winter glacier mass balance and annual glacier mass balance. These studies demonstrate that geodetic surveys can be used to estimate mass balance during the accumulation season or for one glacier over a number of years. In chapter two, I refine these published methods to measure seasonal and annual mass balance for six glaciers within two mountain ranges from 2014–2018. I use synchronous field-based glaciological measurements, airbornelaser scanningsurveys (ALS) and satelliteimagery to quantify seasonal glacier mass change from 2014–2018. Chapter three reports on radar surveys I completed of the study glaciers, adding important observations to the global database of ice thickness. I use these observations and an existing flowline model, driven with observations of surface mass balance and glacier elevation to bias-correct ice thickness estimates for each glacier. Finally, I use the model to estimate ice thickness for all glaciers in the Columbia Basin and estimate total ice volume. Chapter four builds upon previous work which used surface topography, glacier mass balance, ice thickness, and ice velocity data to estimate ice flux at discrete glacier cross-sections. Previous efforts to infer the spatial distribution of mass balance have focused on glacier tongues. I expand upon this method, calculating surface mass balance between flux gates over the entire elevation range of three glaciers, over three years. I derive the altitude-mass balance relation and demonstrate that the relation can be accurately described with high-resolution elevation and ice flux data, and suggest that this method can be expanded for large-scale estimates. Chapter five summarizes the study’s major findings, highlights its limitations and discussed its broader implications. Finally, I make recommendations that will address knowledge gaps, and improve our understanding of changing glacier conditions and ability to model glacier dynamics.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2020

Title: Role of atmospheric rivers on the hydrology of western Canada
Contributors: Aseem Raj Sharma (author), Stephen Dery (thesis advisor), Margot Parkes (chair), Ellen Petticrew (committee member), Brian Menounos (committee member), Alex Cannon (committee member), John Gyakum (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
Abstract: Atmospheric rivers (ARs) are synoptic-scale atmospheric phenomena that transport moisture from the (sub)-tropical regions to the mid-latitudes globally. They play a substantial role on water resources of British Columbia and southeastern Alaska (BCSAK). However, understanding of their climatology and impacts on the hydrology of this region remains limited. I use a combination of a regional AR catalog, reanalysis datasets, gridded precipitation, observed river runoff data, and topographic information, to provide insights on the climatology of landfalling ARs (LARs) and to quantify changes in the contribution of LARs to the precipitation, river runoff, and their extremes in BCSAK. Each year BCSAK experiences, on average, 35±5 LARs with the highest number in autumn (13±2) and an average duration of 2±1.8 days. The 1979-2016 average annual counts of LARs increase by ~20% across BCSAK. Slightly higher numbers of LARs occur during the neutral phase of El Niño-Southern Oscillation, the positive phases of the Pacific Decadal Oscillation and the Pacific-North American Pattern, and the 2013/2014 warm anomaly of the Northeastern Pacific. LARs contribute 13% (spatial range: <5-33%) and 36% (spatial range: <5-97%) of annual total and extreme precipitation, respectively, across BCSAK with higher values over elevated terrain. AR-related precipitation days increase during 1979-2012; however, no change occurs in the average AR-related precipitation amount for most of BCSAK. LARs contribute 14±6% (spatial range: 2%-29%) and 48±24% (spatial range: ~10%-100%) of the total annual and annual maxima runoff in the watersheds of BCSAK. ARs control the distribution of peak runoff in most of BCSAK with >60% of the 168 watersheds analyzed having >5 of the top 10 annual maxima runoff associated with them. My work presents a baseline assessment of the AR regional climatology in BCSAK, provides the proportion of hydrological processes attributed to ARs, and assesses changes in those linkages over time. This work is useful to associate future climate model simulations, extreme weather forecasting, seasonal predictions, and water issues including flood mitigation, hydro-power generation, industrial water use, and ecological, recreational, and cultural water values of western Canada where rapid climate-induced hydrological changes are occurring.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2020

