Speaker
Description
Despite solar radiation being the primary external energy source driving the Earth’s climate system, the climatic impact of its long- term variations – such as prolonged periods of low solar activity called Grand Minima – still remains debatable due to the wide spread in solar irradiance reconstructions. Given the large implica- tions for detection and attribution studies, particularly to interprete past climate changes or to reduce the uncertainty in future climate projections, it is of great importance to disentangle the “direct” response to the solar signal from both natural and anthropogenic drivers and from the background “noise” represented by internal variability.
In this work we assess the response of the climate system to a solar grand minimum like the Maunder Minimum using the Isca intermediate-complexity General Circulation Model (GCM) from the University of Exeter, and possibly higher-complexity GCMs in the near future. We perform simulations with and without consis- tent ozone variations, thus isolating the contribution of the “top- down” stratospheric ozone-dynamic coupling from effects primarily driven by tropospheric dynamics. In this context, polar regions seem to play a key role as early or amplified indicators of solar-induced climatic changes.