In December 2015, at the United Nations Conference on Climate Change (COP21), 196 countries adopted the Paris Agreement and continued efforts to limit the increase in global average temperature to well below 2 °C compared to pre-industrial levels. Limit it to 1.5°C.
Although this was considered a milestone in the League of Nations Against Climate Change, the actual promises of greenhouse gas reductions were far from compatible with these objectives for the next decades.
But by COP26 in Glasgow, UK in 2021, 120 countries had already updated their short-term targets and most major polluting economies (accounting for 70% of global carbon dioxide emissions) had also. He expressed his commitment to move towards net zero 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, in the short and long term The updated term, it is well suited to the Paris objective of limiting the increase in global temperature to well below 2°C.
Limiting global temperature rise is not possible without meeting all climate commitments
However, the same work, published in Nature Climate Change, warns that achieving net zero emissions in the long term after reaching the current national targets for 2030 will mean that most countries will need to significantly increase mitigation efforts after that year. .
It is unlikely, as reported in the note with which they disclose their analysis, that the rise in global temperatures will be limited to 2 °C unless short- and long-term agreements are met. Furthermore, research indicates that even with current zero emissions scenarios, it is highly likely that the 1.5 °C temperature threshold will be exceeded.
The results of this work indicate that we are moving into new areas in the public debate on climate change mitigation. “While until recently the focus was often on making country commitments more ambitious, our study shows that, since COP26 in Glasgow, the most relevant factor in avoiding a climate disaster is ensuring implementation in the short and long term.” Long-term commitments from countries”, explains Dirk-Jan van de Ven, the BC3 scientist who led the research.
By analyzing the impact of climate policies and what has been agreed upon by the main CO2 emitting countries, the article also assesses the extent to which currently implemented energy and climate policies are aligned with national objectives, and each decarbonisation in socioeconomic How much is needed to achieve the trajectory. , technical and physical conditions.
Ajay Gambhir, a research fellow at Imperial College London, said: “This analysis makes clear that simply making promises does not help us deliver on the Paris Agreement: delivering on what has been promised means delivering on unprecedented speed and scale.” Shaman is.”
Resolutions themselves don’t get us to the Paris Agreement goals
Ajay Gambhir, Research Fellow at Imperial College London
As there are many instruments with different strengths and weaknesses, the authors used four quantitative models to simulate the effects of current climate policies and commitments.
The models are largely consistent with global emissions impacts, but the decarbonization pathways for net-zero futures differ significantly. There are different “best” paths to zero emissions depending on the way the models represent social, economic and technological systems.
Each of these decarbonization pathways has its own characteristics and poses different challenges for each region when it comes to achieving its climate goals. For example, some of these pathways affect the socioeconomic context, what they might mean in terms of reduced consumption.
On the other hand, two of these other paths are marked by challenges in increasing the deployment of renewable energy, such as wind power, photovoltaics, sustainable bioenergy or carbon capture technologies.
“However, what is most interesting is that different major economies face very different dilemmas in meeting their shared goal of keeping the average global temperature increase below 2°C, indicating that policy or unique technical approach to ensure that the goals of the Paris Agreement are kept alive worldwide”, concluded Alexandros Nikas, a researcher at the National Technical University of Athens.
Reference:
Van Den Ven, Dirk-Jan et al. “A multi-model analysis of Glasgow’s post-climate targets and viability challenges”. Nature Climate Change (2023)
