Oil spills are a serious form of pollution, with the impacts extending from marine environments into people’s daily lives. Although the number of large oil spills occurring each year is declining (ITOPF), the consequences of large tanker spills are still being felt decades later.

The long-standing and widespread impacts of even one oil spill means it’s essential we still address them as a serious environmental, social and economic threat.

If we wish to reduce their impacts, the creation of response tactics and strategies need to be prioritised by maritime authorities, governments, and response organisations. Supported by this kind of proactive planning, responders have more chance of mitigating the spread of oil spills and reducing the potential impacts.

Modelling solutions can provide the intelligence necessary to create these strategies, offering rapid and advanced simulations of oil spill movements and supporting strategic decision-making that is led by data.

In this piece, we’ll discuss why oil spills can be so devastating and how modelling solutions, such as Riskaware’s MarineAware, can provide much-needed response support.

The reality of oil spills

Oil spill statistics

“ITOPF estimated that between 1970 and 2016 approximately 5.73 million tonnes of oil were lost as a result of tanker incidents” – Our World in Data

In 2018, the ITOPF recorded two large spills (greater than 700 tonnes) and three medium spills (7 to 700 tonnes) globally. – Our World in Data

3 medium spills were recorded in 2020 and the total oil spilt in the year was 1,000 tonnes. – ITOPF

A few very large spills are responsible for a high percentage of the oil spilt from 1970s to the present. – ITOPF

Up to 206 million gallons of oil were spilt during the Deepwater Horizon incident, the largest accidental spill in history. – Britannica

The world’s largest oil spill, the Persian Gulf War Oil Spill, was estimated to release between 380 and 520 million gallons of oil. – Britannica

Real-world oil spill examples

Exxon Valdez

• Date: 3 March 1989
• Location: Prince William Sound, Alaska
• Oil: Over 11 million gallons
• Impacts: Over 1,300 miles of shoreline and hundreds of thousands of wildlife affected, with total costs of around $7 billion.

Deepwater Horizon

• Date: 20 April 2010
• Location: Gulf of Mexico
• Oil: Estimated to be up to 206 million gallons
• Impacts: Leisure spend dropped by $247 million the year after and dolphins were still showing effects 10 years later.

MV Wakashio

• Date: July 2020
• Location: Pointe d’Esny, Mauritius
• Oil: More than 1,200 tonnes of fuel released
• Impacts: Over 200 miles of coastline with serious damage to coral reefs.

Amoco Cadiz

• Date: 16 March 1978
• Location: Brittany, France
• Oil: Nearly 70 million gallons
• Impacts: 200 miles of coast polluted with millions of wildlife and marine life killed.

FSO Safer

• Date: Moored 1987
• Location: Red Sea, Yemen
• Oil: Potentially 4x larger than Exxon Valdez
• Impacts: 100% of fisheries at risk, 8 million people at risk of air pollution, and total clean-up costs could reach $20 billion.

Factors influencing oil spills

Wellhead blowouts and tanker spills are two of the biggest contributors to oil in the ocean. While natural oil seepage can occur, the industrial causes of oil spills have much more capacity to cause serious and widespread impact.

The greater the amount of oil spilled, the greater the potential impact. And the longer it takes to deploy containment or clean-up efforts, the farther these impacts can spread. Natural factors can also have a large influence over the spread and resultant consequences of an oil spill.

Here are some of the primary considerations:

• Current advection
• Wind advection
• Wave advection
• Spreading (viscosity and thickness)
• Diffusion
• Evaporation
• Emulsification
• Deposition and washback
• Dispersion
• Resurfacing

Learn more about what factors influence an oil spill

The impacts of oil spills

Often, the impacts of oil spills last years. Whether indirect or direct, immediate or slow to evolve, the consequences of oil spills can be severe for people and nature.

Wildlife

Oil has detrimental impacts for marine and land life, from destroying habitats to coating animals’ skin and poisoning their food supplies.

Environment

Sensitive ecosystems are particularly at risk of disruption from oil spills, including coastlines, mangroves, and coral reefs.

Economy

Local industries, such as fisheries and agriculture or tourism, can be limited for years after an oil spill – impacting people’s livelihoods.

People

Often livelihoods of people can be affected; food production can be disrupted and people’s health may even be affected.

Related: Oil spills and the impact on the marine environment

Oil spill response

We’ve seen the way oil spills behave and move when they enter the water, and how they can be influenced by different factors. This makes determining the appropriate oil spill response strategy complex, but also essential for minimising potential impacts.

These response strategies generally need to be decided on a case-by-case basis – often in the moment of a live incident.

Who responds to an oil spill?

Making these decisions becomes even more complicated when we consider the many different groups who might be involved. Once again, the responsibility for mitigation tactics and clean-up efforts can change between events.

Here are some of the primary potential stakeholders:

• The parties who are responsible (e.g. owner of the vessel or oil rig)
• Private response companies
• Local or national coast guards
• Military, particularly naval forces
• Local communities/volunteers
• Non-government experts

Find out more about strategic oil spill response here

Common oil spill response methods

The most appropriate oil spill response method will depend on the situation, the conditions surrounding the event, and the resources responders have available.

