In December 2015, at the United Nations Conference on Climate Change (COP21), 196 countries adopted the Paris Agreement with the objective of keeping the increase in the global average temperature below 2°C, in relation to pre-industrial levels, and continue efforts to limit it to 1.5 °C.
Although this was perceived as a milestone in uniting all nations against climate change, actual promises to reduce greenhouse gases were far from being compatible with these goals for the coming decades.
But by COP26 in Glasgow, UK, in 2021, 120 countries had already updated their short-term targets and most of the major polluting economies (responsible for 70% of global carbon dioxide emissions) as well. emissions over the next 30 to 50 years.
Now, a new study by a global team led by the Basque Center for Climate Change (BC3), which includes Imperial College London and the National Technical University of Athens, shows that adding up all climate commitments, updated in the short and long term , is consistent with the Paris objective of limiting global temperature rise to well below 2°C.
Limiting global temperature rise is unlikely without meeting all climate commitments
However, the same work, published in Nature Climate Changewarns that achieving long-term net-zero emissions, after meeting current national targets for 2030, will provide a significant boost to mitigation efforts beyond that year in most countries.
It is unlikely, as stated in the note with which they release their analysis, that the increase in global temperature will be limited to 2°C, unless short- and long-term agreements are fulfilled. Furthermore, research indicates that even with current zero emissions scenarios, it is highly possible that the 1.5°C temperature threshold will be exceeded.
The results of this work indicate that we are moving to new ground in the public debate on mitigating climate change. “While until recently the focus has often been on making countries’ commitments more ambitious, our study shows that since COP26 in Glasgow, the most relevant factor in avoiding a climate disaster is ensuring the implementation of countries’ short-term and long-term commitments” , explains Dirk-Jan van de Ven, BC3 scientist leading the research.
By analyzing the impact of climate policies and what has been agreed by the main CO2 emitting countries, the article also assesses the extent to which energy and climate policies currently implemented are aligned with national objectives and the feasibility of each necessary decarbonization path, in socioeconomic terms, technological and physical terms.
“This analysis clearly establishes that making promises alone does not get us to deliver on the Paris Agreement: delivering what is promised means mitigation at an unprecedented speed and scale,” said Ajay Gambhir, researcher at Imperial College London.
Promises alone do not get us to the goal of the Paris Agreement
Ajay Gambhir, researcher at Imperial College London
As there are several tools with different strengths and weaknesses, the authors used four quantitative models to simulate the effects of current climate policies and commitments.
The models are broadly consistent with global emissions impacts, but the pathways from decarbonization to net zero futures differ considerably. Depending on the ways in which the models represent social, economic and technical systems, there are different “best” paths to zero emissions.
Each of these decarbonization paths has its own particularities and creates different challenges for each region when it comes to achieving its climate goals. For example, some of these pathways affect the socioeconomic context, for what they can mean in terms of reduced consumption.
On the other hand, two other of these paths are marked by challenges to increase the deployment of renewable energies, such as wind energy, photovoltaics, sustainable bioenergy or carbon capture technologies.
“However, what is most interesting is that different major economies face very different dilemmas in achieving their common goal of keeping the average global temperature rise below 2°C, showing that there really is no one-size-fits-all policy or technology approach. to ensure that the objective of the Paris Agreement is kept alive across the world,” concludes Alexandros Nikas, researcher at the National Technical University of Athens.
Reference:
Van den Ven, Dirk-Jan et al. “A multi-model analysis of post-Glasgow climate targets and feasibility challenges”. Nature Climate Change (2023)