Project Overview

Summary:

Overview

In January 2015, Dr. Steven Murawski at the University of South Florida, College of Marine Science, was awarded an RFP-IV grant at $20,247,046 to lead the GoMRI Center for the Integrated Modeling and Analysis of Gulf Ecosystems II (C-IMAGE II) Consortium which consisted of 19 collaborative institutions and 261 research team members (including students). The primary objective of C-IMAGE-II is to advance understanding of the processes and mechanisms involved in marine blowouts and their environmental consequences. This consortium focuses both on extension of work started under the initial C-IMAGE project (part of RFP-I), along with three new initiatives: (a) field work at the IXTOC-I blowout site, (b) establishment of a marine exposure facility for fishes, and (c) a Gulf-wide assessment of fish and sediment contamination to better understand and predict oil fate and impacts of DWH and other spills.

Outreach

Over its award period (3 years, plus a 12-month no-cost extension), C-IMAGE-II organized approximately 150 outreach activities or products, including:

• C-IMAGE II provided two professional development workshop focused on (1) science communication for students, and (2) proposal writing for early-career scientists. The workshops provided hands-on experience to 26 GoMRI members taught by a professional science communicator (Julia Kumari Drapkin), and a grant writer and reviewer (Kelly Kryc). These workshops were a continuation form a C-IMAGE I workshop focused on science story telling.
• Continued community engagement programs have connected the general public, youth and families, and educators with C-IMAGE researchers and outreach products. Public events sharing research highlights and Dispatches from the Gulf 1 & 2 have engaged new audiences and continued to share findings through regular newsletters. An annual presence at the St. Petersburg Science Festival has impacted an estimated 3,000 youth and families during the C-IMAGE II project. Teacher development trainings provided hundreds of Gulf teachers with resources to incorporate C-IMAGE and GoMRI research and products into their classrooms.
• BeneathTheHorizon.org, an online oil spill timeline, compiles the variety of C-IMAGE communications resources with a new video series showing the impacts on American and Mexican coasts and the people who rely on them. Launched in 2017, the site complements the main C-IMAGE webpage and our research on the Deepwater Horizon and Ixtoc I spills.
• The Loop podcast series released five episodes during C-IMAGE II focusing on Ixtoc I research in the southern Gulf of Mexico, satellite oceanography, exposure studies at the Mote Marine Laboratory, and the 2017 OneGulf Cuba expedition.
• The StoyCollider series at the GoMOSES conferences has put the public in direct contact with researchers in a more intimate storytelling setting that personalizes science and tells the story of how and why our researchers do what they do.

Research Highlights

As of January 31, 2019, C-IMAGE-II research, which produced 40 research cruises/expeditions, resulted in 78 peer-reviewed publications, more than 350 scientific presentations and 185 datasets being submitted to the GoMRI Information and Data Cooperative (GRIIDC), which are/will be available to the public. C-IMAGE-II engaged 63 Masters and PhD students over its award period. Significant outcomes of C-IMAGE-II research are according to GoMRI Research Theme are highlighted below.

Overarching Highlights:

Since January of 2015, C-IMAGE II researchers have spent over 130 at sea throughout the Gulf of Mexico collecting environmental samples for analysis to investigate how ecosystems respond to oil contamination. What is unique about the C-IMAGE field campaign is the extent of sampling efforts, enabling a fully Gulf-Wide view. These efforts established a Gulf-wide baseline of sediment geochemistry, water properties, and fish health indicators from all four sides of the Gulf. By looking at the region in the southern Gulf impacted by the 1979 Ixtoc I spill, researchers can make predictions of the ultimate recovery of the norther Gulf after the Deepwater Horizon (DwH) spill. C-IMAGE II has collected sediment cores, pore water, surface sediment grab samples, fish and shark fin clips from every corner of the Gulf of Mexico, including across the Florida Straits. The large footprint of our sampling efforts is relevant to themes two and three as it has informed fate and transport models, in addition to quantifying ecosystem impacts.

Theme Two: Chemical evolution and biological degradation of the petroleum/ dispersant systems and subsequent interaction with coastal, open-ocean, and deep-water ecosystems. The key parameters necessary for modeling the fate and transport of oil are difficult to establish. For the DwH blowout, model parameterization is heavily reliant on the initial conditions at the wellhead, namely multifraction droplet size distributions (DSD), and the pressure and temperature differential between the reservoir and exit environment. The high-pressure facilities at the Hamburg University of Technology (TUHH), established under C-IMAGE-I and II have been continually adapted to investigate evolving DSDs based on varying initial condition setups. Moreover, the integration of methane gas into the experiments provided a more accurate representation of the plume during the DwH blowout. Results from the suite of studies suggest that “live” oil (methane-saturated crude) increased droplet volume distribution (dv50) between 74% and 97%, and significantly increased median droplet diameters. However, the DSD also becomes bimodal, with small droplets becoming more abundant in the water column. Adding these parameters into plume models and DSD estimates provides more realistic estimates of oil distribution through the water column.

