Meteorite impacts load the atmosphere with dust and cover the Earth’s surface with debris. They have long been debated as a trigger of mass extinctions throughout Earth history. Impact winters generally last 10 years, whereas ejecta blankets persist for 103–105 years. We show that only meteorite impacts that emplaced ejecta blankets rich in K-feldspar (Kfs) correlate to Earth system crises (n = 11, p 0.000005). Kfs is a powerful ice-nucleating aerosol, yet is normally rare in atmospheric dust mineralogy. Ice nucleation plays an important part in cloud microphysics, which modulates the global albedo.
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