Oil is an essential part of modern life. Without this precious fuel, cars and lorries would stay off the road, planes would be unable to fly and many industries would grind to a halt. Yet oil can also be a threat to Nature if it is not handled properly. Oil spills can spread across huge areas of ocean. The brown slicks coat everything they touch with clinging slime, killing many birds and sea life, and covering sandy beaches or coral reefs.
The latest catastrophe involving oil began on 22 April 2010, after a drilling rig exploded and sank in the Gulf of Mexico. Since then, millions of barrels of crude oil have escaped from a damaged oil well on the sea bed, threatening a major environmental disaster.
The spread of the brown monster has been monitored by many satellites, including ESA’s Envisat. These ‘eyes in space’ provide essential, up-to-date, information for thousands of government officials and many more people who make their livings from fishing and tourism.
Optical instruments on the spacecraft detect the slick during the day, when the area is cloud-free. Radar instruments can see the oily blanket at night and under cloud. By providing information about the ocean waves and currents, it is also possible to calculate how the pollution may spread.
The images show that the oil has become trapped in a circular current, keeping it – at least for the moment – well away from most of Florida. Meanwhile, the hurricane season has begun, and satellites are looking out for powerful storms that will delay efforts to permanently plug the leak.
