Radiative Forcing Calculator
Estimate the radiative forcing from a change in atmospheric CO2 concentration using the simplified logarithmic relationship.
ppm
ppm
Radiative Forcing
2.169 W/m²
Radiative Forcing vs Initial CO2 Concentration
Radiative Forcing from CO2
Radiative forcing measures the change in energy balance at the top of the atmosphere caused by a change in CO2 concentration.
Formula
Delta F = 5.35 x ln(C / C0) W/m²
Where C is the new concentration and C0 is the reference (pre-industrial) concentration. The natural logarithm reflects the diminishing absorption effect as CO2 levels rise.
Example Calculation
CO2 has risen from 280 ppm (pre-industrial) to 420 ppm (current).
- 01Ratio = 420 / 280 = 1.5
- 02ln(1.5) = 0.4055
- 03Delta F = 5.35 x 0.4055 = 2.169 W/m²