The following projects are seeking graduate student involvement:
Currents and waves at a glacier terminus
Retreat of marine terminating glaciers is driving global sea level rise. Energetic currents and waves at glacier termini have been identified as a possible contributor to ice melt and retreat. In collaboration with engineers at UW we are developing miniature submarine vehicles and models to study rapidly evolving flows within 500 m of a glacier terminus. This project will utilize data collected from floats and other instruments during fieldwork in Alaska, as well as numerical simulations, to characterize high-frequency waves and currents. (Jesse Cusack)
Exploring the physics of ice-melt
Theoretical predictions of glacial melt rates at marine terminating glaciers disagree with observed melt rates by over an order of magnitude. By developing new instruments that attach themselves to a melting glacier, we are exploring dynamics that lead to ice-melt of Alaska and Greenland glaciers. Exploding bubbles is an example of the type of physics we seek to explore with new sensors that measure details of glacier ice and the turbulent flows that drive melt. (Jonathan Nash, Erin Pettit, and Meagan Wengrove)
Biological aggregations at seamounts
Hundreds of underwater pinnacles in the North Pacific Ocean are believed to be hot spots of biological activity. But why? We explore how the physical and biological dynamics are related at these locations using new, detailed observations that will improve our understanding of ecology, biodiversity, and the impact on the ocean food web (Astrid Leitner, Jesse Cusack, and Jonathan Nash)
Understanding future changes in the hydrologic cycle
Climate models predict significant changes in global patterns of precipitation minus evaporation (P-E) in response to future warming. Such changes will likely have significant impacts on water resources and ocean circulation, but they are not well constrained due to large model uncertainties. This project will employ a novel method to diagnose the sources of uncertainty in projections of P-E change across several large ensembles of climate model simulations, with the goal of better understanding and constraining future hydrologic change and its impacts. (Nick Siler)
Understanding what controls water temperature in estuaries
Estuaries are biologically productive areas of the ocean that support important fisheries and coastal ecosystems. Water temperature strongly affects the biogeochemical rates and ecology of estuaries, but the dynamics that control water temperature have received little attention in comparison to the dynamics that control salinity. By synthesizing existing long time series observations of several estuaries (options include the Delaware Bay, Hudson River, Merrimack River, Columbia River, Alsea River, and others), we will determine the range of natural variability in the estuarine water temperatures and forcing. Using observations and idealized numerical model experiments, we will reveal how air-sea fluxes and river and ocean temperatures combine to determine water temperature in estuaries with various geometries and flushing times, and we will determine under what conditions temperature affects the estuarine circulation. (Melanie Fewings and James Lerczak)
Understanding oceanographic processes affecting fish recruitment, production, and distribution
One of the biggest challenges in managing fish populations is to understand how ocean and climate variability affect their distribution and abundance. In the fisheries oceanography lab we study the oceanographic processes that affect fish distribution and abundance. Much of the work that we conduct focuses on fish early life stages (eggs, larvae and juveniles) because processes occurring during fish early life are likely to influence their fate as adult, and their ability to respond and adapt to climate change. Most of our work is conducted implementing analytical approaches, such as species distribution or Lagrangian particle tracking models. Field work is common in our lab, either on annual NOAA surveys or on dedicated cruises. We conduct work in the Northeast Pacific, Gulf of Alaska, Bering Sea, North Atlantic and Mediterranean Sea. For inquiries and contacts, take a look at our lab web page.
Exploring Sea Ice Dynamics and Mechanics
The sea ice dynamics group uses field data to constrain our understanding of stress and strain relationships for pack ice, and how these vary from scales that can cover blocks of ice interaction and ice floes to representing the whole Arctic Ocean. Gaps in our knowledge exist because of the difficulty in measuring stress internally in sea ice and identifying how this varies across meters to kilometers. Field data can be used to constrain models. Currently, we are working on using the discrete element method to investigate stress-strain behavior across aggregates of ice, to use this to inform course resolution models that require internal ice stress to be homogenized over multiple ice floes or large regions. For a highly interested student, opportunities could be found to work on multiple aspects of this problem.