Title: Assessing the effects of uncertainty and climate change on hydrological simulations across a permafrost gradient in North-Central Canada
Contributors: Rajtantra Lilhare (author), Stephen Dery (thesis advisor), Tricia Stadnyk (thesis advisor), Roger Wheate (chair), Phil Owens (committee member), Xiaogang (John) Shi (committee member), Francis Zwiers (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
Abstract: Hudson Bay, a vast inland sea in northern Canada, receives the highest average annual freshwater from the Nelson River system among all other contributing rivers. A rapidly changing climate and flow regulation from hydroelectric developments alter Nelson River streamflows timing and magnitude, affecting Hudson Bay’s physical, biological, and biogeochemical state. Despite recent developments and advances in climate datasets, hydrological models, and computational power, modelling the Hudson Bay system remains particularly challenging. Therefore, this dissertation addresses crucial research questions from the Hudson Bay System (BaySys) project by informing how climate change impacts variability and trends of freshwater-marine coupling in Hudson Bay. To that end, I present a comprehensive intercomparison of available climate datasets, their performance, and application within the macroscale Variable Infiltration Capacity (VIC) model, over the Lower Nelson River Basin (LNRB). This work aims to identify the VIC parameters sensitivity and uncertainty in water balance estimations and investigates future warming impacts on soil thermal regimes and hydrology in the LNRB. An intercomparison of six climate datasets and their equally weighted mean reveals generally consistent air temperature climatologies and trends (1981–2010) but with a prominent disagreement in annual precipitation trends with exceptional wetting trends in reanalysis products. VIC simulations forced by these datasets are utilized to examine parameter sensitivity and uncertainties due to input data and model parameters. Findings suggest that infiltration and prescribed soil depth parameters show prevailing seasonal and annual impacts, among other VIC parameters across the LNRB. Further, VIC simulations (1981–2070) reveal historical and possible future climate change impacts on cold regions hydrology and soil thermal conditions across the study domain. Results suggest that, in the projected climate, soil temperature warming induces increasing baseflows as future warming may intensify infiltration processes across the LNRB. This dissertation reports essential findings in the application of state-of-the-art climate data and the VIC model to explore potential changes in hydrology across the LNRB’s permafrost gradient with industrial relevance of future water management, hydroelectric generation, infrastructure development, operations, optimization, and implementation of adaptation measures for current and future developments.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2020

Title: Climate change-conscious systematic conservation planning
Contributors: Jerrica Mann (author), Pamela Wright (thesis advisor), Zoë Meletis (chair), Katherine Parker (committee member), Roger Wheate (committee member), Jodi Hilty (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
Abstract: The synergistic effects of anthropogenic disturbance, habitat fragmentation and climate change pose a significant threat to biodiversity that is challenging to predict. Anthropogenically driven climate change has already begun to impact critical climate regions and is now recognized to be one of the most serious threats to biodiversity and the conservation thereof. Despite this, few conservation planning initiatives have sought to sharpen the focus of the systematic conservation planning (SCP) framework to explicitly include climate change. To promote the evolution of the SCP framework into a climate change-conscious (CCC) approach to conservation planning, I developed and applied a methodology for incorporating climatechange resiliency into the SCP framework. This CCC-SCP methodology can be used to guide future conservation planning initiatives, helping conservation planners recognize and respond to opportunities for action, conserve our planet’s biodiversity and mitigate the effects of climate change.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2020

