Surprising similarities in model and observational aerosol radiative forcing estimates

Observation-based studies have typically found a smaller aerosol effective radiative forcing than in model simulations and were given preferential weighting in the Intergovernmental Panel on Climate Change (IPCC) Fifth Assessment Report (AR5). With their own sources of uncertainty, it is not clear that observation-based estimates are more reliable.

Understanding the source of the model and observational differences is thus vital to reduce uncertainty in the impact of aerosols on the climate.