The Weather Research and Forecast model (WRF) was utilized to study the effects of warmer lake surface temperatures on the lake effect snow (LES) environments of Lake Erie and Lake Ontario. Composites of recorded LES cases were created for WRF input to represent average LES conditions which revealed three distinct large-scale patterns. WRF runs consisted of altering lake temperatures up to 4.3°C for three future time frames. Lake Erie projections exhibited more sensitivity to alterations as more WRF runs revealed significant (p-value ≤ 0.05) changes to the environment. Lake Erie solely showed any distinctive changes with early and mid-century WRF runs with increased surface CAPE around 80 J/kg and total precipitation around 1.5 mm. Late century alterations for both lakes revealed significant (p-value ≤ 0.05) changes including up to 2.1 g/kg increased specific humidity and a 9K surface-850mb temperature difference indicating both lakes were most sensitive to late century alterations.

The cement industry represents nearly 8% of fossil fuel and industrial emissions making it a key area of focus for policymakers around the world. Much of the current effort in cement manufacturing has focused on energy efficiency and material substitution with more recent work focused on carbon dioxide uptake and recycled concrete aggregate use to address greenhouse gas emissions and material conservation, respectively. Currently, no meaningful approach exists for practitioners or policymakers to address greenhouse gas emission reduction for cement manufacturing that incorporates the concepts of material conservation. The Carbon Hierarchy is proposed as a successive stage hierarchy to address this gap. This work is logically and empirically validated using a newly constructed model incorporating the key levers of service life extension, thermal energy decarbonization, limestone substitution, mineral component (MIC), carbon dioxide uptake with consideration for the process flow that incorporated reintroduction of end-of-life (EOL) concrete as raw material or clinker substitution in cement manufacturing and as potential downstream use as aggregate. The Carbon Hierarchy proposed in this research could guide decisions to significantly reduce greenhouse gas emissions for the cement industry while ensuring material conservation. / Thesis / Doctor of Philosophy (PhD)

The scientific evidence that humans are directly influencing the Earth’s natural climate is increasingly compelling. Numerous studies suggest that climate change will lead to changes in the seasonality of surface water availability thereby increasing the need for groundwater development to offset those shortages. Research shows that the Northeast region of the U.S. is experiencing changes to its’ natural climate and hydrologic systems. This study provides the first instrumental long-term regional compilation and analysis of the water table response to the last 60 years of climate in New England. This investigation will evaluate the physical mechanisms and underlying mechanisms, natural variability and response of New England aquifers to climate variability. Using 100 long term groundwater monitoring stations with 20 or more years of data coupled with 67 stream gages, 75 precipitation stations, and 43 temperature stations, several statistical analyses are performed. Groundwater trends are calculated as normalized anomalies and analyzed with respect to regional compiled precipitation, temperature, and streamflow anomalies to understand the sensitivity of the aquifer systems to change. Trend, regression, correlation and spectral analysis are preformed on groundwater data to identify statistical relationships with climate variables, hydrogeologic properties and the hydrologic setting. Results suggest that regionally, New England aquifers respond strongly to annual and decadal changes in climate. Coherence in the relationship between groundwater and climate variables exists with a second order variability related to the hydrogeologic setting. The trend and regression analysis demonstrate that water level fluctuations are producing statistically significant results with increasing water levels over at least the past thirty years at most well sites. Long term cycles within the groundwater data suggest teleconnections with known sea surface temperature or pressure fluctuations such as ENSO, NAO, IPO and QBO. Anomalies of groundwater data within various geologic settings suggest that watershed characteristics; such as the surficial geology and topography of the region, play a role in the evolution of water levels in New England. These results have major implications for not only water management but the agriculture, forestry, fishing, and tourism industries as they all depend on the quantity and quality of water resources of the region.

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With global climates changing rapidly, animals must adapt to new environmental conditions with altered weather and phenology. Key to adapting to these new conditions is adjusting the timing of reproduction to have offspring when the conditions are best to maximize growth and survival. Using a long-term dataset on a wild population of yellow-bellied marmots (Marmota flaviventer) at the Rocky Mountain Biological Laboratory (RMBL), we investigated how the timing of reproduction changed with changing spring conditions over the past 50 years. Marmots are hibernators with a four-month active season. It is thus crucial to reproduce early enough in the season to have time to prepare for hibernation, but not too early so as snow cover prevents access to food. Importantly, climate change in this area has increased spring temperatures by 5 °C and decreased spring snowpack by 50 cm over the past 50 years. This directional change in climate may have caused adaptation. Given that adaptation to environmental conditions could arise from either microevolution or phenotypic plasticity, we evaluated how female marmots adjust the timing of their reproduction and estimated the importance of both genetic variance and plasticity in the variation in this timing. We show that, within a year, the timing of reproduction is not as tightly linked to the date a female emerges from hibernation as previously thought. We report a positive effect of spring snowpack but not of spring temperature on the timing of reproduction. There is inter-individual variation in the timing of reproduction but not in its response to changing spring conditions. Genetic variance in the timing of reproduction is low, and heritability was 8%. Earlier pup emergence date increases the number and weighted proportion of pups surviving their first winter, indicative of directional selection on this trait. The same pattern is not found for litter size with no effect of pup emergence date on the number of pups born. Further, all three of these traits are not under stabilizing selection. Taken together, it seems that we should expect some changes in this population with changing climatic conditions, but because of plasticity and not due to natural selection. Further, future studies on the marmots should not operate under the assumption that females reproduce immediately following their emergence.

No description available.