Title: White spruce growth sensitivity to climate variability in pure and mixedwood stands
Contributors: Jéssica Chaves Cardoso (author), Che Elkin (thesis advisor), Peter Jackson (chair), Paul Sanborn (committee member), Sybille Haeussler (committee member), Stephen Dery (committee member), University of Northern British Columbia Natural Resources & Environmental Studies (Degree granting institution)
Abstract: It is prudent to understand how tree growth responds to climate variability to better project their growth in the current and future changes in climate in boreal forests. In this thesis, I studied how climate variables influence individual white spruce trees (Picea glauca (Moench) Voss) over short and intermediate periods in pure and mixedwood stands in northeastern British Columbia. In Chapter 2, I studied the importance and the influence of annual, seasonal, and monthly microclimate variables on the annual growth of white spruce trees in pure and mixedwood stands. In Chapter 3, I studied the importance and the influence of microclimate variables on sap flow of white spruce trees through different time scales in these two stand types. My key finding in these two chapters is that stand composition and structure are essential determinants of how spruce radial growth and sap flow respond to fluctuations in climate variables, and how they will respond to projected future climate scenarios. A combination of warmer temperatures and drought during summer will negatively affect white spruce trees growth in pure and mixedwood stands in the studied region. Spruce sap flow in both stand types is likely to increase as the climate warms, increasing the demand for soil water. As this resource becomes less available, white spruce in both stand types are likely to respond with processes that can compromise their physiological integrity. White spruce growing in mixedwood stands might be more sensitive to drought stress than in pure stands due to the higher competition for limiting resources (primarily water). This thesis provides information of expected changes in tree growth to climate variability and demonstrates the importance of appropriate site selection to plant spruce trees and management of pure and mixedwood stands.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2020

Title: The relationship between climate and outbreak dynamics of Dothistroma needle blight in northwest British Columbia, Canada.
Contributors: Cedar Welsh (author), Kathy Lewis (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: No abstract available.
Discipline: Biology
Content Model: info:fedora/ir:thesisCModel
Date added: 2007

Title: Community adaptation to climate change: An exploration of climate change adaptation planning in British Columbia.
Contributors: Ian Picketts (author), John Curry (Thesis advisor), Eric Rapaport (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Planners in British Columbia must adapt to climate change by preparing for expected and unexpected changes in their communities. The results of survey and workshop research conducted at the Planning Institute of BC conference indicate that planners do not have a high level of knowledge of climate change adaptation. Planners feel that the impacts that will affect BC the most in 50 years will be related to forests, agriculture, river flooding, transportation and water. Different regions in the province will be affected in different ways, and adaptation strategies must be created for the specific needs and attributes of a community. Open-structured workshops are a good method to educate planners about climate change adaptation however, they should not be expected to yield results that can be incorporated into planning documents. Global climate models are a valuable tool that decision makers can use to help determine appropriate planning actions. --P. ii.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2010

Title: Using bioclimatic envelope modelling to incorporate spatial and temporal dynamics of climate change into conservation planning.
Contributors: Nancy-Anne Rose (author), Philip Burton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Current and predicted trends in climate are diverging from historic norms, thereby compromising the equilibrial basis of our resource management frameworks. This study investigates the impacts of climate change on biodiversity in the context of conservation planning for British Columbia's Central Interior. I used bioclimatic envelope modeling and a climate interpolation and general circulation model downscaling tool to assess 73 rare plant species, 103 biogeoclimatic variants, and 30 terrestrial ecosystem units. I mapped areas projected to support climate suitable for the persistence of those conservation targets through to the 2080s. Results illustrate the potential for disruptive change only 12% (24) of the 206 targets are projected to experience persistent climate at their current locations. Although strong overlap among locations projected to persist for different targets was not found, and those areas meeting multiple objectives (including value independent of climate change) are clear priorities for protection. This methodology can function as a valuable tool for conservation planners and resource managers. --P. [i]
Discipline: Biology
Content Model: info:fedora/ir:thesisCModel
Date added: 2010

