Seasonal impact of biogenic very short-lived bromocarbons on lowermost stratospheric ozone between 60° N and 60° S during the 21st century

BARRERA, JAVIER ALEJANDRO; FERNANDEZ, RAFAEL PEDRO; IGLESIAS-SUAREZ, FERNANDO; CUEVAS, CARLOS ALBERTO; LAMARQUE, JEAN-FRANCOIS; SAIZ-LOPEZ, ALFONSO

ATMOSPHERIC CHEMISTRY AND PHYSICS

Copernicus Publications

Año: 2020 vol. 20 p. 8083 - 8083

1680-7316

iogenic very short-lived bromocarbons (VSLBr) currently represent ∼25 % of the total stratospheric bromine loading. Owing to their much shorter lifetime compared to anthropogenic long-lived bromine (e.g. halons) and chlorine (e.g. chlorofluorocarbons), the impact of VSLBr on ozone peaks in the lowermost stratosphere, which is a key climatic and radiative atmospheric region. Here we present a modelling study of the evolution of stratospheric ozone and its chemical loss within the tropics and at mid-latitudes during the 21st century. Two different experiments are explored: considering and neglecting the additional stratospheric injection of 5 ppt biogenic bromine naturally released from the ocean. Our analysis shows that the inclusion of VSLBr results in a realistic stratospheric bromine loading and improves the agreement between the model and satellite observations of the total ozone column (TOC) for the 1980?2015 period at mid-latitudes. We show that the overall ozon