From the CO2Science Archive: Statistical properties of climatically significant volcanic eruptions over the last 600 years were analyzed in an effort to estimate the probability of future eruptions over the next decade.
Paper reviewed: Hyde, W.T. and Crowley, T.J. 2000. Probability of future climatically significant volcanic eruptions. Journal of Climate 13: 1445-1450.
What was learned
The authors determined that there is a 35% to 40% probability of a volcanic eruption with the capability of producing a radiative perturbation of -1 Wm-2 or larger in the next 10 years. Such an eruption is estimated to produce a 0.1C to 0.15C cooling over a 2-3 year period. The probability of a larger, Mt. Pinatubo-scale, eruption with a radiative perturbation of -3 Wm-2 is 15% to 25%.
What it means
The authors are concerned with the idea that were a major volcanic eruption to occur in the next decade – which seems a fairly good possibility – it could “mask the CO2 effect and complicate discussions on a greenhouse gas protocol.” They are correct; but that’s how the real world operates.
Hunga-Tonga’s minor effect (nothing for 14 months, then el Nino warming that had nothing to do with HT) seems to indicate that aerosol forcings, which were largely determined from what were assumed to be the effects of Pinatubo, might be suspect.
I am both History and Science student, my belief is that during this Interglacial temperatures have been rising steadily until they met an obstacle-2 in the last 1500 years- the event of 536,little publicised but dramatically destructive,and the Maunder Minimum ,Solar Radiation reducing. If it weren’t for these fences along the path we’d be much warmer but we know these events occur regularly because,unlike the Alarmists,we have evidence.