Tidewater glaciers drain a significant proportion of the Greenland Ice Sheet and ice masses of the Canadian Arctic and provide the primary source of icebergs in Canadian waters. However, there remains uncertainty surrounding the processes controlling ice discharge from Canadian Arctic glaciers, the drift paths of icebergs in Canadian waters, and the proximity of icebergs to shipping in the region. This thesis quantifies the processes controlling glacier dynamics from four primary glacier basins on the Prince of Wales (POW) Icefield and using a multi-year dataset of iceberg drift tracks, identifies drift patterns and proximity to ships throughout the eastern Canadian Arctic. On the POW Icefield between 2009 and 2019, Cadogan and Ekblaw glaciers underwent multiyear acceleration and deceleration limited to their lower parts, consistent with characteristics of "pulse-type" glaciers. Trinity and Wykeham glaciers underwent repeating multiyear periods of velocity acceleration between 2009 and 2019 which coincided with significant thinning at their termini. As of 2017, Trinity and Wykeham were each within ~10 m of flotation over their lowermost 4 km. These findings suggest that Trinity and Wykeham glaciers have transitioned to a flow type dominated by dynamic thinning, which is strongly influenced by subglacial topography and may be susceptible to instability of the glacier front and large-scale collapse. Given that both glaciers are grounded below sea level for ~40 km up-glacier from their termini, this process could lead to significant increases in acceleration, retreat, and solid ice discharge. Using a multi-year dataset (2011-2019) of in-situ iceberg drift locations, it was found that icebergs consistently drifted southeast along the east coast of Baffin Island, controlled by a combination of local conditions including short-term wind events, ocean surface currents and semi-diurnal tidal oscillations. A test of the assumption that icebergs drift at 2% of the wind speed indicates that this rule does not apply for the majority of icebergs in this study, which typically exceeded 2% of the wind speed, particularly at low values. The highest median iceberg drift speeds occurred during the winter and spring, reaching up to 2.3 m s⁻¹ in Nares Strait. Icebergs in this study commonly became grounded near eastern Coburg Island and along the SE coast of Baffin Island, where mean residence time exceeded 180 days in all seasons. Through an analysis of a comprehensive database of ship tracks derived from AIS (automatic identification system) data in combination with a subset of iceberg drift locations derived from in-situ satellite trackers and the Canadian Ice Island Drift, Deterioration, and Detection Database (CI2D3), areas of iceberg-ship coexistence throughout Baffin Bay were identified between 2012 and 2019. The regions that saw the largest increases in iceberg-ship coexistence were along the east coast of Baffin Island and east of Bylot Island for dry bulk vessels, and northward into Smith Sound for passenger vessels. As passenger vessels commonly have little ice strengthening, this could pose an elevated hazard to vessels operating in these regions. The results of this study provide a comprehensive examination of the factors controlling glacier terminus dynamics and stability on SE Ellesmere Island, and the drift paths of icebergs once calved. This provides insights into the life cycle of icebergs in Canadian waters, how they may change in a warming climate, and the hazards that they may pose for shipping, particularly given the rapid recent increase in ship transits across the Canadian Arctic.

