“We discovered that 30 per cent of the regions for which data is available have completely separated carbon emissions from economic growth. This successful decoupling is mainly seen in regions with high incomes and historically carbon-intensive industries, as well as those with substantial portions of their economies dedicated to services and manufacturing. These areas are notably effective at reducing carbon emissions while still fostering economic expansion,” remarks Anders Levermann, co-author and leader of the research department ‘Complexity Science’ at the Potsdam Institute for Climate Impact Research (PIK). “To stabilise the global mean temperature, achieving net-zero carbon emissions is imperative. If economies are to expand, their growth must not be linked to CO2 emissions.”

Localised climate initiatives further bolster the momentum behind successful decoupling. “Particularly in the EU, cities that have enacted climate mitigation strategies and regions that have benefitted from increased financial support for climate-related actions show higher rates of successful decoupling,” explains Maria Zioga, a PIK scientist and the study’s lead author. “Europe consistently surpasses other regions, with many of its areas showing a steady trend of decoupling over the last two decades. In comparison, North America and Asia have experienced more variable patterns of decoupling throughout the years, although there have been signs of improvement in the last decade,” she adds.

However, fewer than half of the regions are on track to achieve net-zero carbon emissions by 2050.

Unlike previous studies focusing on national or city-specific carbon decoupling, the PIK team adopted a more detailed, globally encompassing approach by analysing the economic outputs of 1,500 subnational regions. These regions, responsible for 85% of global emissions, showed an increase in per capita gross regional product (GRP). The team integrated this economic data with grid-based records of production-based carbon emission intensities over the last 30 years, revealing significant decoupling patterns worldwide. Although the study does not account for consumption-based emissions at a subnational level, which could show the impact of international trade, it still offers crucial insights into global decoupling trends.

The researchers also projected the years in which net-zero emissions might be reached for each region by examining historical decoupling trends and their effects on emissions reductions. “Developed regions are more likely to meet these targets ahead of others; however, the recent trends suggest that achieving net-zero by the middle of this century will be challenging for most regions,” concludes Max Kotz, a PIK guest researcher and a scientist at the institute when the study was conducted. “Given the current rates of decoupling, less than half of the subnational regions will manage to reach net-zero carbon emissions by 2050. Thus, it is crucial for all levels of government, especially those in developed nations, to intensify their efforts and increase investment in the energy transition, particularly in the Global South, to meet global net-zero targets,” he emphasises.

More information: Maria Zioga et al, Observed carbon decoupling of subnational production insufficient for net-zero goal by 2050, Proceedings of the National Academy of Sciences. DOI: 10.1073/pnas.2411419121

Journal information: Proceedings of the National Academy of Sciences Provided by Potsdam Institute for Climate Impact Research (PIK)