Comparing the Effect of Anthropogenically Amplified Halogen Natural Emissions on Tropospheric Ozone Chemistry Between Pre-Industrial and Present-Day

BARRERA JAVIER A.

Journal of Geophysical Research: Atmospheres

Wiley-Blackwell

Año: 2023

eactive halogens (X+XO, X= I, Br or Cl) catalytically destroy a fraction of tropospheric ozone under present-day (PD) conditions, however, their distribution and potential impact on tropospheric ozone under pre-industrial (PI) conditions remain largely unexplored. This study uses the Community Atmospheric Model with Chemistry (CAM˗Chem) to investigate the effect of anthropogenically amplified natural emissions of halogenated species and their subsequent chemistry on tropospheric ozone under PI and PD atmospheric conditions. Model results show that the global tropospheric ozone depletion due to natural halogens is slightly more sensitive in PI than PD, with percentage changes in tropospheric ozone burden (TOB) of ˗14.1±0.6% for PI and ˗12.9±0.6% for PD. Individually, the role of iodine and chlorine in ozone depletion is equivalent in both periods (ΔTOBI: ∼ ˗7% and ΔTOBCl: ∼ ˗2.5%), while bromine plays a larger role in PI (ΔTOBBr: H