Title: Pragmatism, projections, priorities, plans and politics in Prince George: Adapting to climate change in a Canadian community.
Contributors: Ian M. Picketts (author), Stephen Dery (Thesis advisor), John Curry (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: The two principal human responses to climate change are adaptation and mitigation. A small, but growing, number of scientific and professional efforts are focusing toward adaptation, as it becomes clear that mitigation efforts alone can no longer effectively minimize the negative impacts of climate change. Local governments are well suited to undertake proactive adaptation measures due to their abilities to apply social capital, act quickly, and implement actions that can provide direct benefits for residents. Like many northern communities, the City of Prince George, Canada, has been experiencing rapid rates of climate change. City practitioners have been responding to changing conditions in the region for years, and expressed interest in formally exploring adaptation with researchers. During a focused one-day workshop, an overview of climate change and past climate trend and future projection information were presented to local staff and stakeholders, and applied to determine impact priorities. The workshop outcomes were triangulated with community feedback to create an adaptation strategy for Prince George. Changes to forests and increased flooding are the top local priorities, and impacts related to transportation infrastructure, severe weather and water supply are high priorities. Other impacts, such as agricultural changes, are important but did not rank highly using a risk assessment framework. The adaptation strategy precipitated further local engagement and action. Researchers participated in the processes to create a sustainability plan and update the Official Community Plan for Prince George. Many adaptation measures were integrated into both documents. Factors enabling the incorporation of adaptation included the high level of local knowledge and existing adaptation strategy. Many barriers, including limited policy direction and a lack of priority, continue to pose challenges in mainstreaming adaptation into local plans. Additional research focused on forests, flooding, transportation infrastructure
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2014

Title: Environment, climate and tree growth relationships at the western Canadian Arctic treeline.
Contributors: Sean P. Sweeney (author), Scott Green (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: The latitudinal forest-tundra ecotone is an area that is experiencing substantial changes with respect to tree growth and climate change. We examined the response of radial tree growth to climate in adjacent regions of northern Yukon and Northwest Territories, Canada, across environmental and spatial gradients using dendrochronological methods. Principal components analysis was used to derive the primary modes of variation in the tree-ring records, which were subsequently attributed to environmental and climatic features. We found that slope gradient (small spatial scales) and ecoregional classification (larger spatial scales) played substantial roles in determining the response of tree growth to climate. Climate correlations were found for current and previous years to growth, many of which challenge currently held assumptions regarding the dominant climatic determinants of tree growth at high latitudes. These findings indicate that Arctic forest environments are highly complex, and that expected changes in the biosphere will occur at various rates, times and places. --P. ii.
Discipline: Biology
Content Model: info:fedora/ir:thesisCModel
Date added: 2011

Title: Groundwater -- surface water interaction under the effects of climate and land use changes.
Contributors: Gopal Chandra Saha (author), Jianbing Li (Thesis advisor), Ronald Wallen Thring (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Historical observed data and future climate projections provide enough evidence that water resources systems (i.e., surface water and groundwater) are extremely vulnerable to climate change. However, the impact of climate change on water resources systems varies from region to region. Therefore, climate change impact studies of water resources systems are of interest at regional to local scales. These studies provide a better understanding of the sensitivity of water resources systems to changes in climatic variable (i.e., precipitation and temperature), and help to manage future water resources. In addition to climate change, human-induced land use changes also significantly affect water resources systems. Therefore, climate and land use changes can provide offsetting and additive impacts on water resources systems depending on the region and watershed characteristics. In this dissertation research, groundwater-surface water (GW-SW) interaction under the effects of climate and land use changes were investigated through the development of a Gridded Surface Subsurface Hydrologic Analysis (GSSHA) modeling system using a case study in Kiskatinaw River watershed (KRW), British Columbia, Canada. --Leaf i.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2015

Title: "With a connection to the land, our spirit is strong" Tlicho traditional knowledge of climate change and impacts for caribou hunting: implication for traditional knowledge research
Contributors: Petter Jacobsen (author), Chris Johnson (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: My research was to document the Elders knowledge of climate change and the impacts on caribou hunting. The Elders explained starting in the 1960-70s the weather has become warmer and drier leading to a change in hunting locations and modified hunting times. Changes to wind patterns as well as changes to snow and ice conditions have caused uncertain weather predictions and increased the community members' focus on safety. The consequence of these impacts of climate change is an increased reliance on gas and money to sustain hunting. The Tlicho Elders tied these environmental changes to human-environment interactions and interpreted these climate changes with the larger process of social changes within modern society. Based on such social perspectives of the environment, I argue that Traditional Knowledge research of climate change needs to be based on an Indigenous perception, and I provide recommendations to indigenize climate change research with sub-arctic Indigenous peoples. --P. 2.
Discipline: Interdisciplinary Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2012

