We sought to improve net ecosystem exchange (NEE) estimates for a tall, dense, mature Douglas-Fir forest in the Oregon Coast range characterized by weak flows, systematic wind directional shear, and limited turbulent mixing throughout the diurnal period. We used eddy covariance (EC) observations at two levels and concurrent biological measurements...
Leads are long fractures wide enough for a ship to travel through the ice pack. Sea ice acts as a barrier between the ocean and the atmosphere, whereas leads allow the transfer of heat and moisture between the two. Leads play a role for marine mammals and are hunting grounds...
Earth’s mantle extends to nearly 3000 km depth, comprises >80 % of Earth’s total volume, and has the largest influence on the primordial and radiogenic heat budget. Despite its importance, the structure and composition of the mantle is still debated. There are three primary models for Earth’s mantle structure that...
The focus of this dissertation is the analysis of submesoscale and finescale features measured at oceanic fronts and the role they play in the transport of heat and salt. Two different geographical areas were used to analyze this transport: one, an area on the western side of the North Atlantic...
Bedrock meandering rivers are sinuous channels that pair steep bedrock outside banks with lower gradient slip-off slopes on the inside of bends. These rivers have the potential to record information on climatic and tectonic “external” forcings in their morphology (e.g., longitudinal profiles, strath terraces, channel and valley dimensions). However, geology...
Lau Basin basalts host an array of geochemical signatures that suggest incorporation of enriched mantle source material often associated with intraplate hotspots, but the origin of these signatures remain uncertain. Geochemical signatures associated with mantle material entrained from the nearby Samoan hotspot are present in northwest Lau Basin lavas, and...
Changes in environmental conditions in marine ecosystems could directly or indirectly influence distribution, abundance, settlement, and size at settlement of flatfish. Understanding species-specific and age-specific responses to environmental variability is important for managing commercially important flatfish stocks. Slope-spawning flatfish whose offspring rely on extensive drift from the slope (spawning) to...
Magneto- and chemostratigraphic correlation underpins much of our understanding of Earth history, yet typical correlation techniques are neither quantitative nor objective. Within this dissertation, I detail my efforts to develop and apply dynamic programming-based algorithms that accomplish optimal and reproducible stratigraphic alignment. I apply these algorithms to three geologic intervals:...
Biogeochemical mechanisms employed by key organisms, or symbiotic associations of organisms, transform the function and structure of their environment through processes recognized as ecosystem engineering. This dissertation seeks to investigate organism-ecosystem interactions that serve globally significant ecological functions in marine systems and impact how systems respond to environmental change. Using...
The Toba Caldera Complex is the youngest resurgent caldera in the last 100 kyrs, formed from four overlapping eruptions starting 1.2 Myrs ago. The last caldera-forming eruption, the Youngest Toba Tuff eruption, occurred ~74 kyrs ago, emitting 2800 km3 of ash and pumice into the atmosphere and forming the caldera...