New Study: Lower Bound Uncertainty In Aerosol Forcing 10 Times Larger Than 10 Years Of CO2 Forcing
By Kenneth Richard on 30. October 2023
“Despite two decades of advances in many aspects of aerosol-climate science, aerosol climate forcing uncertainty is virtually undiminished. Yet, reducing this uncertainty is critical for any effort to attribute, mitigate, or predict climate changes.” – Kahn et al., 2023
According to a new study, the lower-bound uncertainty in natural aerosol forcing from wildfire smoke, desert dust, volcanic and pollution particles – not including the aerosol-induced cloud formation effects modulating Earth’s radiation budget – is 2.2 W/m² (±1.1 W/m²).
“A lower bound on the uncertainty range of just the direct component of the total global-mean all-sky aerosol forcing (i.e., that due to scattering and absorption by airborne particles but not their indirect effects on clouds) is estimated as ±1.1 W/m²”
To put this uncertainty estimate into perspective, it takes 10 years of CO2 concentration increase (22 ppm) to produce a surface forcing of 0.2 W/m² – and this is only for clear-sky, or an imaginary world in which no clouds exist (Feldman et al., 2015). CO2 forcing over a span of a decade is thus 10 times smaller than the lower-bound uncertainty in natural aerosol forcing.
https://notrickszone.com/2023/10/30/new-study-lower-bound-uncertainty-in-aerosol-forcing-10-times-larger-than-10-years-of-co2-forcing/
