The 2010 Deepwater Horizon oil spill, commonly known as the BP oil spill, was one of the worst environmental disasters of the last 20 years. The Deepwater Horizon oil rig famously exploded and began to leak on the 20th of April, and the well wasn’t fully sealed until the 19th of September that year, resulting in the discharge of 780,000m3 of oil, the loss of 11 lives and untold damage to the local ecosystem in the Gulf of Mexico.

Until now, it wasn’t fully known what long-term effect the spill would have on the 8,000+ species which call the Gulf their home. Gulf coral communities were lost in less than 6 months, with further research definitively linking the spill with this loss of diversity. In 2011 dead baby dolphins washed up on the shore in their hundreds, with many captured and tagged dolphins showing signs of ill health.

It is without a doubt that the spill had a drastic effect on the short-term prosperity of this ecosystem, but what long- term effects could be emanating from this disaster? A paper by leading researchers at Pennsylvania State University has shown that the long-term effects of the spill on Gulf communities of coral is ‘deeper and broader than expected’.

Corals are often used as a tracking species for natural disasters such as mass extinctions, as they are very sensitive to environmental changes. The way in which a coral grows, outwards, is achieved by producing sequential layers. Each layer leaves a fingerprint, unique to the conditions of the sea when it was produced, leaving a history of the sea while it was alive, and making it a perfect tool for analysis of past events such as the Deepwater Horizon oil spill.

Despite coral sites being scarce throughout Gulf ecosystems, the researchers in this team have managed to discover several applicable locations, and analysed them in order to prove that the spill had drastic effects on corals living as deep as 1,800m, and those as far away from the edge of the spill site as 14km.

Sentry vehicles towed behind a manned boat teamed up with a hi-tech seismic reader to identify the possible sites of the coral, before a remote control vehicle with an ultra sensitive camera was finally sent in to gather data from the sites. Charles Fisher, who led the team in their endeavours, said ‘we were able to collect beautiful, high-resolution images of the coral’. These images were then compared with data taken from 2010 coral sites, which were known to have significant oil damage.

The shocking results obtained from this study show that we still do not truly understand the extent to which major events such as this one are affecting the environment. The short-term effects are proving to be only the tip of the iceberg in this case, and possibly many others. Charges have been handed out to several directing members of BP in the case of this accident, and it is possible that punishments could be more severe in the future, with the results of this study taken into consideration.

It is also important to note that BP now has fully apologised and taken responsibility for the accident, and runs an ongoing program at which is helping to restore the environment in the Gulf of Mexico following the Deepwater Horizon’s accident, and has funds in excess of $28 billion dedicated to the cause.