Some other influential factors that affect response include:

• The location of the spill
• The surrounding environments present
• The geography of the area, e.g. water depth
• The sea state and other ocean conditions
• The type of oil spilled

The main aim with any response, however, is to minimise the potential impact – in order to protect environments, people, economies, and much more.

Here are some common response methods:

• Removing oil – Removing oil from a ship at risk of leaking oil has the potential to reduce or prevent any spillage.
• Booms – Booms can be placed at the site of the spill to contain the oil or protect assets by absorbing oil from the water.
• Dispersants – Dispersants are used in deep water to cause oil to sink and break up.
• Burning – In situ burning can be used to remove oil in a controlled manner.
• Mechanical recovery – Skimmers collect oil off the surface and remove it from the water.

Mitigating oil spill damage

In any oil spill response, time is the most critical resource.

The sooner oil can be contained, removed, or cleaned up, the better the chances of reducing any detrimental impacts to the surrounding environments and populations. Often, protecting key areas such as coastlines and nearby land masses will be a priority for responders, with the primary focus for resource deployment being where the impact will be most severe.

But carrying out a fast and effective response to these events is difficult. As discussed, there are a wide variety of factors which could influence the movement of an oil slick spread, with everything from oil type to sea conditions affecting how fast and in what direction oil may travel.

Understanding these factors is critical to a successful deployment strategy. And creating these strategies as far in advance as possible will help reduce the risk associated to any given spill.

Modelling tools can help fill in these data gaps. They provide intelligence that help both advanced planning and live incident response.

What is an oil dispersion model?

A dispersion model used for oil spill incidents aims to predict the movements of oil.

It uses situational data, like MetOcean forecasts and bathymetry, to account for the many factors discussed to predict how and where oil will travel. A dispersion model not only shows the movements of an oil slick, but can indicate the potential impacts on the surrounding environment. For example, it may show that a certain section of coastline is at risk of being polluted or that a critically sensitive area, like a marine reserve, might be impacted.

Learn more about incident models for oil spill incidents

Using dispersion modelling for a response

Dispersion modelling gives authorities, emergency services, and other responders in an oil spill event the situational intelligence to act effectively. With a better understanding of what areas will be affected by the oil, responders can deploy their mitigation strategies more effectively.

They can better prioritise their activities – both in terms of understanding what resources might be needed and identifying the most high-risk or sensitive areas under threat.

For example, authorities may want to prioritise their efforts to protect ecologically important locations.

The benefits:

• Helps prioritise oil spill response and resources
• Enables more targeted and informed action
• Allows responders to assess the severity of the situation
• Supports better impact and risk mitigation
• Reduces resource and clean-up costs
• Can be used for readiness planning to assess preparedness for potential future incidents

MarineAware

Riskaware’s oil spill modelling and visualisation platform, MarineAware, is a powerful tool that supports effective oil spill response, risk assessment and readiness planning.

Using robust dispersion models, MarineAware can simulate an oil spill’s trajectory based on the primary factors that influence an oil spill’s movements in the ocean. The platform uses global and local datasets to accurately simulate a wide variety of scenarios across the world.

In addition, MarineAware has the ability to perform source identification, using an algorithm developed in partnership with University of Oxford. Users can see where a spill most likely occurred in order to help identify vessels that may have been involved. This is especially useful when illegal activity is suspected.

FIND OUT MORE ABOUT OUR MARINEAWARE PLATFORM SOLUTION

Development and partnership

We have worked with multiple partners through our consultancy services to create tailored MarineAware products. MarineAware is highly agile, meaning it can be applied to a range of use cases and integrated into different systems.

Environmental Sensitivity Index (4EI)

• Identifying sensitive ecosystems or vulnerable areas
• Prioritising clean-up actions
• Understanding potential environmental risks

EASOS Marine Watch (Malaysian Government, Satellite Applications Catapult, Plymouth Marine Laboratory (PML)).

• Automatic detection of oil spills
• Remote monitoring and notification

Read more about our MarineAware collaborations

MarineAware in action

Here are some real-world examples which show how MarineAware can be used to provide essential situational awareness and to support the creation of more targeted, effective, and timely response strategies.

Mauritius

We used our MarineAware platform to assess the potential outcomes of the Mauritius oil spill.

Despite weather conditions delaying containment efforts, our modelling showed that without a response by the government, locals and international community, the outcome could have been much worse. It demonstrated that oil would have been washed up onto a much larger area of coastline, causing far greater damage to nature reserves and sensitive ecosystems.

Learn more

FSO Safer

Riskaware provided modelling support to the authorities investigating the FSO Safer risks; UK’s Foreign, Commonwealth & Development Office (FCDO). We produced predictions of the potential impacts of both air- and water-borne pollution from the vessel.

The outputs showed that an oil spill from this vessel had the potential to enact heavy contamination and pollution, extending as far as the Bab-el-Mandeb Strait, impacting the fishing economy, population health, the fuel economy, agricultural livelihoods, and much more.

Learn more

Sea Empress

We examined the Sea Empress oil spill, that occurred in South Wales in 1996. Using 4EI’s integrated ESI capabilities, we revisited this event to see how the prioritisation functionality could have reduced the impacts of a similar event today.

Learn more

Interested in learning more about MarineAware and our Marine Protection Consultancy services? Get in touch today.