University of South Florida


Deepwater Horizon: 10 Years Later Impact on the Gulf's Marine Ecosystem Persists

Top 10: University of South Florida & C-IMAGE Consortium Reveal Significant Takeaways from Deepwater Horizon Oil Disaster Research During International Conference

After nearly ten years of research, hundreds of international scientists are revealing their findings on the effects of the Deepwater Horizon (DWH) oil spill. They’re attending the final Gulf of Mexico Oil Spill and Ecosystem (GoMOSES) conference hosted by the Gulf of Mexico Research Initiative (GoMRI), an independent research program established following the British Petroleum (BP) oil spill, the largest in U.S. history. University of South Florida received one of the largest portions of the grant, totaling $36 million to establish the Center for Integrated Modeling and Analysis of Gulf Ecosystems (C-IMAGE), an international consortium of professors, post-doctoral scholars and students from 19 collaborating institutions.

Steve Murawski, PhD, director of C-IMAGE and professor of biological oceanography at the USF College of Marine Science, at the GoMOSES conference opening plenary.

As the Deepwater Horizon disaster was unfolding, USF’s College of Marine Science (CMS) organized an “all-hands-on-deck” approach to assessing the impacts of and, later, the factors that contributed to the disaster.  The goals of this research were to (1) inform the public and regulators of the short-, medium-, and long-term consequences of the disaster to the environment and people, and (2) to better understand the chain of events that lead to the spill and the consequences of response measures undertaken by the responsible parties and government responders to mitigate spill effects.  The ultimate objective of this research is to assist society in making ocean energy exploration and production safer, and to make oil spill response more effective and efficient.

Starting in 2011, USF was awarded significant grant funding totaling over $36 million by the independent Gulf of Mexico Research Initiative (GoMRI) to establish the Center for Integrated Modeling and Analysis of Gulf Ecosystems (C-IMAGE).  The 2017 portion of the grant, totaling $20.2 million was the largest non-medical grant ever awarded to USF.  C-IMAGE ultimately was comprised of 19 research institutions from throughout the USA and including institutions in Mexico, Germany, The Netherlands, Canada, Australia and Cuba.  Each of the institutions contributed their unique expertise to address critical parts of the overall research program and goals of the Consortium.

With these perspectives, 10 critical contributions made by USF and the broader C-IMAGE consortium include:

(1)   USF-CMS, under the leadership of then Dean Dr. William Hogarth, mounted the first academic research expedition devoted specifically to the Deepwater Horizon incident, using the recently acquired research vessel Weatherbird II, to assess environmental damage and identify the fates of spilled oil.  USF would go on to lead over 25 subsequent research expeditions Gulf-wide to define the temporal and spatial scope of environmental damage.  The initial expedition and research conducted in the spring of 2010 was supported by a $500 thousand contribution from the USF Foundation (recommended by then USF Senior Vice President for Research, Dr. Karen Holbrook) and a $100 thousand contract from NOAA.  In recognition of the importance of this research, then USF President Dr. Judy Genshaft supported the construction of the new Marine Environmental Chemistry Laboratory on the St. Petersburg campus. [N.B., total overhead return to the USF System from C-IMAGE has been $4.98 million],

(2)   USF & C-IMAGE (FSU, Eckerd College, UNMA in Mexico City) researchers discovered that oil contamination not only occurred widely in surface waters, but that significant quantities of crude oil were deposited at the bottom of the deep sea.  Later, C-IMAGE, along with other researchers coined the term MOSSFA (Marine Oil Snow Sedimentation & Flocculent Accumulation) to describe the mechanism responsible for significant oil accumulation on the seabed.  Results from sediment sampling also allowed assessment of the impacts and rates of recovery of benthic invertebrate communities, which have been variable.  These findings have led to the incorporation of MOSSFA in oil spill response models run by the government and USF researchers have also developed methods to predict the intensity of MOSSFA should a similar-sized oil spill occur anywhere in the Gulf of Mexico,

(3)   USF & C-IMAGE researchers (Texas A&M, Corpus Christi, UHavana, UNAM, Eckerd College, UCalgary, Penn State) developed the first comprehensive baseline of oil contamination in fishes and sediments of the Gulf of Mexico, including all the waters off the United States, Mexico and Cuba.  Researchers sampled over 15,000 fishes and took over 2,500 sediment cores to develop these baselines.  Baseline data, which were not available for fish and sediment contamination pre-Deepwater Horizon, are critical for assessing impacts from a specific spill and for calculating how quickly the ecosystem can return to its pre-spill state.  Repeated sampling of the region during 2011-2018 around the spill site has led to estimates of how quickly various species are able to detoxify oil pollution, impacts on the health of various species (e.g. “microbes to mammals”) and how fast oil stranded on the bottom has become “landfilled” there due to subsequent sediment accumulation. Importantly, no fish from yet sampled has been free of hydrocarbons, emphasizing the chronic and ongoing pollution of the Gulf,