The need for additional research on sub-sea dispersant injection (SSDI) inspired the development of new experiments at TUHH and associated models. The aforementioned DSDs from live oil experiments were incorporated into updated coupled models to investigate how SSDI impacts oil fate and transport. PAH concentrations from simulations with and without SSDI were compared with the BP Gulf Science database. Because of temperature- and pressure-dependent processes, the models showed that the oil dispersed naturally (due to rapidly expanding dissolved gas, pressure drop, gas hydrate formation, and hydrostatic pressure decrease) and SSDI was a secondary factor affecting DSD. Conversely, other model simulations show that SSDI application decreased the amount of PAHs that reached the surface by 24%, and resulted in a safer working environment for the first responders by decreasing the amount of VOCs by 28%. Hazardous compounds (e.g. BTEX) are soluble in water, and after SSDI, their concentrations substantially decreased in the atmosphere. Squaring these two simulations is still an area of active research in our center. Additional experiments under high pressure were undertaken at the University of Calgary to investigate how oil components differentially partition into the water column upon release, with and without dispersants. Results indicate that methane concentrations and resulting system pressures impacts the partition ratio more than the temperature changes. When dispersants are added to the deep ocean system, the amount of BTEX released into the water column increased, and that this increase was more significant near the surface.

C-IMAGE also has made substantial contributions to the study of the vertical transport of oil to the seafloor via MOSSFA. The spatial extent of the DwH MOSSFA was estimated in two regions of the northern Gulf of Mexico. Using a variety of geochemical analyses, our researchers summarized the complex transformation of hydrocarbon compounds as they are transported horizontally and vertically. Using radioisotope tracers to examine sedimentation rates, an estimated area of 12,805 to 35,425 km2 experienced MOSSFA sedimentation in 2010. An area of the DeSoto Canyon (3,075 km2) experienced MOSSFA sedimentation rates of >1.5 decays per minute (dpm) cm-2 yr-1. The heaviest accumulation (>3 dpm cm-2 yr-1) of MOS occurred northwest of the wellhead. It was also concluded that up to 14%-21% of the total oil released may have reached the seafloor.

Theme Three: Environmental effects of the petroleum/dispersant system on the sea floor, water column, coastal waters, beach sediments, wetlands, marshes, and organisms; and the science of ecosystem recovery. Perhaps the cornerstone of our theme three research lies in our Gulf wide maps of PAH associated parameters. Responding to the need for baseline data, our team assembled comprehensive maps of PAH contamination in the Gulf. The Gulf-wide database resulted in a multi-year summary of the species richness and catch-per-unit-effort (CPUE) across the Gulf of Mexico. The highest CPUE was found in the north central and northwestern Gulf, with values decreasing across the West Florida Shelf, Cuba, Yucatan Peninsula, and southwestern Gulf of Mexico, in order. Additional study on the physiological health and recovery of these fishes is ongoing; these analyses focusing on the abundance, sizes, and diversity of Gulf-wide fishes gives more context to the potential resilience and connectivity of each region to a potential oil spill.

The survey also revealed how Gulf fish differentially metabolize PAHs. Biliary PAHs in three species of offshore demersal fishes were analyzed: red snapper, golden tilefish, and king snake eel. Biliary PAH concentrations signal a short term exposure as opposed to concentrations in the liver and muscle tissues. It was found that biliary metabolite concentrations decreased in red snapper and king snake eel, while concentrations were persistently high in golden tilefish. This indicates that the exposure event was episodic as opposed to chronic, and the life histories of fish play a large role in how they manage acute exposures.

Data from the suite of exposure studies investigated the ingestion, dermal contact, and water accommodated fraction exposure vectors and improve understanding of physiological responses to oil spills. RNA transcriptome analysis of liver, testes and kidneys in the commercially important Red drum expanded the understanding of this species and contributed to national databases, NCBI-SRA. Additionally, each organ’s genomic function has been identified through this transcriptome analysis.

The Atlantis ecosystem model provides an endpoint for all field and laboratory experiments with theme 3 associated activities. Coupling the near- and far-field plume models with Atlantis was completed in 2018 and results predict a missing generation of Gulf of Mexico fishes. Modeled oil concentrations at depth provided inputs to Atlantis to estimate the exposure to fishes, especially juvenile populations. These fish would have reached maturity and entered the fishery within the next few years, but their absence could have cascading impacts through the food web, according to the model. The ecosystem model is an important tool moving forward to look at other trophic impacts of oil spills or other ecosystem perturbations.

 Proposal Abstract - C-IMAGE II