Volcanic eruptions over the past decade or so have cooled global lower-atmosphere temperatures to a statistically significant degree, concludes an article published online in Nature Geoscience. Incorporating these volcanic influences into climate models reduces the difference between observed and computer-simulated surface temperature trends between 1998 and 2012 by up to 15%.

Benjamin Santer and colleagues analysed satellite data to show that volcanic aerosols released from several eruptions since 2000 had a discernable cooling effect on the lower layers of the atmosphere. The authors go on to estimate the magnitude of the effect in climate model simulations, and conclude that the lack of volcanic influences in model simulations of twenty-first-century climate can explain some of the overestimation of warming in these simulations of global mean surface temperatures, compared with observations.