The American professor who first discovered that the Earth's ozone layer was being dangerously depleted has died at the age of 84.
Sherwood Rowland, known as Sherry, was one of three people awarded the Nobel Prize in Chemistry for his work explaining how chlorofluorocarbons - or CFCs - could destroy the ozone layer.
The prize was given in 1995, two decades after he and a young researcher at the University of California realised the chemicals in many industrial and consumer products were depleting the Earth's ozone.
When a paper by the pair was published in the journal Nature in 1974 it was met with scorn and derision, even among scientists and especially the chemical industry, the BBC reports.
The University of California at Irvine (UCI) researcher and colleagues' calculations led in the late 1970s to some restrictions being placed on CFCs, which were then widely used as refrigerants, propellants in spray cans, solvents, and blowing agents to make foams, says the BBC.
"We have lost our finest friend and mentor," said UCI physical sciences dean Kenneth Janda. "He saved the world from a major catastrophe; never wavering in his commitment to science, truth and humanity, and did so with integrity and grace."