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A reduction in aerolized ammonium in the rural USA and increased ammonia deposition near emission hotspots

Chemical regimes of atmospheric secondary inorganic aerosol formation and nitrogen deposition in rural areas of the USA shifted from ammonia-sensitive to ammonia-insensitive between 2011 and 2020, according to analyses of long-term observations. These regime shifts led to a reduction in ammonium in aerosols and increased ammonia deposition near emission hotspots.

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Fig. 1: Sensitivities of secondary inorganic aerosol concentrations to precursor reductions between 2011 and 2020.


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This is a summary of: Pan, D. et al. Regime shift in secondary inorganic aerosol formation and nitrogen deposition in the rural United States. Nat. Geosci. (2024).

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A reduction in aerolized ammonium in the rural USA and increased ammonia deposition near emission hotspots. Nat. Geosci. 17, 594–595 (2024).

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