UK researchers have developed an accurate new method for measuring global carbon emissions.
A recent study conducted by a collaboration of scientists from the University of Exeter, Met Office, and Imperial College has unveiled a novel approach to gauge the total global carbon emissions aligned with the Paris Agreement goals of limiting global warming to 1.5°C and 2°C.
The research is critical as concerns mount over the Earth’s warming trend. Despite 2023 experiencing temperatures perilously close to breaching the 1.5°C threshold, the Paris targets are concerned with the average temperature rise over a decade or more.
Lead author Peter Cox, Director of the Global Systems Institute at the University of Exeter, said: “Our study clarifies the climate problem that needs to be solved, and we hope that it will stimulate greater efforts to reduce our emissions to net zero.”
Understanding global carbon emissions
Approximately 15 years ago, climate scientists stumbled upon a pivotal revelation about climate change dynamics.
They discerned that cumulative carbon dioxide emissions predominantly dictate the trajectory of global warming since the onset of industrialisation.
This breakthrough paved the way for delineating total carbon budgets consistent with the Paris objectives, defining ‘net zero’ as the tipping point where global warming halts.
Inaccuracies in climate models
One major hurdle has been the disparities among Earth System Models in predicting the relationship between global carbon emissions and global warming.
However, the new study circumvents this obstacle through what the authors term an ’emergent constraint’.
Essentially, this approach entails synthesising data from diverse models to establish a linear correlation between historical global carbon emissions and observed warming, enabling projections of future emissions compatible with Paris targets.
Encouragingly, the findings suggest emissions budgets that exceed the average values projected by existing models by at least 10%.
However, the reality remains that if current emission rates persist, humanity has just over a decade before breaching the 1.5°C threshold delineated by the Paris Agreement, even when considering decade-long averages of warming.
Co-author Chris Jones, from the Met Office, added: “This emergent constraint is elegant and powerful. It uses observations to narrow the possible range of future emissions, but it also lets us consider other greenhouse gases other than just CO2. In this way, the remaining carbon budget is made much more policy relevant.”
As the world grapples with the imperative to curb global carbon emissions and mitigate climate change, the insights from this study offer a roadmap for policymakers and stakeholders.
Urgent action is warranted to align our carbon trajectory with the Paris goals and avert the most catastrophic consequences of climate change.
