Radiative Forcing Calculator Formula

Understand the math behind the radiative forcing calculator. Each variable explained with a worked example.

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Formulas Used

Radiative Forcing

delta_f = 5.35 * log(co2_final / co2_initial)

Variables

VariableDescriptionDefault
co2_initialInitial CO2 Concentration(ppm)280
co2_finalFinal CO2 Concentration(ppm)420

How It Works

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.

Worked Example

CO2 has risen from 280 ppm (pre-industrial) to 420 ppm (current).

co2_initial = 280co2_final = 420
  1. 01Ratio = 420 / 280 = 1.5
  2. 02ln(1.5) = 0.4055
  3. 03Delta F = 5.35 x 0.4055 = 2.169 W/m²

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