EGU General Assembly 2023
© Author(s) 2023. This work is distributed under
the Creative Commons Attribution 4.0 License.

Very short-lived halogens amplify recent and future ozone depletion trends in the tropical lower stratosphere.

Julián Villamayor1, Fernando Iglesias-Suarez2, Carlos A. Cuevas1, Rafael P. Fernandez3, Qinyi Li1, Marta Abalos4, Ryan Hossaini5, Martyn P. Chipperfield6,7, Douglas E. Kinnison8, Simone Tilmes8, Jean-François Lamarque8, and Alfonso Saiz-Lopez1
Julián Villamayor et al.
  • 1Institute of Physical Chemistry Rocasolano, CSIC, Atmospheric Chemistry and Climate, Madrid, Spain (
  • 2Deutsches Zentrum für Luft- und Raumfahrt (DLR), Institut für Physik der Atmosphäre, Oberpfaffenhofen, Germany
  • 3Institute for Interdisciplinary Science (ICB), National Research Council (CONICET), FCEN-UNCuyo, Mendoza, Argentina
  • 4Earth Physics and Astrophysics Dep., Universidad Complutense de Madrid, Madrid, Spain
  • 5Lancaster Environment Centre, Lancaster University, Lancaster, UK
  • 6School of Earth and Environment, University of Leeds, Leeds, UK
  • 7National Centre for Earth Observation, University of Leeds, Leeds, UK
  • 8Atmospheric Chemistry Observations and Modelling, NCAR, Boulder, CO, USA

Recent observational evidences show ongoing net ozone depletion in the tropical lower stratosphere (LS) since the late 20th century, in contrast to the overall stratospheric ozone recovery following controls in the Montreal Protocol to limit the production of long-lived ozone depleting substances. Such behavior is currently thought to be driven by dynamical transport accelerated by global warming. In contrast, the role of chemistry, i.e., the enhanced ozone depletion due to emissions of halogenated ozone-depleting very short-lived substances (VSLS) has been considered to be unimportant. Here we employ a chemistry-climate model with a comprehensive chemical scheme to demonstrate that VSLS chemistry accounts for around a quarter of the observed tropical LS negative ozone trend in 1998-2018. We attribute such an effect to chemical reactions with VSLS from natural and anthropogenic emissions in concert. Future projections show the persistence of the currently unaccounted for contribution of VSLS to ozone loss throughout the 21st century in the tropical LS, the only region of the global stratosphere not projecting an ozone recovery by 2100. Our results show evidence for the need of mitigation strategies for regulating anthropogenic VSLS emissions to preserve the present and future ozone layer in low latitudes.

How to cite: Villamayor, J., Iglesias-Suarez, F., Cuevas, C. A., Fernandez, R. P., Li, Q., Abalos, M., Hossaini, R., Chipperfield, M. P., Kinnison, D. E., Tilmes, S., Lamarque, J.-F., and Saiz-Lopez, A.: Very short-lived halogens amplify recent and future ozone depletion trends in the tropical lower stratosphere., EGU General Assembly 2023, Vienna, Austria, 24–28 Apr 2023, EGU23-11571,, 2023.