Carbon Budget Remaining Calculator

Estimate the remaining global carbon budget for a target temperature limit based on current emission rates.

Gt CO2
Gt CO2/yr
years

Budget Remaining

260 Gt CO2

Years Until Exhausted6.5 years
Budget Already Used48.0 %

Budget Remaining vs Years Elapsed Since 2020

The Global Carbon Budget

The carbon budget is the total amount of CO2 that can still be emitted while keeping global warming below a specific temperature target.

Formula

Remaining Budget = Total Budget - (Annual Emissions x Years Elapsed)

Years Left = Remaining Budget / Annual Emissions

The IPCC estimates that for a 50% chance of staying below 1.5°C, the remaining budget from 2020 was about 500 Gt CO2. At current rates of ~40 Gt/year, this budget is rapidly shrinking.

Example Calculation

Starting budget of 500 Gt CO2 from 2020 with 40 Gt/year emissions, 6 years later.

  1. 01CO2 used = 40 x 6 = 240 Gt CO2
  2. 02Remaining = 500 - 240 = 260 Gt CO2
  3. 03Years left = 260 / 40 = 6.5 years
  4. 04Budget used = 240 / 500 x 100 = 48.0%

Frequently Asked Questions

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