Sensitivity of total column ozone to stratospheric sulfur injection strategies

We explore the impact of different stratospheric sulfur injection strategies to counter greenhouse gas induced warming on total column ozone (TCO), including high and low altitude injections at four latitudes, equatorial injections, and using a configuration with higher vertical resolution, based on a state-of-the-art Earth system model. The experiments maintain global surface temperatures at 2020 conditions, while following the unmitigated future scenario.

Within the first 10 years of the injection, we find an abrupt deepening of the Antarctic ozone hole by 8%-20% and changes up to +/- 5% for other regions and seasons. The ozone hole recovery is delayed by similar to 25 to over 55 years, with the fastest recovery for low-altitude injections and slowest for equatorial injections. Mid to high-latitude TCO increases by similar to 15% in Northern Hemisphere winter and spring between 2010-2019 and 2080-2089 due to both increasing greenhouse gases and increasing sulfur injections.