Title: Trends and elevational dependence of the hydroclimatology of the Cariboo Mountains, British Columbia.
Contributors: Aseem Raj Sharma (author), Stephen Dery (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Pristine mountain environments are more sensitive to climate change than other land surfaces. The understanding of climatic variations in mountainous terrain is still uncertain. Previous studies reveal inconsistent findings on the elevational dependency of warming in the mountains. In this study, the trends and elevational dependence of climatic variables in the Cariboo Mountains Region (CMR) of British Columbia are explored. A high resolution 10 km x 10 km gridded data set of climate variables over the period of 1950-2010 is used. The Mann-Kendall test is performed for evaluation of trends and their significance. The CMR is warming at a faster rate in recent decades than regional and global warming. The minimum air temperature trend shows significant amplified warming at higher elevations. Precipitation does not show any significant trend across the study area. The possible physical mechanisms for such warming trends and the potential impacts of these changes on the endangered mountain caribou and water resources of the area are discussed. --Leaf i.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2015

Title: The influence of glacier change on sediment yield, Peyto Basin, Alberta, Canada.
Contributors: Theodore John Mlynowski (author), Brian Menounos (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: The relation between sediment yield and glacier fluctuations at timescales less than a century remains uncertain. The primary goal of this study was to assess the influence of glacier activity on sediment yield within the Peyto Lake watershed. The research focused on a small alpine watershed in the Rocky Mountains of Alberta containing Peyto Glacier and the proglacial Peyto Lake. Using photogrammetric methods I determined changes in length, area, and volume of Peyto Glacier from a topographic survey map (1917) and 18 sets of aerial photographs (1947-2005). I also collected 18 sediment cores from Peyto Lake that consists of laminated, silt-clay couplets which can be shown through ¹³⁷Cs activity to be clastic varves. Varve thickness and sediment properties were combined to produce an annual record (1917-2010) of specific sediment yield (SSY) for the watershed. I then compared the SSY record to dimensional changes of Peyto Glacier as well as available mass balance records, hydrometric records, and climate records over the study period (1917-2010). Over the period 1917-2005, Peyto Glacier retreated 2198 ± 18 m, shrank 4.0 ± 0.9 km², thinned 44 ± 31 m, and lost 581 ± 404 x 10⁶ m³ water equivalent (w.e.). I measured an additional 85 ± 4 x 10⁶ m³ w.e. of ice loss from thinning ice-cored moraines adjacent to the glacier. Over the period 1917-2005 SSY averaged 446 ± 176 Mg km²yr⁻¹, which is among the highest measured yields in the Canadian Cordillera; however, this value is relatively low for glaciated basins worldwide. The SSY record has a poor relation to short-term dimensional changes of Peyto Glacier, likely due to the complexity of sediment transfers in proglacial environments. Long-term trends in SSY are hypothesized to arise from increasing (1870-1940) and decreasing (1970-2010) glacier contribution to streamflow over the past century.
Discipline: Geography
Content Model: info:fedora/ir:thesisCModel
Date added: 2014

Title: Climate change adaptation for British Columbia Forest and Range Ecosystems : an analysis of existing research frameworks and research needs for the Future Forest Ecosystem Scientific Council (FFESC)
Contributors: Sybille S. Haeussler (author)
Abstract: "The report and its supplementary databases were initially prepared for FFESC in March 2009 to (1) identify institutional arrangements for delivering climate change adaptation research and making the results available to stakeholders, (2) assess the status of research relevant to the FFESC mandate, and (3) recommend research and delivery needs that should be addressed by FFESC ...The report provides an overview of international-to regional-level agencies and institutional networks conducting and funding climate change research relevant to BC's forest and rangeland social-ecological systems."--Executive summary.
Content Model: info:fedora/ir:citationCModel
Date added: 2010-10

