Volcanic and Solar Forcing

Volcanic eruptions and changes in the output of the Sun have been the dominant external drivers, or 'forcings,' of climate change during the Quaternary prior to the industrial revolution. A combination of proxy indicators have been used to study the magnitude and timing of changes in these forcings and the climate response. These include ice core records of volcanic particulate (aerosol) amounts and of cosmogenic isotopes that are correlated with solar output, and multiple indicators of surface temperature and precipitation. Comparison between the forcings and climate variability, and comparisons with results from climate model simulations, have shown that volcanic forcing typically played a major role in short-term (annual to decadal) climate variations, whereas solar forcing appears to have usually dominated on longer timescales at both the global and the regional scales.

Duke Scholars

Author Drew Todd Shindell Earth and Climate Sciences