Climate change

Crutzen and Stoermer's (2000) announcement of the Anthropocene draws attention to the agentic nature of the nonhuman world as it appears to be striking back against human intervention through an environmental crisis that is threatening humans and nonhumans alike. Their narrative reveals complex relationalities where humans are now revealed to beinseparable from the nonhuman world and both the material and discursive nature of their practices (historical, social, economic, and political) prove to be central to (re)shaping the earth, causing climate change, species extinctions as well as racism, sexism, and slavery. Rising sea levels is an important aspect of climate change that threatens major coastal places with disappearance. My dissertation offers a new approach that uses Karen Barad's (2003; 2007; 2017) agential realism and diffractive methodology to study a place called Lyme Regis – a town in west Dorset, England, threatened with disappearance as a result of rising sea levels caused by climate change – as an agential phenomenon shaped by complex multilayered material-discursive practices (political, economic, scientific, and social). Whereas current research on Barad's philosophy mainly focuses on discussions about the theory: explaining, critiquing, or defending (Gandorfer 2021; Lettow 2017; Graham 2016; Segal 2014; Geerts 2013; 2016; 2021; van der Tuin 2011; Alaimo and Hekman 2008; Rouse 2004 and more ), my project is the first ethico-political study of a place, Lyme, that applies Barad's agential realist perspective by engaging the activism of Barad's concept of "re-membering." The processual nature of the concept is particularly relevant today since its nonlinear understanding of time allows me to see how past violent material and discursive practices (racism, sexism, and slavery) at Lyme unfolds in the present troubled time of the Anthropocene. This process of re-membering that I undertake in this study involves concurrently examining the overlapping historical, economic, scientific, literary, and geological intra-acting practices through a method that Barad describes as diffractive reading. I rethink these practices in their relation to material practices and illuminate multiple layers of meaning and relationalities that constitute Lyme as an agential phenomenon, unsettling boundaries between humans and nonhumans, epistemology and ontology, material and discursive practices as well as boundaries between scientific, historical, cultural, and literary aspects of life. Therefore, within the context of the Anthropocene, chapter one rethinks how the scientific discourse (re)shapes nature and demonstrates how prioritizing the needs of human over nonhuman inhabitants in the name of saving Lyme could entail the destruction of both. Chapter two rethinks the dehumanizing and marginalizing effect of the scientific discourse by illuminating the agentic role of Mary Anning and Saartjie Baartman in the apparatus of scientific knowledge production that earned Lyme its heritage status. Finally, chapter three rethinks the entangled nature of scientific and literary practices, arguing for an agential realist account of the sublime that celebrates Lyme as a place of transformative human-nonhuman kinship based on Austen's elaborate depiction in Persuasion (1817). This reading shows science and literature as material-discursive practices operating along the unsettled boundaries between the novel and everyday life, allowing us to rethink Austen's writing as a process in constant flux.

Author Keywords: Agential Realism, Anthropocene, Diffractive Methodology, Lyme Regis, Persuasion, Posthumanist Sublime

Warming climates have had various consequences on terrestrial and aquatic food webs that are expected to persist. There is evidence suggesting that certain organisms are better equipped to handle changing climates compared to others. Therefore, the purpose of my thesis was to study the adaptability of Daphnia under temperature stress and nutrient limitation. First, to examine the effects of dietary phosphorus limitation and temperature on daphniid life-history and population growth, a series of experiments were conducted in the laboratory. In general, I found that Daphnia body growth rates and life-history traits to food carbon to phosphorus (C:P) ratios change with temperature. Next, I identified a protocol to limit the genomic DNA (gDNA) from ribonucleic acid (RNA) extractions. I found that using a modified phenol-chloroform extraction protocol was the most effective way to remove gDNA from extracted Daphnia RNA samples. Overall, results from this study show that temperature and food quality interactions are more complicated than previously thought. Furthermore, the RNA extraction protocol developed will be useful in future studies examining gene expression responses in Daphnia.

