The Deepwater Horizon blowout occurred on April 20th, 2010 and released nearly 5 million barrels of crude oil into the northern Gulf of Mexico causing pollution of the water and sediment inhabited by many fishes for at least 87 days while the wellhead went uncapped. Populations of the Gulf of Mexico Red snapper, Lutjanus campechanus, an important fish to the ecology and economy in the region, exhibit affinity to shallow water oil infrastructure such as the Deepwater Horizon making them especially vulnerable to crude oil contamination. The objective of this study is to determine growth of Red snapper before, during and after the DWH spill and to assess factors potentially explaining such growth variation. Sagittal otoliths were collected from individuals sampled in 2011 - 2013 from scientific, demersal long-line surveys in the northern Gulf of Mexico (GoM) and West Florida Shelf (WFS). Age and otolith increment width analyses were performed. No annual variation in von Bertalanffy growth parameters was determined among the three catch years. The L∞ , K and t0 estimated from the complete data set (2011-2013) were 82.91, 0.20 and 0.43, respectively. However, significant differences in otolith increment width-at-age were observed in increment numbers three - seven in years following the DWH event, with declines of 13%, 15% and 22% occurring in the fourth -sixth increments. To asses the potential significance of exogenous environmental variables to observed yearly growth variation I evaluated five parameters - meridional (V) winds, zonal (U) winds, wind stress curl which is a measure of upwelling, Mississippi River discharge, and mean sea level anomaly - using a linear mixed effects model. Hypothesis testing via reduced maximum likelihood estimates indicated that variation in U winds and River discharge could significantly explain the variation in increment width. However, further work must be done in order to determine the natural, inter-annual variability in age specific growth before the results from model fitting can be considered conclusive. Mean back-calculated weight-at-age measurements were obtained in order to assess potential variation in productivity changes. Results from forward difference and reverse helmert contrast-coding indicated that weight at age three+, four+ and five+ declined by 16%, 15% and 11% in 2010, respectively. These analyses indicate a significant decline in fish growth in 2010 coincident with the DWH event, followed by a return to pre-spill rates.

The ecological effects and mechanistic efficiency of chemical oil spill countermeasures must be evaluated prior to their ethical application during real spill response scenarios. Equally important is the ability to monitor the effectiveness of any spill response in real time, permitting informed response management. In-situ sensors are key components of such event based monitoring and continuous monitoring programs. This project investigates crude oil toxicity as a particulate suspension, suitability of in-situ instrumentation to measure crude oil suspensions, and the applicability of using acoustic backscatter to measure suspended solids and sub-surface oil droplet suspension concentrations. The ecological effects to inter- and sub-tidal sediment dwelling organisms exposed to crude oil, both treated with a chemical dispersant and un-treated, was evaluated. Elevated toxicity, expressed as percent mortality and reduced luminescence, and oil concentrations were observed in inter-tidal sediments receiving oil only treatments compared to oil-plus-dispersant treatments. Sub-tidal sediments showed heterogeneous distribution of crude oil with elevated amphipod mortality compared to no oil controls suggesting an oil-sediment aggregation mechanism. A separate laboratory scale study found that the soluble crude oil fractions were responsible for the observed mortality in pelagic species while the more dominant oil droplet fractions were relatively non-toxic. Subsequent studies focused on the in-situ detection of crude oil and particle suspensions in aqueous environments. The first showed that both in-situ fluorescence spectroscopy and Laser In-Situ Scattering Transmissometry (LISST) can effectively measure crude oil concentrations in aqueous environments. The applicability of the LISST implies that crude oil in an aqueous medium can be measured as a particle suspension. Acoustic backscatter (ABS) was investigated for its applicability as a surrogate measurement technology for aqueous particle suspensions. This study showed a log linear correlation between ABS and volume concentration (VC) over a variable particle size distribution. This correlation is due to the dependency of both ABS and VC to the particle size distribution. Log-linear ABS responses to oil-droplet suspension volume concentrations were also demonstrated. However, the inability to reproduce response factors suggests that more work is required to produce viable calibrations that may be used for sub-surface oil plume detection.

