50 years ago, scientists puzzled over a slight global cooling
Sulfate pollution turned out to be the culprit
![smoke stacks](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2019/11/100819_CG_50YA_climate-cooling_feat.jpg?fit=1028%2C579&ssl=1)
Sulfate particles from fossil fuel burning briefly lowered global temperatures during the mid-twentieth century.
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