Author Keywords: ecological stoichiometry, gene expression, life-history, nutrient limitation, RNA puritiy, temperature

The "upfront" embodied carbon (EC) of building materials includes the accumulated greenhouse gas (GHG) emissions resulting from harvesting, manufacturing and transportation processes, and is becoming more widely recognized as a major source of global GHGs. The aim of this study is to demonstrate the potential for buildings to go beyond reduced or zero GHG emissions and to become– at least temporarily – a negative emissions technology, namely places of net storage of carbon. The study examines the EC for two samples of low-rise residential buildings that are representative of the North American wood-framed typology: a single-unit raised bungalow of 185m2 and an eight-unit, four-story of 935 m2. Data from Environmental Product Declarations (EPDs) for a wide variety of materials that could feasibly be used to construct the sample buildings are used to calculate the total EC for four different material assemblies in each building type: High EC, Typical EC, Best Conventional EC and Best EC. Results demonstrate the upfront embodied carbon can vary widely, ranging from a worst-case scenario of 415 kgCO2e/m2 of net emissions to a best case of 170 kgCO2e/m2 of net carbon storage by using biogenic (plant-based) materials. In addition, an energy modeling analysis of the buildings was conducted for the Toronto, Ontario climate to compare the EC with the operational carbon (OC) emissions. The results show that achievable reductions in EC could provide more than four times the overall GHG reductions than energy efficiency improvements to reduce OC between 2020 and 2050. The building model with both the lowest EC and OC is shown to have net carbon storage for several centuries. At the current scale of US residential construction, annual carbon storage in residential buildings as modeled could reach 30,000,000 tonnes, the equivalent of 10 coal-fired power plants. The immediate impact of large-scale GHG reductions from the use of carbon-storing materials is demonstrated to be worthy of consideration for the building industry and related policy makers.

Author Keywords: Biogenic carbon, Carbon accounting, Embodied carbon, Energy efficiency, Life cycle analysis, Operation emissions

This thesis proposes an agro-ecological zoning (AEZ) methodology of southern Ontario for the characterization and mapping of agro-ecological zones during the historical term (1981-2010), and their shifts into the long-term (2041-2070) projected climate period. Agro-ecological zones are homogenous areas with a unique combination of climate, soil, and landscape features that are important for crop growth. Future climate variables were derived from Earth System Models (EMSs) using a high emission climate forcing scenario from the Intergovernmental Panel on Climate Change 5th Assessment Report. The spatiotemporal shifts in agro-ecological zones with projected climate change are analyzed using the changes to the length of growing period (LGP) and crop heat units (CHU), and their manifestation in agro-climatic zones (ACZ). There are significant increases to the LGP and CHU into the long-term future. Two historical ACZs exist in the long-term future, and have decreased in area and shifted northward from their historical locations.

Author Keywords: Agro-climatic Zones, Agro-ecological Zones, Agro-ecological Zoning, Climate Change, Crop Heat Units, Length of Growing Period

Agricultural adaptation is a significant component of the larger challenge humans face in adapting to the impacts of climate change. There are extensive studies of agricultural adaptation, however little is known about how farmers in Ontario share knowledge about effective adaptation practices. This qualitative research study contributes to the understanding of the educational context within which Ontario farmers meet the demands of extreme weather on their farms. The research investigates how farmers exchange knowledge about climate change adaptation. Eight semi-structured interviews were conducted in the context of a grounded theory research approach and coded according to the systematic design. Results suggest that knowledge transfer is two-fold: farmers adapt to stresses through experimentation and engage in knowledge exchange through informal and non-institutional formal education. This study outlines the mechanisms by which adaptation and knowledge transfer occur. Implications of the research are discussed in relation to academic literature and policy.