A new method is presented to provide automatic sequencing of multiple hydrodynamic models and automated analysis of model forecast uncertainty. A Hydrodynamic and oil spill model Python (HyosPy) wrapper was developed to run the hydrodynamic model, link with the oil spill, and visualize results. The HyosPy wrapper completes the following steps automatically: (1) downloads wind and tide data (nowcast, forecast and historical); (2) converts data to hydrodynamic model input; (3) initializes a sequence of hydrodynamic models starting at pre-defined intervals on a multi-processor workstation. Each model starts from the latest observed data, so that the multiple models provide a range of forecast hydrodynamics with different initial and boundary conditions reflecting different forecast horizons. As a simple testbed for integration strategies and visualization on Google Earth, a Runge-Kutta 4th order (RK4) particle transport tracer routine is developed for oil spill transport. The model forecast uncertainty is estimated by the difference between forecasts in the sequenced model runs and quantified by using statistics measurements. The HyosPy integrated system with wind and tide force is demonstrated by introducing an imaginary oil spill in Corpus Christi Bay. The results show that challenges in operational oil spill modeling can be met by leveraging existing models and web-visualization methods to provide tools for emergency managers. / text

Title: Media framing of the Norilsk oil spill Author: Daria Tsymbal Supervisor: Mgr. Jan Miessler, Department of Media Studies, Institute of Communication Studies and Journalism (ICSJ) Abstract: This study examines how the Norilsk oil spill in May 2020 was framed within four factors of Situational Crisis Communication Theory (SCCT): 1. Severity of the damage; 2. Crisis responsibility; 4. Crisis history; 5. Relationship history. Also, this study examines how media ownership and closeness of the media to the government influence the framing of Norilsk Oil Spill. Using content analyses, three Russian newspapers were analyzed - Novaya Gazeta, Rossiyskaya Gazeta, and Kommersant. The results demonstrated differences in usage and frequency of frames according to media ownership and closeness to the government. Also, findings revealed that there are differences in framing concerning time frame. This thesis provides evidence that four factors in SCCT concepts (Severity of the damage, Crisis responsibility, Crisis history, Relationship history) can serve as frames in media framing analyses of crises. In addition, this study provides information for crisis managers and media professionals on how one particular crisis may be differently framed in different newspapers. Keywords: Media, crisis communication,...

Please read the abstract in the thesis. / Thesis (PhD)--University of Pretoria, 2013. / gm2014 / Paraclinical Sciences / Unrestricted

archives@tulane.edu / During the Deepwater Horizon (DWH) oil spill in 2010, approximately 0.5 billion liters (3.1 million barrels) of oil were released into the northern Gulf of Mexico during the largest marine oil spill in history . A significant portion of the released oil was weathered into residues by physical, photochemical, and biological processes prior to landing on 1773 km of coastline, including 754 km of marsh shoreline in Louisiana. Researchers endeavored to describe effects of oil residues in the soil on salt marsh organisms and communities. Many studies focused on two pillars of salt marsh ecology: the microbial communities through which a large portion of the salt marsh food web is connected and Spartina alterniflora, a foundational species of Gulf Coast salt marshes. In this dissertation I describe how cryptic, or difficult to observe, elements of salt marsh ecology, like microbial communities and plant genetics, respond to oil residues in the environment. Using a suite of field, growth chamber, and greenhouse experiments I show that these microbial communities are difficult to characterize and may respond to other factors more strongly than they do to oil residues. I present evidence that the plant is resilient to oil in the environment, and changes in its microbiome, but exerts a measurable influence on the biodegradation of oil residues and the microbiome in the soil. This dissertation provides a greater understanding of the complexity of the salt marsh response to an oil spill. / 1 / Stephen K. Formel

