The Paris Agreement adopted a target for global warming not to exceed 1.5°C. This sets a limit on the additional carbon we can add to the atmosphere – the carbon budget. Only around 17% of the carbon budget is now left. That is about 10 years at current emission rates.
Each country reports its annual greenhouse gas emissions to the United Nations. Scientists then set these emissions against estimates of the carbon absorbed by Earth’s natural carbon sinks. This is known as the bottom-up approach to calculating the carbon budget. Another way to track carbon sources and sinks is to measure the amounts of greenhouse gases in the atmosphere from space – the top-down approach.
As well as tracking atmospheric carbon, ESA’s Climate Change Initiative is using satellite observations to track other carbon stocks on land and sea.
(c) Planetary Visions (credit: ESA/Planetary Visions)esa.int