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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited. ; The first global atmospheric model (WACCM-Al) of meteor-ablated aluminum was constructed from three components: The Whole Atmospheric Community Climate Model (WACCM6); a meteoric input function for Al derived by coupling an astronomical model of dust sources in the solar system with a chemical meteoric ablation model; and a comprehensive set of neutral, ion-molecule and photochemical reactions relevant to the chemistry of Al in the upper atmosphere. The reaction kinetics of two important reactions that control the rate at which Al+ ions are neutralized were first studied using a fast flow tube with pulsed laser ablation of an Al target, yielding k(AlO+ + CO) = (3.7 ± 1.1) × 10−10 and k(AlO+ + O) = (1.7 ± 0.7) × 10−10 cm3 molecule−1 s−1 at 294 K. The first attempt to observe AlO by lidar was made by probing the bandhead of the B2Σ+(v′ = 0) ← X2Σ+(v″ = 0) transition at λair = 484.23 nm. An upper limit for AlO of 60 cm−3 was determined, which is consistent with a night-time concentration of ∼5 cm−3 estimated from the decay of AlO following rocket-borne grenade releases. WACCM-Al predicts the following: AlO, AlOH and Al+ are the three major species above 80 km; the AlO layer at mid-latitudes peaks at 89 km with a half-width of ∼5 km, and a peak density which increases from a night-time minimum of ∼10 cm−3 to a daytime maximum of ∼60 cm−3; and that the best opportunity for observing AlO is at high latitudes during equinoctial twilight. © 2021. The Authors. ; This work was supported by Natural Environment Research Council grant NE/P001815/1. Shane M. Daly was supported by a studentship from the NERC SPHERES Doctoral Training Program. The rocket flight data was kindly provided by E. Kopp (University of Bern). The WACCM-Al and WAC-CM-Fe models were performed on the University of Leeds Advanced Research Computer (ARC4). There are no conflicts of interest for any author. ; With funding from the Spanish government through the Severo Ochoa Centre of Excellence accreditation SEV-2017-0709. ; Peer reviewed