Marianne Cowherd

  • Program Year: 3
  • Academic Institution: University of California, Berkeley
  • Field of Study: Ecosystem Sciences
  • Academic Advisor: Manuela Girotto
  • Practicum(s):
    Pacific Northwest National Laboratory (2022)
    Lawrence Berkeley National Laboratory (2023)
  • Degree(s):
    M.S. Environmental Engineering, Stanford University, 2020; B.S. Environmental Systems Engineering, Stanford University, 2019
  • Personal URL: https://mariannecowherd.github.io

Summary of Research

Snow is a virtual reservoir that stores water during the winter and releases it at the beginning of the agricultural growing season. The structure of forests in the places where snow falls has a large impact on what happens to snow -- does it sublimate to the atmosphere, get taken up by surrounding vegetation, infiltrate into the soil, or melt and run downstream to cities and agricultural regions in the spring? Large wildfires alter forest structure in the high mountains where snow falls.

However, we do not fundamentally understand how changes to forest structure alter snow depth, density, and melt timing. Vegetation, topography, and climate have entangled impacts on energy and mass balances, and existing prediction models of forest-snow dynamics cannot be generalized to include the impacts of disturbance. While satellite observations can complement models and ground measurements, they create additional challenges in data storage and efficient analysis, which require computational advances to address.

In my work, I use remote sensing observations, computational modeling, and field data to understand spatial and temporal patterns in snow depth and density in the context of wildfire disturbance.

Publications

Girotto, M., Formetta, G., Azimi, S., Bachand, C., Cowherd, M., De Lannoy, G., ... & Massari, C. (2024). Identifying snowfall elevation patterns by assimilating satellite-based snow depth retrievals. Science of The Total Environment, 906, 167312.

Cowherd, M., Leung, L.R., and Girotto, M. Evolution of global snow drought characteristics from 1850 to 2100. Environmental Research Letters (2023). https://doi.org/10.1088/1748-9326/acd804


Cowherd, M., Egan, G., Fringer, O., and Monismith, S. Wave phase-decomposed velocity profile observations in a shallow estuary. Geophysical Research Letters (2021). https://doi.org/10.1029/2020GL092251

Egan, G.,Cowherd, M., Fringer, O., Monismith, S. Observations of near-bed shear stress in a shallow, wave- and current-driven flow. Journal of Geophysical Research: Oceans (2019). https://doi.org/10.1029/2019JC015165

Awards

University of California Berkeley:
SURF SMART graduate mentor, 2021

Stanford University:
Departmental Honors, Civil & Environmental Engineering, 2019
Undergraduate Conference Grant, 2019
Summer Undergraduate Research Fellowship, 2018