Environmental Internship Program - 2023 Booklet

OCEANS AND
ATMOSPHERE
Hugh Shields ’24
GEOSCIENCES
Certificates: Applied and Computational
Mathematics, Statistics and Machine Learning
PROJECT TITLE
SubZero: Discrete Element
Sea Ice Modeling
ORGANIZATION(S)
School of Oceanography,
University of Washington
LOCATION(S)
Seattle, Washington
MENTOR(S)
Georgy Manucharyan,
Assistant Professor,
School of Oceanography,
University of Washington;
Brandon Montemuro,
Postdoctoral Scholar,
School of Oceanography,
University of Washington
My research focused on pancake ice, a type of
sea ice composed of rounded floes. Pancake ice
is found in the Southern Ocean and has begun
appearing more frequently in the Arctic due
to climate change. The scale of pancake ice
formation is too small to be resolved in today’s
global climate models, and the processes
that drive pancake ice formation are poorly
understood. As pancake ice becomes more
common, understanding its formation will be
useful for naval navigation of an increasingly
ice-free Arctic and will also help resolve oceanatmosphere
couplings in climate models. I
worked to reproduce pancake ice in SubZero, a
sea ice model that represents chunks of ice as
an interacting set of polygons constrained by
physical laws, that can fracture, weld together
and interact with topography. Specifically, I
developed code to represent wavefields in the
model, improving corner fracturing of floes at
a small scale, and building in the capability for
wave curvature-induced fractures, which are
necessary processes for pancake ice formation.
Working with SubZero gave me insight into
the computational challenges of working with
a complex discrete element model and the
difficulties of modeling processes that are hard to
observe.
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