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Societal risks to disasters are continually increasing and the scope of policy issues surrounding emergency management in the United States remains inundated with a number of challenges. Examining the connection between social capital and political trust is paramount as prior studies have documented that if communal networks are disrupted, there will be a lasting negative impact upon the community. As such, there are specific events that cause added strain which make certain time periods for examining levels of resiliency relevant. The Deepwater Horizon oil spill that occurred on April 20, 2010, represents a large-scale, technological disaster. Not only was there a loss of human life, but a number of social and political impacts also exist with the oil having spewed out into the water. For instance, residents living along the Northern Gulf Coast do represent a heterogeneous population, which span across several geographical boundaries and represent a diverse range of cultures. Further, the economic interests of impacted residents were also likely torn between the oil and gas industry and the fishing and seafood industry, given that many individuals may have been concurrently employed full-time as oil rig workers and supplemented their financial income and/or quality of life as commercial fishermen. The goal of this research is to investigate how social capital and political trust significantly affect communal resiliency among those impacted by the oil spill. Results from this study will extend the limited understanding on the role of disaster responsibility in emergency management. Findings reveal that group belonging as related to race, education, and income significantly impact quality of life and trust in government which, in turn, influences the perception of disaster responsibility. Specifically, when trust goes down, a higher percentage of respondents indicate that the victims themselves should assume the majority of responsibility for taking care of themselves and their families following a disaster. Perhaps, individuals who are the least trusting or most cynical of the federal government feel that victims are better off taking care of themselves and their families in the aftermath of disaster given the storied history of disaster response.

The goal of this research is to understand the impacts of the 2010 Deepwater Horizon oil spill and the 1970-1980 IXTOC-I oil spill and other anthropogenic activity (e.g. dam construction) on surface water primary productivity by measuring sedimentary biogenic silica. It is known that sedimentary biogenic silica is distinct from mineral – bound silica, therefore it has been used as a proxy record for surface water primary productivity (e.g. diatom blooms). The Deepwater Horizon oil spill resulted in a widespread Marine Oil Snow Sedimentation and Flocculent Accumulation (MOSSFA) event. The IXTOC-I oil spill was one of the largest oil spills in history and it is likely that the MOSSFA event occurred as a direct result. MOSSFA is characterized by increased deposition of surface derived components and dramatic changes in post-depositional chemical (redox) and biological (benthic meio- and macro-fauna) conditions. Sedimentary biogenic silica provides an independent record of the surface derived portion of MOSSFA inputs. Occurrences of MOSSFA after IXTOC-I and Deepwater Horizon were compared by collecting sediment cores from the northern Gulf of Mexico (Deepwater Horizon) and the southern Gulf of Mexico (IXTOC-I). An age model for each core was developed using short-lived radioisotopes (i.e. 210Pbxs). Sedimentary biogenic silica was significantly elevated in sedimentary intervals affected by the Deepwater Horizon spill. This suggests that a significant portion of the surface biological materials entrained during the MOSSFA event were sourced by diatom production. However, only one core (of three from the oil spill influenced area utilized in this study) from shallower depth had elevated levels of sedimentary biogenic silica in the sedimentary interval associated with IXTOC-I. Also, the down-core profiles of sedimentary biogenic silica from the other cores collected in the southern Gulf of Mexico are consistent with the history of dam construction (1949 to 1989) on the Grijalva and Papaloapan river systems. These two river systems are the dominant freshwater and nutrient sources for primary production in the Bay of Campeche region in the southern Gulf of Mexico and therefore the dominant control on diatom productivity and sedimentary biogenic silica distribution. Consequently, distribution of annual fresh water outflow and nutrient supply has transitioned from seasonal (before 1940’s) to stable (after 1980’s). Overall, sedimentary biogenic silica provides an independent record of surface derived MOSSFA inputs and serves as a proxy for other anthropogenic influences related to surface primary productivity variability.