Questions and Clarity: Insights from Applying Computational Methods to Paleoclimate Archives
Michaela Fendrock, Ph.D., 2022
David McGee,Co-Advisor
Alan Condron, Co-Advisor
It is a scientifically accepted fact that the Earth’s climate is presently undergoing significant
changes with the potential for immense negative impacts on human society. As evidence
of these impacts become clear and common, it becomes ever more important to constrain
the nature, magnitude, and speed of changes to Earth systems. A fundamentally important
tool to this understanding is the Earth’s past, recorded in the geologic record. There, lie
examples of climate change under various forcings: important data for understanding the
fundamental dynamics of climate change on our planet. However, when a climate signal is
written in the geologic record, it is coded into the language of proxies and distorted by time.
This thesis endeavors to decode that record using a variety of computational methods on
a number of challenging proxies, to draw more information from the climate past than has
previously been possible. First, machine learning and computer vision are used to decipher
the primary, centimeter-scale textures of carbonate deposits in Searles Valley and Mono
Lake, California. This work is able to connect facies in the tufa at Searles, grown during the
Last Glacial Period, and those forming presently at Mono Lake. Next, the tracks of icebergs
purged during Heinrich Events are simulated using the MIT General Circulation Model.
This work, running multiple experiments exploring different aspects internal and external
to the icebergs, reveals wind and sediment partitioning as centrally important to the spatial
extent of Heinrich Layers. Each of these works considers a traditional geologic archive – a
carbonate facies, a marine sediment layer – and uses computational methods to approach
that archive from a different perspective. By applying these new methods, more information
can be gleaned from the geologic record, building a richer narrative of the Earth’s climate
history. The final chapter of this thesis discusses effective teaching and strategies for building
communities to support teaching practice in Earth Science departments.