The Ozone Hole: 1985 Ozone depletion over Antarctica, first noted by British scientists, was confirmed by measurements from the Nimbus-7 Total Ozone Mapping Spectrometer (TOMS), launched in 1978. Since then, TOMS has made daily polar ozone maps of an ozone hole as large as the United States. Satellite data were invaluable in supporting the first Montreal Protocol, wherein forty nations agreed to a fifty percent reduction in the use of chlorofluorocarbons by 1999.

Chernobyl: 1986 On April 26, 1986, one of the nuclear reactors in Chernobyl, Ukraine, exploded, spewing large amounts of radioactive materials into the atmosphere. Images from US and French remote sensing satellites monitored the activity at the site. Even after the fire was out, the heat from the reactor was detected by infrared sensors in orbit. The reactor complex is the green rectangular area located just to the left of the black cooling pond. The use of remote sensing imagery to monitor emergency situations is becoming a well-established part of the field of emergency management.