Bio


My research focuses on resolving the near-surface and internal structure of the continental ice sheets in Greenland and Antarctica using airborne ice penetrating radar systems. I am particularly interested in understanding the coupling between firn structure and near-surface hydrology in Greenland, the evolution of this system in a warming climate, and its influence on the large scale ice sheet mass balance and hydrology. Additionally, I am interested in deep englacial structure as a reflection of past climate processes and ice sheet age structure. My approach to these questions involves the synthesis of electromagnetic theory, radar signal and system constraints, and in-situ observations to develop both forward and inverse methods that link physical conditions of interest within the ice sheets to their expression in radar sounding data. Applying these tools to the analysis of radar sounding data allows me to place observational constraints on state of the englacial system at scales and resolutions that bridge the gap between field measurements and numerical models. In addition, I have applied some of these same techniques to study the optimal system design parameters for future high altitude or satellite-based radar systems.

Honors & Awards


  • Best Student Poster, West Antarctic Ice Sheet Workshop (2019)
  • Best Student Oral Presentation, IGS Symposium on Five Decades of Radioglaciology (2019)
  • Fellow, National Defense Science and Engineering Graduate Fellowship (2019)
  • Steel Order of the De Fleury Medal, Army Engineer Association (2014)
  • Award for the Highest Composite Standing in Applied Science and Engineering, United States Military Academy (2012)
  • U. S. Grant Memorial Award for Excellence in Computer Science, United States Military Academy (2012)
  • Excellence in Geospatial Information Science Award, United States Military Academy (2012)

Professional Affiliations and Activities


  • Member, International Glaciological Society (2019 - Present)
  • Member, IEEE Geoscience and Remote Sensing Society (2018 - Present)
  • Member, American Geophysical Union (2018 - Present)

Education & Certifications


  • M.S., Stanford University, Electrical Engineering (2019)
  • B.S., United States Military Academy, Computer Science and Geospatial Information Science (2012)

Stanford Advisors


Lab Affiliations


Work Experience


  • Engineer Officer, United States Army (5/26/2012 - 9/1/2017)

    Location

    Joint Base Lewis-McChord, Washington, USA

  • Associate Research Analyst, Antennas and Radio Frequency Systems Division, Toyon Research Corporation (6/18/2018 - 9/15/2018)

    Location

    Santa Barbara, CA, USA

All Publications


  • Inferring Ice Fabric From Birefringence Loss in Airborne Radargrams: Application to the Eastern Shear Margin of Thwaites Glacier, West Antarctica JOURNAL OF GEOPHYSICAL RESEARCH-EARTH SURFACE Young, T. J., Schroeder, D. M., Jordan, T. M., Christoffersen, P., Tulaczyk, S. M., Culberg, R., Bienert, N. L. 2021; 126 (5)
  • Extreme melt season ice layers reduce firn permeability across Greenland. Nature communications Culberg, R., Schroeder, D. M., Chu, W. 2021; 12 (1): 2336

    Abstract

    Surface meltwater runoff dominates present-day mass loss from the Greenland Ice Sheet. In Greenland's interior, porous firn can limit runoff by retaining meltwater unless perched low-permeability horizons, such as ice slabs, develop and restrict percolation. Recent observations suggest that such horizons might develop rapidly during extreme melt seasons. Here we present radar sounding evidence that an extensive near surface melt layer formed following the extreme melt season in 2012. This layer was still present in 2017 in regions up to 700m higher in elevation and 160km further inland than known ice slabs. We find that melt layer formation is driven by local, short-timescale thermal and hydrologic processes in addition to mean climate state. These melt layers reduce vertical percolation pathways, and, under appropriate firn temperature and surface melt conditions, encourage further ice aggregation at their horizon. Therefore, the frequency of extreme melt seasons relative to the rate at which pore space and cold content regenerates above the most recent melt layer may be a key determinant of the firn's multi-year response to surface melt.

    View details for DOI 10.1038/s41467-021-22656-5

    View details for PubMedID 33879796

  • Firn Clutter Constraints on the Design and Performance of Orbital Radar Ice Sounders IEEE Transactions on Geoscience and Remote Sensing Culberg, R., Schroeder, D. M. 2020: 1-18
  • Radar-Detected Englacial Debris in the West Antarctic Ice Sheet GEOPHYSICAL RESEARCH LETTERS Winter, K., Woodward, J., Ross, N., Dunning, S. A., Hein, A. S., Westoby, M. J., Culberg, R., Marrero, S. M., Schroeder, D. M., Sugden, D. E., Siegert, M. J. 2019
  • RADAR SCATTERING IN FIRN AND ITS IMPLICATIONS FOR VHF/UHF ORBITAL ICE SOUNDING Culberg, R., Schroeder, D. M., IEEE IEEE. 2019: 4137–40