Author Keywords: agricultural adaptation, Climate change, education, farming, grounded theory research, knowledge exchange

The breeding phenology of American Woodcocks (Scolopax minor) was evaluated in Ontario, Canada to determine if changes in dates of courtship activity have introduced negative bias into the American Woodcock Singing-ground Survey (SGS). Long-term woodcock phenology and climate data for Ontario were analysed using linear regression to determine if woodcock breeding phenology has changed between 1968 and 2014. There was no significant trend in woodcock arrival date, but arrival date was correlated with mean high temperature in March. In 2011-2013, programmable audio-recording devices (song meters) were deployed at known woodcock singing-grounds to determine if peaks in courtship activity coincided with survey dates used by the SGS. Spectrogram interpretation of recordings and data analyses using mixed-effects models indicated the SGS survey dates were still appropriate, except during the exceptionally early spring in 2012 when courtship displays were waning in one region during the survey window. The methods for interpretation of song meter recordings were validated by conducting point counts adjacent to song meters deployed at singing-grounds, and at randomly selected locations in woodcock habitat. Recommendations for the SGS protocol are included.

Author Keywords: detectability, phenology, Scolopax minor, Singing-ground Survey, song meter

Arctic terrestrial ecosystems have experienced substantial structural and compositional changes in response to warming climate in recent decades, especially the expansion of shrub species in Arctic tundra. Climatic and vegetation changes could feedback to the global climate by changing the carbon balance of Arctic tundra. The objective of this thesis was to investigate the influence of increased shrub coverage on carbon exchange processes between atmosphere and the Arctic tundra ecosystem. In this study a space-for-time substitution was used, referred to as a shrub expansion "chronosequence", with three sites along a natural gradient of deciduous shrub coverage in the Canadian low Arctic. Leaf-level photosynthetic capacity (Amax) of dominating birch shrub Betula glandulosa (Michx.) was significantly higher (P<0.05) at the site where shrubs were more abundant and taller than at the other sites. For all sites, mean Amax in 2014 was significantly lower than in 2013, in part potentially due to differences in precipitation distribution. Bulk soil respiration (RS) rate was significantly higher (P<0.05) at the site with more shrubs compared with the other sites. The differences in RS across sites appeared to be driven by differences in soil physiochemical properties, such as soil nitrogen and soil bulk density rather than soil microclimate factors (e.g. soil temperature, moisture). The three sites were either annual CO2 sources (NEP<0) to the atmosphere or CO2 neutral, with strongest annual CO2 sources (-44.1±7.0 g C m-2) at the site with most shrubs. Overall this study suggests that shrubs tundra carbon balance will change with shrub expansion and that shrub ecosystems in the Arctic currently act as annual carbon sources or neutral to the atmospheric CO2 and further shrub expansion might strengthen the CO2 emissions, causing a positive feedback to the warming climate.

Author Keywords: arctic tundra, carbon exchange, climate change, photosynthetic capacity, shrub expansion, soil respiration

Changes to the Arctic and sub-Arctic climate are becoming increasingly evident as it warms faster than other areas of the globe, supporting evidence that predictions of future warming will be amplified due to positive feedback mechanisms. The Southern Hudson Bay polar bear (Ursus maritimus) subpopulation is one of the most southerly subpopulations in the world, putting it at increased risk due to effects of climate change. Whereas many other subpopulations have been the subject of intense research and monitoring, little research has been completed detailing the movement behaviour and space use of bears within Southern Hudson Bay. I used detailed movement data collected on female polar bears to establish a baseline of movement information for this subpopulation to which future work can be compared and effects of climate change can be assessed I evaluated the use of core areas during critical periods of the year (breeding and ice breakup) and evaluated common space use as a means of assessing site fidelity during the breeding season. Movement rates and home range sizes were comparable to those of the neighbouring Western Hudson Bay subpopulation. I also found evidence of increased occurrences of long distance, late fall movements along the coast to the northwest, presumably to gain earlier access to first ice. Though space use analysis did not reveal evidence of site fidelity to specific breeding areas in Hudson Bay, I found that core use areas are at risk of substantially shortened ice duration (x¯ =76 days shorter) using projected ice data based on the high emissions A2 climate change scenario.

Author Keywords: climate change, Hudson Bay, movement, polar bear, sea ice, utilization distribution