Abstract:
Volcanism is a major driver of climate variability and has played a critical role in the long-term evolution of Earth’s atmosphere and habitability through the release of gases including sulfur species, water vapour, carbon dioxide, and halogens. In this talk, I will summarize my work on volcanic radiative forcing exerted by volcanic eruptions of different magnitudes in the past and in the future. The general mechanisms by which volcanic eruptions affect climate are well understood today. Until recently, research efforts have mainly focused on the direct radiative, dynamical and chemical effects of sulfate aerosol particles formed by large-magnitude explosive eruptions such as Mt. Pinatubo in 1991. However, eruptions considerably smaller in magnitude than 1991 Mt. Pinatubo routinely decrease the transparency of the stratosphere to a degree that a cooling effect is discernible in upper tropospheric temperature measurements. I will make a case for the need to include these small-magnitude eruptions in climate model simulations. I will also show that global warming can affect both eruptive column dynamics and the volcanic sulfate aerosol lifecycle, thereby influencing the radiative forcing and climate effects of future volcanic eruptions. In addition, I advocate for a new, consistent metric – the Volcano-Climate Index (VCI) – to categorize the climate response to eruptions that differ in size, style, and duration to facilitate socio-economic risk assessments.
What is the Joint Oslo Seminar (JOS):
- Atmospheric and climate sciences have a stronghold in Oslo among the four institutions University of Oslo, the Meteorological Institute, CICERO and NILU.
- This joint seminar invites renowned international experts to contribute to an informal series of lectures, meant to create interaction with the Oslo atmospheric and climate science community on recent highlights and analysis in the field.
- Normally seminars will be held on Thursdays (12:15 pm -1pm).