Curriculum Vitae

Arctic internal waves

Sea ice over the Chukchi Sea.

Sea ice over the Chukchi Sea.

Arctic internal waves are relatively weak due to damping and insulation from atmospheric forcing by sea ice. In response to recent ice loss, internal wave generation in the Arctic may increase. My research aims to understand how changes in the extent and strength of the ice pack affects the internal wave field, and using this information attempt to predict where the greatest change will occur.

Biophysical interactions in the Chukchi Sea

Copepod with egg clutch.

Copepod with egg clutch.

The shallow Chukchi Sea is an incredibly dynamic system, with large changes in water mass composition and stratification that are caused by the annual ice growth and melt. It is also a highly productive ecosystem, fueled by nutrient rich Pacific water that flows northward into the Arctic. I am exploring how physical processes, such as water mass variability and internal wave induced mixing, control phytoplankton abundance and diversity in this marginal Arctic Sea.

Western boundary waves

Not much is known about the long-term variability of tidal and wind generated internal waves due to the lack of long-term data. Are there distinct seasonal, inter-annual and even fortnightly cycles? Or are they unpredictable due to other environmental changes?  Along with my collaborator Zoltan Szuts (UW), we are trying to answer some of these questions, using over 6 years of data from the RAPID array deployed at 26 N in the Atlantic Ocean. 

NSF Award #1356383 

Sea ice deformation

Tracks of over 700 drifters deployed in the Arctic from 2000-2010.

Tracks of over 700 drifters deployed in the Arctic from 2000-2010.

In the last 10 years, there has been a drastic decrease in Arctic sea ice thickness and extent. By utilizing satellite-tracked drifter data from the International Arctic Buoy Project to calculate ice divergence and shear-strain rates, Jennifer Hutchings (OSU) and I examining the how the strength of Arctic ice pack changing. This work will also result in a new high-resolution data set of buoy trajectories that will be made available to the public.

Acrobat towed instrument platform

Sea Science's Acrobat Towed Instrument Platform.

Sea Science's Acrobat Towed Instrument Platform.

Sea Science's Acrobat is a towed instrument platform which is able to make high-resolution observations of the upper ocean structure. While working at the University of Alaska, Fairbanks I designed and created an advanced data acquisition and processing system for the platform. This included a real-time data display, which is the most advanced created for this platform to date. 

Internal waves at ocean boundaries

Bathymetric relief of the Oregon Continental Slope.

Bathymetric relief of the Oregon Continental Slope.

The bulk of tidal energy energy converted to internal waves propagates away from their generation region. Eventually these internal tides shoal onto abrupt topography such as continental slopes. Using data from a moored array placed across the Oregon continental slope, we showed that once they shoaled, the internal waves broke on the continental slope creating huge, turbulent upslope bores, similar to wave breaking at a beach. 

Standing internal waves

The currents and vertical displacements caused by the passage of a single internal wave is easily described by a known set of equations. However, a random location in the ocean is rarely comprised of just a single wave. Instead it is often populated by a multi-directional wavefield, creating complex standing wave patterns which can be easily misinterpreted. I use internal wave dispersion and polarization relations to derive a set of characteristic equations for superposed waves, so that uni-directional wavefields can be distinguished from multi-directional ones and the direction of internal wave propagation can be determined.