Limited climate response of very large volcanic eruptions

Extremely large volcanic eruptions have been linked to global climate change, biotic turnover, and, for the Younger Toba Tuff eruption 74,000 years ago, near‐extinction of modern humans. One of the largest uncertainties of the estimated climate effects in previous model studies involves the aerosol size distribution. A huge sulfate load causes higher collision rates, larger particle sizes, and rapid fall out, which in turn greatly affects radiative feedbacks. Incorporating aerosol microphysical processes into global model simulations results in a smaller climate effect than estimated before.