Dear Colleagues,
COMET (The Centre for Observation and Modelling of Earthquakes, Volcanoes, and Tectonics) invites you to the next installment of our COMET+ webinar series, viewable from the home office.
Impacts of climate change on the stratospheric volcanic sulfate aerosol lifecycle and radiative forcing from tropical eruptions
Friday 29th September 2021 at 2pm UK time (1pm UTC / 3pm CEST / 6am PDT)
Dr Thomas J. Aubry
University of Cambridge, UK
Please register at: Webinar Registration - Zoom
(After registering, you will receive a confirmation email containing information on how to join the webinar)
Abstract:
Whereas the impact of volcanic eruption on climate is a mainstream research topic, how climate change will alter volcanic processes remains largely understudied despite rapid changes in the Earth System driven by anthropogenic activities. In particular, the impacts of climate change on the stratospheric volcanic sulfate aerosol lifecycle and radiative forcing remains unexplored. Combining an eruptive column model with an aerosol-climate model, I will show that the stratospheric aerosol optical depth perturbation from frequent moderate-magnitude tropical eruptions (e.g. Nabro 2011) could be reduced by 75% in a high-end warming scenario compared to today, a consequence of future tropopause height rise and unchanged eruptive column height. In contrast, global-mean radiative forcing, stratospheric warming and surface cooling from infrequent large-magnitude tropical eruptions (e.g. Mt. Pinatubo 1991) is projected to increase by 30%, 52 and 15% in the future, respectively. These changes are driven by an aerosol size decrease, mainly caused by the acceleration of the Brewer-Dobson circulation, and an increase in eruptive column height. Quantifying changes in both eruptive column dynamics and aerosol lifecycle is therefore key to assessing the climate response to future eruptions. I will discuss the limitations of models used to investigate climate-volcano feedbacks and ongoing validation efforts. Last, I will discuss how climate-volcano feedbacks affecting different volcanic processes, such as those related to deglaciation and eruption frequency, could combine with feedbacks related to the sulfate aerosol lifecycle to shape future volcanic influences on climate.
The COMET+ webinar series promotes research by collaborators of COMET scientists. We aim to provide a platform for these researchers to showcase their work to large and international audiences, opening doors to broader collaborative networks and enhancing the community’s diversity of backgrounds and ideas.
Catch up on past COMET and COMET+ webinars on our YouTube page: https://www.youtube.com/channel/UCtFDytX1hgjvlS4NH48M2oQ/videos
Best wishes,
Tamarah King & Chris Rollins
COMET - Centre for the Observation and Modelling of Earthquakes, Volcanoes and Tectonics
@NERC_COMET