Effect of volcanic eruptions significantly underestimated in climate projections

Science Daily  June 23, 2023
Standard climate projections, as in Intergovernmental Panel on Climate Change Sixth Assessment Report, assume that explosive volcanic activity over 2015–2100 are of the same level as the 1850–2014 period. Researchers in the UK used the latest ice-core and satellite records to design stochastic eruption scenarios, to show that there is a 95% probability that explosive eruptions could emit more sulfur dioxide (SO2) into the stratosphere over 2015–2100 than current standard climate projections (i.e., ScenarioMIP). Their simulations using the UK Earth System Model with interactive stratospheric aerosols showed that for a median future eruption scenario, the 2015–2100 average global-mean stratospheric aerosol optical depth (SAOD) was double that used in ScenarioMIP, with small-magnitude eruptions (<3 Tg of SO2) contributing 50% to SAOD perturbations. They showed that volcanic effects on large-scale climate indicators, including global surface temperature, sea level and sea ice extent, are underestimated in ScenarioMIP because current climate projections do not fully account for the recurrent frequency of volcanic eruptions of different magnitudes… read more. Open Access TECHNICAL ARTICLE 

a) Annual eruption probability based on ice-core… Credit:  Geophysical Research LettersVolume 50, Issue 12 e2023GL103743, 13 June 2023