The Pacific Arctic is undergoing rapid biogeochemical changes in response to warming air temperatures caused by climate forcing. This is manifesting as changes in seasonal sea ice thickness and sea ice extent, as well as changes in primary production within surface waters. The data and samples analyzed here were collected...
In this thesis, high resolution ocean models are used to evaluate and forecast coastal ocean variability in two different applications. In the first study, the 2-km resolution ocean circulation model for the Eastern Bering Sea is utilized to understand whether slope-interior exchange along the path of the Aleutian North Slope...
Heat flow analysis of the Costa Rica convergent margin is carried out for seven core sites drilled during Integrated Ocean Drilling Program (IODP) Expeditions 334 and 344 as part of the Costa Rica Seismogenesis Project (CRISP). These expeditions were designed to develop a better understanding of erosional subduction zones. Heat...
The Eastern California Shear Zone (ECSZ) is a broad zone of dextral shear inboard of the North American - Pacific plate boundary. Despite decades of study, the significance of a mismatch between geodetic velocities and geologic fault slip rates across the ECSZ remains incompletely understood. Geodetically determined interseismic strain across...
The albedo of Arctic sea ice depends greatly on the formation of melt ponds. These ponds form in depressions on the ice as surface snow melts during the summer months, and their location is determined mainly by the initial snow topography. Using a high resolution sea ice model forced with...
The hydrologic cycle on Earth comprises the transitions among the solid, liquid, and gaseous phases of water. Understanding the hydrologic cycle is of course important for climate science, but also for agricultural, drinking water, and disaster preparedness purposes. Improvements in satellite observations and general circulation models (GCMs) have led to...
A synthesis of over 2000 paleoclimate proxy records is performed via a data assimilation framework that expands upon previous efforts by implementing a suite of physically-based proxy system models, and which provides the first example of an observationally independent, multi-seasonal (DJFM, JJAS) paleoclimate reanalysis. This methodology is contrasted against previous...
An integral component to understanding lithospheric rheology, fault mechanics, and geodynamic processes is knowledge of the subsurface thermal regime. This study presents thermal data from 26 new borehole sites drilled during the installation of borehole strain meters as part of the Plate Boundary Observatory (PBO). These data extends existing coverage...
We present a new nitrogen isotope model incorporated into the three-dimensional ocean component of a global Earth System Climate Model designed for millennial timescale simulations. The model includes prognostic tracers for the stable nitrogen isotopes, ¹⁴N and ¹⁵N, in the nitrate (NO₃ˉ), phytoplankton, zooplankton, and detritus variables of the marine...
Leads are long fractures wide enough for a ship to travel through the ice pack. Sea ice acts as a barrier between the ocean and the atmosphere, whereas leads allow the transfer of heat and moisture between the two. Leads play a role for marine mammals and are hunting grounds...