Global Warming Potential Calculator Formula
Understand the math behind the global warming potential calculator. Each variable explained with a worked example.
Formulas Used
CO2-Equivalent
co2_equivalent = gas_mass_kg * gwp_factorCO2-Equivalent (tonnes)
co2_equiv_tonnes = gas_mass_kg * gwp_factor / 1000Variables
| Variable | Description | Default |
|---|---|---|
gas_mass_kg | Mass of Gas Emitted(kg) | 100 |
gwp_factor | GWP Factor (relative to CO2) | 28 |
How It Works
Understanding Global Warming Potential
Global Warming Potential (GWP) compares the heat-trapping ability of a greenhouse gas to CO2 over a specified period, typically 100 years.
Formula
CO2-Equivalent (kg) = Mass of Gas (kg) x GWP Factor
Common GWP-100 values: Methane (CH4) = 28, Nitrous Oxide (N2O) = 265, SF6 = 23,500. A higher GWP means the gas traps more heat per kilogram than CO2.
Worked Example
A farm releases 100 kg of methane (GWP = 28) over a year.
- 01CO2-equivalent = 100 kg x 28 = 2,800 kg CO2e
- 02In tonnes: 2,800 / 1,000 = 2.8 tonnes CO2e
Frequently Asked Questions
What does GWP-100 mean?
GWP-100 measures the total warming effect of a gas over 100 years relative to CO2. It is the most commonly used time horizon in climate policy.
Why is methane GWP so much higher than CO2?
Methane absorbs infrared radiation about 80 times more effectively than CO2 over 20 years, but it breaks down faster, so the 100-year GWP is 28.
Where do GWP values come from?
The Intergovernmental Panel on Climate Change (IPCC) publishes GWP values in its assessment reports. The latest values come from the AR6 report.
Ready to run the numbers?
Open Global Warming Potential Calculator