Speaker
Dr Ewa Bednarz
Chemical Sciences Laboratory – National Oceanic and Atmospheric Administration – NOAA
Understanding and narrowing the uncertainties in atmospheric circulation, ozone and climate response to Stratospheric Aerosol Injection
The injection of stratospheric aerosol precursor into the lower stratosphere (SAI) has been proposed to mitigate some of the negative impacts of rising greenhouse gas levels. Despite offsetting global mean surface temperature, various studies demonstrated that SAI could also have important impacts on stratospheric and tropospheric circulation – thereby potentially playing an important role in modulating regional climate variability – as well as influence the recovery of stratospheric ozone. In this talk I will give an overview of some of such SAI impacts, demonstrate the dependence of the model stratospheric and tropospheric responses on the specifics of SAI realization (i.e. strategy and scenario), as well as discuss the role of inter-model uncertainties. Overall, I will show examples of recent work in this area that contribute to an increased understanding of the underlying radiative, chemical and dynamical processes – including their coupling – that drive the atmospheric and climate response to SAI, and help to isolate and narrow the associated uncertainties.