By adopting the Paris Agreement governments have promised to “pursue efforts” to keep global temperature increase to 1.5°C above pre industrial levels. But how much realistic is this promise? A new study published on Nature Climate Change tried to answer the question, with the contribution of CMCC researchers Johannes Emmerling, Laurent Drouet, and Massimo Tavoni. The modelling effort included for the first time not only technological development and financial needs, but also socioeconomic conditions such as inequalities, political will in pursuing sustainability, and international cooperation.

The researchers used six integrated assessment models to model different scenarios in line with the 1.5°C limit under five so-called Shared Socioeconomic Pathways (SSPs).
The results of the study, titled “Scenarios towards limiting global mean temperature increase below 1.5 °C”, showed that the 1.5°C target is feasible but not in all cases: strong social and economic inequalities, continued use of fossil-fuels, poor international cooperation and fragmented climate policies are key barriers to reaching the 1.5°C goal.

Which conditions allow to limit the increase in temperature within the established threshold? In order to achieve the 1.5°C goal, greenhouse gas emissions should peak by 2030 and decline rapidly over the following decades, attaining carbon neutrality around the middle of this century. The successful scenarios include a shift away from unabated fossil fuel use (without carbon capture and storage), a rapid scale up of renewable energy sources, a reduction in energy use through efficiency improvements, and the deployment of Negative Emissions Technologies, such as bioenergy with carbon capture and storage (BECCS), afforestation and reforestation, to remove the buildup of CO2 in the atmosphere.

Developed under the European project CD-LINKS, the 1.5°C socioeconomic pathways will serve as a starting point for further research, which can help policy-makers to understand the real-world implications of these scenarios, the authors said.
Financed by the European Commission’s Horizon 2020 programme, the research project CD-LINKS brings together a consortium of 19 leading international research organizations, including the CMCC, to improve understanding of the linkages between climate change policies and the Sustainable Development Goals adopted in 2015.