(4)   USF and C-IMAGE researchers (Eckerd, Georgia Tech, UCalgary, FSU) returned to the site of the 1979-1980 IXTOC-1 oil well blowout off Campeche, Mexico to understand the lingering effects of that spill.  By evaluating a spill of similar size that occurred over 30 years previous to Deepwater Horizon, researchers sought to find out how persistent the effects would be over time.  The volume of the IXTOC-1 spill was about 2/3 that of Deepwater Horizon, and witnessed the first large-scale use of chemical oil dispersing agents.  Researchers discovered IXTOC-1 oil buried under about 6 cm (2-1/2 inches) of fine sediment in the deep ocean, and still visible oil was discovered in mangrove forests and along rocky shores of Campeche.  Thus, it is likely the Deepwater Horizon oil will similarly be evident in the environment 30 years and longer from now,

(5)   USF and C-IMAGE researchers (Texas A&M-Corpus Christi) reconstructed the surface oil contamination from the IXTOC-1 oil spill from then existing satellite imagery.  Using the Coastal Zone Color Scanner instrument imagery from a satellite launched in 1978, researchers were able to develop a highly accurate map of the extent of that spill, which was critical to guiding contemporary researchers to areas where oil could be found today.  USF satellite oceanographers have also developed new methods to assess and predict the extent of surface oil which will be important in any subsequent oil spill responses,

(6)   C-IMAGE researchers (Hamburg University of Technology, UCalgary and the University of Western Australia) developed the first and most realistic high-pressure testing facilities to better understand processes associated oil well blowouts in water depths of one mile and deeper.  Oil, gas and water escaping from the broken well was under extreme pressure (over 200 times sea level atmospheric pressure) and the pressure drop at the well head was sudden and substantial.  Tests conducted at the Hamburg facility conclusively demonstrated that oil was “atomized” into very small droplet particles that remained in deep water forming submerged plumes, in the absence of the use of chemical dispersants.  Work at Calgary discovered that high pressures resulted in the differential rates of partitioning of toxic substances contained in oil into seawater, increasing their toxicity to deep sea life.  Today over half of the oil from the Gulf of Mexico comes from wells over one mile deep, and the deepest are nearly two miles.  Thus, understanding the high-pressure world is key to more effective oil spill response,

(7)   C-IMAGE Researchers (Hamburg, Georgia Tech, UNAM, Calgary, Penn State) calculated effects of oil and chemical dispersants on biodegradation and bacterial community responses.  Using new genome sequencing and gene mapping tools never before applied to oil spills, researchers identified the impacts on bacterial communities in nearshore areas, including effects on species abundance, composition and gene expression.  Additionally, high-pressure experiments concluded that the rates of bacterial degradation of oil were retarded in the high pressures of the deep sea and in the presence of dispersant chemicals,

(8)   C-IMAGE researchers (USF and the University of Miami) developed comprehensive oil spill fate and effects models resulting in better accounting of the distribution, trajectories and long-term impacts of deep oil spills.  Four dimensional hydrodynamic models with oil degradation modules were used to hind-cast the effects of the Deepwater Horizon spill, and forecast the impacts of four additional spills (at various locations and times) in the Gulf of Mexico.  This represents an important oil spill scenario modeling tool to understand the relative sensitivity of oil spills in various locations.  Additionally, ecosystem models with flexible spatial scales were developed and used to hindcast the effects of Deepwater Horizon on various species (fishes, invertebrates and mammals) and a separate model calculated impacts of the IXTOC-1 spill as well,

(9)    C-IMAGE supported the education of over 230 undergraduate, graduate student, post-doctoral scholars and research associates.  Student projects were an essential part of the research conducted by USF and C-IMAGE and critical discoveries could not have been made without them.  Student experiences included participating in expedition-scale field activities to collect data, development of new, pioneering instrumentation and methods to understand various phenomena related to oil spills, presentations at prestigious scientific conferences to hone rhetorical skills and networking with eminent researchers and other early career professionals.  Graduating students have gone on to fulfilling careers in academia, government and private industries and now form the next, highly trained and motivated generation of oil spill scientists,

(10)    USF & C-IMAGE researchers summarized their major research findings in over 250 research publications and 2 books (Deep Oil Spills, and Scenarios and Responses to Future Deep Oil Spills, published in 2019-2020 by Springer Nature).  The books were authored by 155 separate authors, organized into 63 chapters addressing the issues noted above, and others.  These books conclude by making four major policy recommendations and propose additional research in 20 critical topic areas.  The policies C-IMAGE researchers believe will improve marine oil drilling safety and response include: (a) conducting site-specific risk assessments as elements of future oil drilling lease sales and approvals, (b) collecting additional broad-scale and installation-specific baseline data, (c) improving data transparency and data sharing, and (4) facilitating greater international engagement in siting, preparation, response and oil spill impact assessment.

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