Other Oceanography and Atmospheric Sciences and Meteorology Commons^™

Riverine And Estuarine Co2-System Studies On The West Coast Of Florida, Christopher S. Moore

USF Tampa Graduate Theses and Dissertations

Coastal and estuarine acidification impacts ecosystem health and economic resources and has both natural and anthropogenic components (Cai et al., 2021). Riverine input is one of several important factors that can influence acidification in coastal ecosystems. Rivers disgorging into coastal environments can create strong gradients, both spatial and temporal, that make accurate CO2-system characterization challenging. The work described in this thesis provides a baseline CO2-system study of four major rivers that flow into Tampa bay with an emphasis on seasonal change. As a second objective, this thesis examines the effects of HgII additions on CO2-system measurements in organic-rich estuarine waters. …

Calibration-Free Spectrophotometric Measurements Of Carbonate Saturation States In Seawater, Erin E. Cuyler

USF Tampa Graduate Theses and Dissertations

This work describes efforts to improve methodologies and instrumentation for investigation of the marine CO₂ system. In the first section of my thesis, a method was developed that provides simple, calibration-free measurements of seawater carbonate saturation states (Ω_spec) based solely on the use of a laboratory spectrophotometer. Measurements of pH are made in paired optical cells, one with and one without added nitric acid. The amount of added nitric acid is determined through the direct proportionality between nitrate concentration and UV absorbance. After an initial calibration, the method is calibration-free and requires no volumetric or gravimetric analyses …

Field Observations And Novel Methodologies For Carbon System Assessments In Coastal Waters, Bo Yang

USF Tampa Graduate Theses and Dissertations

Coastal zones receive massive terrestrial inputs of nutrients and organic matter, and play an important role in biogeochemical cycles. The interactions of river inputs, ocean currents, atmospheric exchanges, anthropogenic influences, and biologically active ecosystems make CO₂ system studies in coastal waters highly challenging. This work focuses on improving our understanding of the CO₂ system in coastal waters through (1) development of a new methodology for measurements of CO₂ system parameters in the field; (2) observations of large spatial and temporal CO₂ system variations in coastal waters; and (3) characterization of the influence of organics on CO …

Improving Spectrophotometric Carbon System Measurements, Mark Patsavas

USF Tampa Graduate Theses and Dissertations

This work provides improved procedures for spectrophotometric carbon system measurements. Indicator dyes used for routine spectrophotometric pH measurements in seawater suffer from impurity issues, which introduce vendor-specific systematic errors in pH determinations. The magnitude of these errors for several vendors was investigated for meta Cresol Purple (mCP) and Cresol Red (CR). Flash chromatography procedures were developed to obtain purified mCP and CR on a bulk scale in order to supply the oceanographic research community with the indicators. Easy access to the purified indicators ensures global intercomparability of spectrophotometric pH determinations.

Internal consistency of marine inorganic carbon system measurements was studied …

The Spectrophotometric Analysis Of Lead Carbonate Complexation And Carbonate Saturation States In Seawater, Regina Anita Easley

USF Tampa Graduate Theses and Dissertations

The carbon dioxide (CO₂) system is the primary buffer in seawater which controls oceanic pH. Changes in the marine CO₂ system affect a number of processes such as metal speciation, mineral saturation states, auditory responses in fish, and primary productivity rates. Increased atmospheric concentrations of CO₂ from human activities (e.g. burning of fossil fuels, deforestation, and cement production) has led to a global decrease in surface ocean pH termed anthropogenic ocean acidification. One particular concern in response to increased oceanic CO₂ is a substantial decrease in the calcium carbonate (CaCO₃) saturation states, Ω …

Spatial And Temporal Variations In The Air-Sea Carbon Dioxide Fluxes Of Florida Bay, Christopher Michael Dufore

USF Tampa Graduate Theses and Dissertations

The flux of CO2 between the ocean and the atmosphere is an important measure in determining local, global, and regional, as well as short term and long term carbon budgets. In this study, air-sea CO2 fluxes measured using a floating chamber were used to examine the spatial and temporal variability of CO2 fluxes in Florida Bay. Measurements of dissolved inorganic carbon and total alkalinity obtained concurrently with chamber measurements of CO2 flux allowed calculation of ΔpCO2 from flux measurements obtained at zero wind velocity. Floating chamber measurements of ΔpCO2 were subsequently coupled with wind speed data to provide a simple …