Year of Award


Document Type


Degree Type

Doctor of Philosophy (PhD)

Degree Name


Department or School/College

Department of Chemistry and Biochemistry

Committee Chair

Christopher Palmer

Commitee Members

Michael DeGrandpre, Klara Briknarova, Burke Hales, Garon Smith


University of Montana


Submersible Autonomous Moored Instruments for pH and pCO2 (SAMI-pH and SAMI-CO2) were deployed in a coastal upwelling zone on the Oregon Coast to collect unique multi-season, multi-year datasets of carbonate system dynamics. This is the first long-term deployment of the SAMI-pH paired with a SAMI-CO2. The objectives of this study included (1) improving the accuracy of the SAMI-pH (2) assessing the performance of using paired SAMI-pH and SAMI-CO2 measurements to calculate other carbonate system parameters and (3) analyzing the data to better understand the seasonal, inter-annual, and upwelling variation in the coastal marine carbonate system. SAMI-pH accuracy was improved by better characterization of the pH indicator used in these spectrophotometric measurements. Using paired SAMI-pH and SAMI-CO2 measurements from this study to calculate calcium carbonate saturation states (Ω) occasionally induced significant offsets in the results and so should be used with caution. However, a salinity-derived alkalinity for the region was found to calculate more accurate Ω when paired with either SAMI-pH or SAMI-CO2 measurements. This unique, long-term, high temporal resolution dataset (collected over a period of five years) was used to characterize the carbonate system dynamics in this coastal upwelling zone. Large, fast changes in Ω (>3.0) occurred over a period of a few days and aragonite saturation state (ΩAr) decreased to undersaturation (ΩAr



© Copyright 2013 Katherine Elizabeth Harris