A new explainer from the RSS Climate Change Task Force examines one of the most important questions in climate policy: has the 2015 Paris Climate Agreement actually worked?
The landmark agreement, signed by 195 countries in December 2015, sought to limit the rise in global average temperature to well below 2°C above pre-industrial levels, with a target of 1.5°C. Our explainer uses emissions data from 2015-2024 and statistical modelling to assess how global climate prospects have changed since the agreement was signed.
Overall, the analysis finds a mixed picture. While carbon intensity - the amount of carbon emitted per unit of GDP - has fallen substantially since 2015, overall global emissions have continued to rise as economic growth has outweighed these gains. The median projected temperature rise by 2100 has fallen slightly from 2.6°C (based on analysis before the Paris Agreement) to 2.4°C. The probability of the most severe outcome has also declined, with the chance of warming exceeding 3°C falling from 26% to 9%.
Despite small improvements, it is clear that progress is not on track to meet the objectives of the Paris Agreement, with only a 17% chance of keeping warming below 2°C. There is – however – still cause for hope. Projections suggest that if countries fulfil their existing commitments under the agreement to 2030, and then continue efforts at the same level, warming could be limited to 2.1°C.
The explainer illustrates the crucial role of statistics in climate science. From projecting future emissions to estimating the likelihood of different warming scenarios, statistical models help turn vast quantities of data into evidence that can inform policy and public understanding. As countries prepare for the next phase of climate action, robust statistical analysis will remain vital for tracking progress, evaluating what works and identifying where further action is needed.
This explainer is part of the RSS Climate Change Task Force’s series of accessible guides, designed to help people understand the statistics and evidence underpinning climate change.
Read the explainer in full.