According to satellite monitoring environmental group SkyTruth, an oil slick about 150 miles long in the Red Sea is believed to have been released by a merchant ship.
The discharge was first discovered off the coast of Sudan by Sentinel-2 satellite imagery on May 19, 2023.
SkyTruth reports that the oil slick is approximately 250km long and was likely ejected from a moving ship over the course of several hours. The company said the spilled volume was at least 120,000 gallons, but could be much more depending on the thickness of the oil at the surface.
“The unusually large size and volume of this oil slick suggests it may be the result of tank cleaning by a petrochemical tanker and not the bilge discharge of a cargo ship,” SkyTruth said a twitter thread his previous knowledge.
The company used AIS data to narrow down possible culprits. Three vessels were identified as suspects: a Vietnamese-flagged tanker, a Panama-flagged container vessel, a Marshall Islands-flagged bulk carrier and a Bahamas-flagged bulk carrier.
SkyTruth added that the polluting vessel was not “walking in the dark,” meaning it was transmitting AIS at the time of publication.
Oil discharges from ships are regulated by the IMO’s International Convention for the Prevention of Pollution from Ships (MARPOL), specifically MARPOL Annex I, which deals with the prevention of oil pollution.