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Atmospheric chemistry

The X factor

Measurements in a forest reveal a previously unknown atmospheric oxidant that acts as a source of sulphuric acid — one of the main precursors for the formation and growth of aerosol particles and clouds. See Letter p. 193

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Figure 1: Something in the air.



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Correspondence to Dwayne Heard.

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Heard, D. The X factor. Nature 488, 164–165 (2012).

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