Carbon budget
Topic: Environment and Sustainable Development · NCERT: Beyond NCERT
Meaning
A carbon budget is the total amount of carbon dioxide the world can still emit while keeping warming below a set limit, such as 1.5°C. It works like a bank balance. Every tonne emitted is withdrawn for good, so the faster we emit, the sooner the budget runs out. It also raises a fairness question. Developed countries used up most of the historical budget. That is the basis of CBDR (common but differentiated responsibilities), the principle that all countries share the duty to act but rich countries should do more.
Example
The IPCC's Sixth Assessment Report (AR6) put the budget at about 500 GtCO2 from 2020 for a 50% chance of staying at 1.5°C. The world emits about 40 GtCO2 a year. So only a little over a decade of emissions at that rate was left, and the budget is now much smaller.
Don't confuse with
- Carbon footprint: this is the emissions of one person, firm, product or country, in CO2-equivalent. It measures what one emitter releases. The carbon budget is the limit on total future emissions for the whole world.