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There are around 250 glaciers in Sweden, all of which are constantly changing. Knowledge about the bottom topography of glaciers can be used in many different fields and is therefore important to develop.Through ground-penetrating radar data it is possible to calculate ice thicknesses on glaciers, a method that has been used for a long time but is inefficient. At Uppsala University, the glaciology researchgroup is working on developing a new inverse method to find ice thicknesses and bottom topographyon glaciers more easily and less costly. They are testing their method on the Unna and Stour Reiddaglaciers, located in the Kebnekaise masiff just outside Kiruna. The Kebnekaise masiff are part of the Seves Nappes, which was created during the collision of the Laurentia and Baltica continents. The bedrock consists mostly of mafic rocks, but there are parts with varying resistance. This may influence the varying ice thickness. Evidence for overdeepenings in the area is believed to exist, where the glaciers themselves have created bowl-shaped depressions in the bedrock that affect how thick the ice canbecome. Lateral moraines also affect how quickly some parts of the glacier melt. To validate an inverse model method, a map based on radar measurements is needed to compare results. During the survey done in March 2024, radar measurements from the glacier was also taken.These measurements were processed by dewow filtering, normal moveout correction, depth calculations and glacier bottom marking. Based on an interpolation of the processed radar data, a map of the ice thickness of the two glaciers was made. The thickness of Unna Reidda varies from 0 to 123 meters depth and for Stour Reidda from 0 to 147 meters depth. The thickness of the glacier ice was then subtracted from the topography of the mountain to produce the bottom topographic map of the Reidda glaciers. / Det finns som kring 250 stycken glaciärer i Sverige som alla är i ständig förändring. Kunskap om glaciärers bottentopografi kan användas inom många olika fält och är därför viktig att ta fram. Genom markpenetrerande radar data är det möjligt att räkna ut is tjocklekar på glaciärer, en metod som har använts länge men som också är ineffektiv. På Uppsala universitet jobbar Forskargruppen inom glaciologi med att utveckla en ny inversmetod för att enklare och billigare ta reda på is tjocklekar samt bottentopografi på glaciärer. De prövar sin metod på Unna och Stour Reidda glaciärerna som ligger uppe i Kebnekaise-massivet strax utanför Kiruna. Kebnekaise-massivet hör till Seveskållan, som skapades under kollisionen mellan Laurentia och Baltica kontinenterna. Skållan utgörs mestadels av mafiskberggrund men det förkommer delar med varierande hårdhet. Något som eventuellt kan ha en effekt påden varierande is tjockleken. Bevis tros finnas för överfördjupning, där glaciärerna själv skapat skålformade nedbuktningar i berggrunden som påverkar hur tjock isen kan bli. Även laterala morrän påverkar hur snabbt vissa delar av glaciären smälter. För att validera inversmodells metoden behövs en karta baserad på radarmätningar för att jämföra resultat. Under insamling av data i mars 2024 togs även radarmätningar från glaciären. Dessa mätningar processades genom dewow filtrering, Normal Moveout korrektion, uträkningar av djup samt markeringav glaciärernas botten. Utifrån en interpolering av den processade radardata gjordes en karta över istjockleken av de båda glaciärerna. Unna Reidda tjocklek varierar mellan 0 till 123 meters djup och för Stour Reidda från 0 till 147 meters djup. Tjockleken på glaciärisarna drog sedan bort från fjällets topografi för att producera bottentopografisk karta över Reidda glaciärerna

Continental-scale inventories of glaciers are available, but no analogous rock glacier inventories exist. We present the Portland State University Rock Glacier Inventory (n = 10,343) for the contiguous United States, then compare it to an existing inventory of contiguous United States glaciers (n = 853), identifying geographic and climatic factors affecting the spatial distributions observed. At least one rock glacier is identified in each of the 11 westernmost states, but nearly 90% are found in just five; Colorado (n = 3889), Idaho (n = 1723), Montana (n = 1780), Utah (n = 834), and Wyoming (n = 849). Glaciers are concentrated in relatively humid mountain ranges, while rock glaciers are concentrated in relatively arid mountain ranges. Mean glacier area (0.60 ± 0.073 km2) is significantly greater than mean rock glacier area (0.10 ± 0.002 km2), though total glacier area (507.70 km2) is lower than total rock glacier area (1008.91 km2). Glacier and rock glacier areas, as a percent of small watersheds containing them, are modeled using geographically weighted regression. Glacier percent area (R2 = 0.55) is best explained by elevation range and mean fall snowfall, while rock glacier percent area (R2 = 0.42) is best explained by mean spring dewpoint temperature and slope standard deviation. Finally, we compare riparian vegetation along meltwater streams draining glaciers and rock glaciers. Initial 500 m long meltwater stream reaches emanating from a total of 35 pairs of collocated glaciers and rock glaciers were delineated, allowing estimation of riparian vegetation cover and density. Rock glacier meltwater stream riparian vegetation cover (mean cover = 86.2% ± 9.3%) and density (mean NDVI = 0.30 ± 0.02) are significantly greater (p-value < 0.05) than glacier meltwater stream riparian vegetation cover (mean cover = 64.5% ± 10.9%) and density (mean NDVI = 0.13 ± 0.01). This study shows that while the spatial distributions of glaciers and rock glaciers are both generally influenced by a combination of geographic and climatic variables, the specific forcings and local magnitudes are distinct for each cryospheric feature type, and processes inherent to rock glacier cryospheric meltwater sourcing positively influence first-order meltwater stream vegetation patterns.