Stratospheric Aerosol From Above: Laser‐Ablation Mass Spectrometer Samples Polar Vortex Air for the First Time

Abstract The JGR paper by Lawler et al. (2025, https://doi.org/10.1029/2025jd043530 ) marks a significant and historic first, the PALMS single‐particle chemical analysis sampling deep stratospheric Arctic vortex air for the first time. The analysis finds ∼90% of sulfate aerosol particles in the deepest stratosphere air (100–130 ppb N 2 O) are meteoric‐sulfuric particles, their composition spectra having metal cation peaks strongly indicative of meteoric origin (see Figure 2 of Lawler et al., 2025, https://doi.org/10.1029/2025jd043530 ). Within this commentary article we note how the research aligns with findings from recent European high‐altitude aircraft field campaigns, measuring higher abundance refractory aerosol in similar deep Arctic vortex air (Curtius et al., 2005, https://doi.org/10.5194/acp‐5‐3053‐2005 ; Weigel et al., 2014, https://doi.org/10.5194/acp‐14‐12319‐2014 ). The findings also resonate historically, with SABRE‐2023 being 60 years after impactors on U‐2 high‐altitude aircraft from Australia found sub‐micron insoluble inclusions were present extensively within stratospheric sulfate aerosol (Bigg, 2012, https://doi.org/10.1111/j.1945‐5100.2012.01346.x ; Mossop, 1963, https://doi.org/10.1038/199325a0 ; Mossop, 1965, https://doi.org/10.1016/0016‐7037(65)90017‐7 ). We also summarize key related stratospheric aerosol model studies, from early conceptual and 1D stratospheric aerosol models through to today's generation of 3D interactive stratospheric aerosol composition‐climate models. Recent modeling is presented indicating that resolving meteoric smoke has a substantial thinning effect on the simulated background stratospheric aerosol layer, making sulfate particles smaller, and reducing global stratospheric mass burden.