How many times a year do ships sink?

The numbers given for the count of ships that sink in a year are slightly different depending on the source. It has often been claimed that "severe weather has sunk more than 200 supertankers and container ships exceeding 200 metres in length during the last two decades", and that rogue waves are believed to be the major cause in many such cases. That claim was made by the MaxWave project in 2001 (without any evidence) and was repeated in a press release by the European Space Agency in 2004. But that rogue waves were the cause is not consistent with other reports and available statistics.

According to the casualty statistics held by Lloyd's Register (which documents the career of every ship in the world), only 142 vessels of that size (of any type, not just tankers and container ships) were lost during the two decades to 2001. The losses were mostly due to the usual causes: fire, collisions, groundings and structural failure, plus losses due to military action during the Iran-Iraq war. None were attributed to rogue waves.

Tim Roxby of Lloyd's Marine Intelligence Unit in England said that "an average of four ships sink every week", and in 2003, 211 vessels disappeared, 24 of them more than 100 meters long.