The object of this study is a program of government that has, as its immediate objective, the modification and regulation of consumer conduct deemed pertinent to climate change. Drawing from the analytical grid and conceptual tools of governmentality, this study has organized and analyzed an archive of documents related to the One-Tonne Challenge, a ‘public education’ program implemented by the Government of Canada from 2003 to 2006. There are numerous forms of conduct targeted by this program, involving many of the mundane and routine practices of everyday life. Despite their heterogeneity, the targeted forms of conduct can all be measured and evaluated according to the greenhouse gas (GHG) inventory, an ecological technology of government that has had its application extended to the ‘personal’ level. As consumers increasingly engage in practices that are energy efficient, a ‘low intensity GHG emission lifestyle’ will emerge as a new societal norm, which is declared to be the ‘ultimate strategic objective’ of the program. The analysis indentifies and describes two rationalities of government articulated within the archive of the program. Liberal principles and assumptions regarding the market economy are ascendant in practice; they delimit the range of governmental techniques that can be put into operation by the state. Nevertheless, the objectives and technologies of this program belong to an ecological rationality of government. It problematizes the liberal emphasis on ‘voluntary action’ and advances state planning of the market economy through price formation as a necessary governmental technique with which to manipulate the demand for energy and ensure that consumers become energy-efficient. The conclusion interprets and diagnoses the main dangers that could arise from the radical transformation of the market economy that would be brought about by an ecological political reason.

Lakes sediments from the Lofoten Islands, Norway, can be used to generate well resolved records of past climate and environmental change. This dissertation presents three lacustrine paleoenvironmental reconstructions that show evidence for Holocene climate changes associated with North Atlantic climate dynamics and relative sea-level variations driven by glacio-isostatic adjustment. This study also uses distal tephra deposits (cryptotephra) from Icelandic volcanic eruptions to improve the chronologies of these reconstructions and explores new approaches to crypto-tephrochronology. Past and present conditions at Vikjordvatnet, Fiskebølvatnet, and Heimerdalsvatnet were studied during four field seasons conducted from 2007–2010. Initially, each lake was characterized by measuring water column chemistry, logging annual temperature fluctuations, and conducting bathymetric and seismic surveys. Sediment cores were then collected and analyzed using multiple techniques, including: sediment density, magnetic susceptibility, loss-on-ignition, total carbon and nitrogen, δ13C and δ 15N of organic matter, and elemental compositions acquired by scanning X-ray fluorescence. Chronologies were established using radiocarbon dating and tephrochronology. A 13.8 cal ka BP record from Vikjordvatnet provides evidence for glacial activity during the Younger Dryas cold interval and exhibits trends in Ti, Fe, and organic content during the Holocene that correlate with regional millennial-scale climate trends and provide evidence for more rapid events. A 9.7 cal ka BP record from Fiskebølvatnet shows a strong signal of sediment inwashing likely driven by local geomorphic conditions, although there is evidence that increased inwashing at the onset of the Neoglacial could have been associated with increased precipitation. Heimerdalsvatnet provides a record of relative sea-level change. A 7.8 cal ka BP sedimentary record reflects changes in salinity and water column conditions as the lake was isolated and defines sea-level regression following the Tapes transgression. Cryptotephra horizons were identified in sediments of Heimerdalsvatnet, Vikjordvatnet, and Sverigedalsvatn. They were also found in a Viking-age boathouse excavated along the shore of Inner Borgpollen. These include the GA4-85, BIP-24a, SILK-N2, Askja, 860 Layer B, Hekla 1158, Hekla 1104, Vedde Ash, and Saksunarvatn tephra. This research project also explored the use of scanning XRF to locate cryptotephra in lacustrine sediments and presents experimental results of XRF scans of tephra-spiked synthetic sediment cores.

Streamflow in Western North America (WNA) has been experiencing pronounced changes in terms of volume and timing over the past century, primarily driven by natural climate variability and human-induced climate changes. This thesis advances on previous work by revealing the most recent streamflow changes in WNA using a comprehensive suite of classical hydrometric methods along with novel Deep Learning (DL) based approaches for change detection and classifica- tion. More than 500 natural streams were included in the analysis across western Canada and the United States. Trend analyses based on the Mann-Kendall test were conducted on a wide selection of classic hydrometric indicators to represent varying aspects of streamflow over 43 years from 1979 to 2021. A general geograph- ical divide at approximately 46◦N degrees latitude indicates that total streamflow is increasing to the north while declining to the south. Declining late summer flows (July–September) were also widespread across the WNA domain, coinciding with an overall reduction in precipitation. Some changing patterns are regional specific, including: 1) increased winter low flows at high latitudes; 2) earlier spring freshet in Rocky Mountains; 3) increased autumns flows in coastal Pacific North- west; and 4) dramatic drying in southwestern United States. In addition to classic hydrometrics, trend analysis was performed on Latent Features (LFs), which were extracted by Variation AutoEncoder (VAE) from raw streamflow data and are considered “machine-learned hydrometrics”. Some LFs with direct hydrological implications were closely associated with the classical hydrometric indicators such as flow quantity, seasonal distribution, timing and magnitude of freshet, and snow- to-rain transition. The changing patterns of streamflows revealed by LFs show direct agreement with the hydrometric trends. By reconstructing hydrographs from select LFs, VAE also provides a mechanism to project changes in streamflow patterns in the future. Furthermore, a parametric t-SNE method based on DL technology was developed to visualize similarity among a large number of hydro- graphs on a 2-D map. This novel method allowed fast grouping of hydrologically similar rivers based on their flow regime type and provides new opportunities for streamflow classification and regionalization. / Thesis / Doctor of Philosophy (PhD)