Atmos. Meas. Tech., 14, 4737–4753, 2021 https://doi.org/10.5194/amt-14-4737-2021 © Author(s) 2021. This work is distributed under the Creative Commons Attribution 4.0 License. On the capability of the future ALTIUS ultraviolet–visible–near-infrared limb sounder to constrain modelled stratospheric ozone Quentin Errera, Emmanuel Dekemper, Noel Baker, Jonas Debosscher, Philippe Demoulin, Nina Mateshvili, Didier Pieroux, Filip Vanhellemont, and Didier Fussen Royal Belgian Institute for Space Aeronomy (BIRA-IASB), Brussels, Belgium Correspondence: Quentin Errera (
[email protected]) Received: 22 December 2020 – Discussion started: 21 January 2021 Revised: 7 May 2021 – Accepted: 27 May 2021 – Published: 29 June 2021 Abstract. ALTIUS (Atmospheric Limb Tracker for the In- 1 Introduction vestigation of the Upcoming Stratosphere) is the upcoming stratospheric ozone monitoring limb sounder from ESA’s Stratospheric ozone (O3) is an essential component of the Earth Watch programme. Measuring in the ultraviolet– Earth’s system. By absorbing solar ultraviolet (UV) light in visible–near-infrared (UV–VIS–NIR) spectral regions, AL- the stratosphere, it protects the Earth’s surface from expo- TIUS will retrieve vertical profiles of ozone, aerosol extinc- sure to harmful radiation (Brasseur and Solomon, 2005). Sur- tion coefficients, nitrogen dioxide and other trace gases from face emissions of halogen compounds, whose production has the upper troposphere to the mesosphere. In order to maxi- been progressively banned after the implementation of the mize the geographical coverage, the instrument will observe Montreal Protocol in 1987, are responsible for the reduction limb-scattered solar light during daytime (i.e. bright limb of the ozone layer worldwide (WMO, 2018).