Might dimming the sun change atmospheric ENSO teleconnections as we know them

We use a troposphere–stratosphere chemistry-climate model to investigate the impact of a 10% reduction in solar irradiance. Starting from the changes in global mean surface temperature modelled, we study changes of forced atmospheric variability. Large increases in ozone interacting with the meteorology are modelled, exemplified by changes in El Nino/Southern Oscillation (ENSO)-related teleconnection patterns. The observed Northern Hemisphere centre of action at 50 hPa, modelled in our base integration, disappears in the run with reduced solar irradiance. This change in forced stratospheric variability highlights the point that the assessment of geoengineering schemes need to consider many possible feedbacks. Copyright © 2010 Royal Meteorological Society

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