Una Kim Miller

Ph.D. Candidate at LDEO | Columbia University

Ph.D., Ocean and Climate Physics, Columbia University, Expected 2022
B.S., Oceanography, University of Washington, 2015

I am a physical oceanographer interested in processes at the air-sea interface, from turbulence in the ocean mixed layer to Antarctic polynya dynamics. I work primarily with mooring data and satellite products.
You can reach me at umiller [at] ldeo.columbia.edu.

Publications

Under Review

Scaling of moored surface ocean turbulence measurements in the Southeast Pacific Ocean
Miller, U. , C. J. Zappa, S. Zippel, J. T. Farrar, R. A. Weller

In Prep

High Salinity Shelf Water production rates in the Terra Nova Bay Polynya from in-situ salinity measurements
Miller, U. , Christopher J. Zappa, Arnold L. Gordon, Seung Tae Yoon, Craig Stevens, Won Sang Lee

Peer-Reviewed

TKE Dissipation Rate Estimates from Pulse-Coherent ADCPs on Moorings .
Zippel, S, J. T. Farrar, C. J. Zappa; U. Miller , L. St. Laurent, T. Ijichi, R. A. Weller; L. McRaven; D. Le Bel. (2021).
Journal of Atmospheric and Oceanic Technology

Warming and inhibition of salinization at the ocean's surface by cyanobacteria
Wurl, O., K. Bird, M. Cunliffe, W. M. Landing, U. Miller, N. I. H. Mustaffa, et al. (2018).
Geophysical Research Letters

Analysis of bubble plume distributions to evaluate methane hydrate decomposition on the continental slope
Johnson, H. P., U. Miller, M. S. Salmi, E. A. Solomon, (2015).
Geochemistry, Geophysics, Geosystems , 16, 3825-3839.

Dissociation of Cascadia margin gas hydrates in response to contemporary ocean warming
Hautala, S. L., E. A. Solomon, H. P. Johnson, R. N. Harris, U. Miller (2014).
Geophysical Research Letters , 41, 8486-8494.

Research

High Salinity Shelf Water formation in the western Ross Sea

High Salinity Shelf Water (HSSW) is a major component of Antarctic Bottom Water (AABW), a water mass that fills the lowest kilometer of the world’s oceans and drives global thermohaline circulation. It is formed in the coastal polynyas of Antarctica, where strong offshore winds continually push away newly forming sea ice and subject the surface ocean to intensive heat loss and brine rejection. Here, we use rare mooring-based observations of active HSSW formation in the Terra Nova Bay Polynya along with on-shore meteorological measurements and satellite sea ice concentration products to estimate HSSW productions rates and characterize the processes surrouding its formation on time scales ranging from seasonal to hourly. This work is funded by a Future Investigators in NASA Earth and Space Science and Technology (FINESST) grant.


Upper Ocean Turbulence Scaling



Surface ocean turbulence is key to the transfer of heat, gas, and other important properties between the ocean and atmosphere. Turbulence can be understood through estimates of turbulence kinetic energy (TKE) dissipation rate (ε), a measure of the rate of dissipation of TKE into heat energy. Moored pulse-coherent Acoustic Doppler Current Profilers (ADCPs) represent a relatively new method of measuring ε that allows for extensive timeseries with concurrent surface flux and wave measurements. Here, we use one of the first of such datasets, collected in the surface ocean of the SE Pacific, to assess performance of various wind-, buoyancy-, and wave-based scalings of ε. A manuscript of this work is currently under review.

Outreach

I enjoy showing young people that science and coding are not just for "geniuses" or solemn-faced men clad in white lab coats. I've volunteered extensively with the Columbia University Chapter of Girls Who Code, and co-created and co-taught Pyclub, an 8-week course that aims to introduce high school students to python through the lens of oceanography.

Some fun links:
  • A Girls Who Code lesson I wrote on Python packages, featuring a bunch of gifs and pictures
  • A silly video I made on life aboard oceanographic research vessels using media that my friends and I have collected while out at sea