Something Fishy in the Atlantic Night—South Atlantic Ocean

First noted in the late 1970s and early 1980s, about 200 to 300 mi (322 to 483 km) off the coast of Argentina, a city of light routinely appears in the middle of the South Atlantic Ocean as shown in the 2012 composite image (left), created with data from the VIIRS sensor on the Suomi NPP satellite. There are no human settlements there, nor fires or gas wells. But there are lots of fishing boats. Squid fishermen adorn their boats with bright lights for night fishing to draw prey into their nets. The boats cluster offshore along invisible lines: the underwater edge of the continental shelf, the nutrient-rich Malvinas Current, and the boundaries of the exclusive economic zones of Argentina and the Falkland Islands. The maps on the right show the locations of fishing boats on nine consecutive nights from April 17 to 25, 2012, also obtained with VIIRS on Suomi NPP. Note that lights appear sharper on some nights and more diffuse on others due to the presence or absence of cloud cover and fog. While not shown specifically here, other vessels are involved: In addition to the fishing boats, large refrigeration and refueling ships keep the long-distance operators working without having to go back to a port. Satellite images like these allow scientists to better understand and manage fisheries in international waters; for example, they can estimate the weekly captures of different species.

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