Title: Late Holocene Glacier fluctuations in southernmost Patagonia.
Contributors: Malyssa Kay Maurer (author), Brian Menounos (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Documenting past climate dynamics aids in our understanding of the climate system. In order to assess future climate change it is valuable to examine the connectivity of climatic phenomena between hemispheres. Although studies that estimate past climate fluctuations are common in the Northern Hemisphere, fewer well-constrained glacier chronologies exist in the Southern Hemisphere. The assessment of past glacier activity remains the most direct method of creating a climatic record for a region, and the comparison of these glacial chronologies tests the synchronicity of climatic change between regions. This study investigates inter-hemispheric synchronicity by developing a detailed glacier history in southern Patagonia for comparison to robust glacier chronologies from the northwestern North America. Five Neoglacial advances of Stoppani Glacier in the Cordillera Darwin of southern Patagonia broadly correspond to the Neoglacial activity documented in northwestern North America. This Stoppani Glacier chronology is based on radiocarbon-dated detrital and in situ plant material contained within the northeastern lateral moraine stratigraphy. The age range from dated plant material records the first Neoglacial expansion of Stoppani Glacier which, overlaps with the end of the 4.2 ka Advance' reported throughout northwestern North America. Stoppani Glacier advanced multiple times between 3500-1900 cal yr BP which overlaps with the 'Peyto-Tiedemann Advance' documented in northwestern North America. The lacustrine record from nearby Lago Roca also suggests that local sea level lowered during the 3500-1900 cal yr BP period, resulting in the isolation of the lake from the Beagle Channel ca. 2300 cal yr BP. Plant material from within till at Stoppani Glacier and lacustrine sediments from Lago Roca yield an age range for the last advance of glaciers in the Cordillera Darwin the range coincides with the end of the wide-spread Little Ice Age Advance' documented throughout northwestern North
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2015

Title: Northern range limit mountain pine beetle (Dendroctonus ponderosae) outbreak dynamics and climate interactions in mixed sub-boreal pine forests of British Columbia.
Contributors: Kathryn H. Hrinkevich (author), Kathy Lewis (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Insect outbreaks are some of the most destructive processes of forest change with long-term economic and ecological effects that can be severe. For native insects that have co-evolved with their host forests it is important to develop and implement management strategies that are consistent with the basic ecology of the ecosystem being affected. This requires a sound ecological understanding of the disturbance regime and its function, which can only be gained through long-term stand histories appropriate to the scale of the process. This is becoming increasingly important in light of changing climate conditions which have already influenced disturbance regimes and the spatial distribution of insect ranges with unknown consequences. The objectives of this study were to develop a long-term record of mountain pine beetle (MPB) outbreaks near the northern limit of the species' range and to examine the interacting factors driving that disturbance regime. Using a combination of dendrochronological methods to reconstruct stand and outbreak history together with long-term local and large-scale climate data, I developed an integrated model of outbreak dynamics for north-central BC where little is known about the role of MPB in forest stand dynamics or the influence of climate on outbreak development. Using a 200-year outbreak reconstruction I determined that host susceptibility and mortality patterns had distinctly different characteristics than those described further south. Climate was more important than forest structure in determining outbreak frequency and severity, and persistent warm temperature anomalies, including the large-scale climate patterns driving these trends, were the most important direct climate drivers of outbreak development. Over short time scales, host stress preceded outbreaks, but long-term periods of vigorous tree growth were also important for outbreaks to develop. Differences between this study and others suggest that outbreak risk management and predictive models must consider regio
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2012

Title: Potential impacts of climate change in dry coastal ecosystems of British Columbia.
Contributors: Heather Klassen (author), Philip Burton (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: Climate change is impacting forest ecosystems. Climatic envelopes were developed for dry coastal ecosystems and 18 diagnostic plant species in southwestern British Columbia to project current and future suitable climate space. Future projections suggest a northward shift for ecosystem and species, with a reduction in ecosystem climate space and variable results for species climate space. Results suggest that ecosystem climatic envelopes represent cumulative biological complexity and that the ecosystem-level processes and functions cannot be allocated among the species within the plant community. A monitoring network was established to improve understanding and to detect changes in climate, soil, and vegetation relationships, and hence the distribution of ecosystems and species, over time. Baseline summaries detect climatic differences between monitored ecosystems. This climatic envelope research provides a foundation for theoretical development and the field study provides site-specific datasets to improve our understanding of forest ecosystems and our ability to manage land and resources. --P. ii.
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2012

