Global ozone depletion and increase of UV radiation caused by pre-industrial tropical volcanic eruptions

Large explosive tropical volcanic eruptions inject high amounts of gases into the stratosphere, where they disperse globally through the large-scale meridional circulation. There is now increasing observational evidence that volcanic halogens can reach the upper troposphere and lower stratosphere. H...

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Bibliographic Details
Published in:Scientific Reports
Main Authors: Brenna, Hans, Kutterolf, Steffen, Krüger, Kirstin
Format: Article in Journal/Newspaper
Language:English
Published: Nature Research 2019
Subjects:
Online Access:https://oceanrep.geomar.de/id/eprint/47182/
https://oceanrep.geomar.de/id/eprint/47182/1/s41598-019-46253-1.pdf
https://oceanrep.geomar.de/id/eprint/47182/2/s41598-019-45630-0.pdf
https://doi.org/10.1038/s41598-019-45630-0
Description
Summary:Large explosive tropical volcanic eruptions inject high amounts of gases into the stratosphere, where they disperse globally through the large-scale meridional circulation. There is now increasing observational evidence that volcanic halogens can reach the upper troposphere and lower stratosphere. Here, we present the first study that combines measurement-based data of sulfur, chlorine and bromine releases from tropical volcanic eruptions with complex coupled chemistry climate model simulations taking radiative-dynamical-chemical feedbacks into account. Halogen model input parameters represent a size-time-region-wide average for the Central American eruptions over the last 200 ka ensuring a comprehensive perspective. The simulations reveal global, long-lasting impact on the ozone layer affecting atmospheric composition and circulation for a decade. Column ozone drops below 220 DU (ozone hole conditions) in the tropics, Arctic and Antarctica, increasing biologically active UV by 80 to 400%. Our model results could potentially be validated using high-resolution proxies from ice cores and pollen records.