| Summary: | 2016 Fall. Includes bibliographical references. During the past decade, there has been rapidly growing interest in using the naturally occurring seismic noise field to study oceanic, atmospheric, and surface processes. As many seismic noise sources, are non-impulsive and vary over a broad range of time scales (e.g., minutes to decades), they are commonly analyzed using spectral analysis or other hybrid time-frequency domain methods. The PQLX community data analysis program, and the recently released Noise Tool Kit that I co-developed with Incorporated Research Institutions for Seismology’s Data Management Center are used here to characterize seismic noise for a variety of environmental targets across a broad range of frequencies. The first two chapters of the dissertation place a strong emphasis on analysis of environmental microseism signals, which occur between 1-25 s period and are dominated by seismic surface waves excited by multiple ocean-solid Earth energy transfer processes. I move away from microseisms in Chapter 3 to investigate the generally higher frequency seismic signals (> 0.33 Hz) generated by fluvial systems. In Chapter 1, I analyze recently collected, broadband data from temporary and permanent Antarctic stations to quantitatively assess background seismic noise levels across the continent between 2007-2012, including substantial previously unsampled sections of the Antarctic continental interior. I characterize three-component noise levels between 0.15-150 s using moving window probability density function-derived metrics and analyze seismic noise levels in multiple frequency bands to examine different noise sources. These metrics reveal and quantify patterns of significant seasonal and geographic noise variations across the continent, including the strong effects of seasonal sea ice variation on the microseism, at a new level of resolution. Thorough analysis of the seismic noise environment and its relation to instrumentation and siting techniques in the Polar Regions facilitates new ...
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