"In 1991, Landsat captured the devastating environmental consequences of war. As Iraqi forces withdrew from Kuwait, they set fire to over 650 oil wells and damaged almost 75 more, which then spewed crude oil across the desert and into the Persian Gulf. Fires burned for ten months. According to a 2009 study published in Disaster Prevention and Management, firefighting crews from ten countries, part of a response team that comprised approximately 11,450 workers from 38 countries, used familiar and also never-before-tested technologies to put out the fires. When the last one was extinguished in November, about 300 lakes of oil remained, as well as a layer of soot and oil that fell out of the sky and mixed with sand and gravel to form 'tarcrete' across 5 percent of Kuwait's landscape. An estimated one to 1.5 billion barrels of oil were released into the environment. After most burned, 25 to 40 million barrels ended up spread across the desert and 11 million barrels in the Persian Gulf, according to a 2012 paper published in Remote Sensing of Environment. For comparison, the 2010 Deepwater Horizon spill into the Gulf of Mexico is estimated to have released nearly 5 million barrels of oil. Kuwait's landscape has recovered somewhat. Clean up efforts have removed 21 million barrels of oil from the desert, but an estimated 1 million barrels still remain."