The Gulf War oil spill was one of the largest oil spills in history, resulting from the Gulf War in 1991. The apparent strategic goal was to foil a potential landing by US Marines. It also made commandeering oil reserves dangerous for US forces as visibility and movement were inhibited. The immediate reports from Baghdad said that American air strikes had caused a discharge of oil from two tankers. Coalition forces determined the main source of oil to be the Sea Island terminal in Kuwait. On January 26, three US F-117 fighter-bombers destroyed pipelines to prevent further spillage into the Persian Gulf. Several other sources of oil were found to be active: tankers and a damaged Kuwaiti oil refinery near Mina Al Ahmadi, tankers near Bubiyan Island, and Iraq's Mina Al Bakr terminal.
Early estimates on the volume spilled ranged around 11,000,000 US barrels (1,300,000 m3). These numbers were however significantly adjusted downward by later, more detailed studies, both by government (4,000,000 US barrels (480,000 m3) to 6,000,000 US barrels (720,000 m3)) and private (2,000,000 US barrels (240,000 m3) to 4,000,000 US barrels (480,000 m3)) researchers.
The slick reached a maximum size of 101 miles (160 km) by 42 miles (68 km) and was 5 inches (13 cm) thick in some areas. Despite the uncertainty surrounding the size of the spill, figures place it several times the size (by volume) of the Exxon Valdez oil spill.
The New York Times reported that a 1993 study sponsored by UNESCO, Bahrain, Iran, Iraq, Kuwait, Oman, Qatar, Saudi Arabia, the United Arab Emirates and the United States found the spill did "little long-term damage": About half the oil evaporated, 1,000,000 US barrels (120,000 m3) were recovered and 2,000,000 US barrels (240,000 m3) to 3,000,000 US barrels (360,000 m3) washed ashore, mainly in Saudi Arabia.