Title: Glacier change in the Cariboo Mountains of British Columbia, Canada (1946 -- 2011).
Contributors: Matthew J. Beedle (author), Brian Menounos (Thesis advisor), Roger Wheate (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: This thesis is a five-chapter investigation of glacier change in the Cariboo Mountains of British Columbia. In chapter one I discuss the importance of glaciers, introduce the glaciers of the Cariboo Mountains, and outline the objectives and structure of this thesis. In chapter two I compare three methods to estimate annual glacier mass balance of a 9.6 km2 mountain glacier for years 2009, 2010, and 2011. I find two geodetic methods, real-time kinematic GPS (global positioning system) and photogrammetry, to provide a valuable measure of glacier-wide annual mass balance that is complementary to the glaciological method. In chapter three I reconstruct the terminus position of the same mountain glacier for the period 1959-2007 from a series of annual push moraines. Annual recession of this glacier, the longest record for a North American glacier, is controlled by air temperature during the ablation season and accumulation season precipitation during the previous decade. I demonstrate an immediate glacier terminus reaction to summer and annual mass balance and a delayed reaction to winter and annual balance. In chapter four I calculate dimensional change for 33 representative glaciers in the Cariboo Mountains for the latter half of the twentieth century. I show the period 1952-1985, when nine glaciers advanced, to be one of little net change for Cariboo Mountains glaciers. After 1985, however, rates of recession and thinning increased substantially. Comparison with climatological records reveals this marked change is due to both increased ablation season temperature and decreased accumulation season precipitation. I show glacier response to climate over this period to be highly variable and that relations between response and glacier morphometry are not consistent temporally. In chapter five I conclude this thesis with the progress gained through my research, study limitations, and the knowledge gaps that remain. Finally, I make 10 recommendations that will address knowledge gaps, and improve understanding of glacie
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2014

Title: Evaluation of climate predictability for multiple climate models at various time scales.
Contributors: Waqar Younas (author), Youmin Tang (Thesis advisor), University of Northern British Columbia (Degree granting institution)
Abstract: The predictability of the Pacific North American (PNA) pattern is evaluated on time scales from days to months using state-of-the-art dynamical multiple model ensembles including the Canadian Historical Forecast Project (HFP2) ensemble, the Development of a European Multimodel Ensemble System for Seasonal-to-Interannual prediction (DEMETER) ensemble, and the Ensemble Based Predictions of Climate Changes and their Impacts (ENSEMBLES). Some interesting findings in this study include (i) Multiple-model ensemble (MME) skill was better than skill from most of the individual models (ii) both actual prediction skill and potential predictability increased as the averaging time scale increased from days to months (iii) There is no significant difference in actual skill between coupled and uncoupled models, in contrast with the potential predictability where coupled models performed better than uncoupled models (iv) relative entropy (RE[subscript]A) is an effective measure in characterizing the potential predictability of individual predictions, whereas the mutual information (MI) is a reliable indicator of overall prediction skill (v) Compared with conventional potential predictability measures of the signal-to-noise ratio, the MI-based measures characterized more potential predictability when the ensemble spread varied over initial conditions. It is also confirmed that from monthly to seasonal time scales, the potential predictability of PNA is teleconnected with ENSO. The predictive skill on intra-seasonal time scales in the tropics is linked to Madden-Julian Oscillations (MJO). Using recently developed framework of potential predictability, information-based and ensemble based predictability measures were explored on multiple time scales for MJO predictability. Results show that there is no significant difference in the simulation of MJO in coupled (CanCM3) and uncoupled (GCM3) models. Both models simulated the tropical low frequency variability reasonably well compared with observations with some positive bias i
Discipline: Natural Resources & Environmental Studies
Content Model: info:fedora/ir:thesisCModel
Date added: 2015