“Only immediate, ambitious and coordinated measures can allow us to avoid serious damage” of the climate crisis. the Intergovernmental Panel on Climate Change (IPCC) detailed, on Monday April 4 in the third part of its sixth report, the solutions to be implemented to reduce our greenhouse gas emissions, drivers of global warming. . Their cost is “less compared to the cost of inaction”insists to franceinfo Céline Guivarch, director of research at the International Center for Research on the Environment and Development (Cired) and co-author of this new IPCC report.
Franceinfo: What are the main messages of this report?
This third component focuses on the mitigation of greenhouse gas emissions. It scans all major sectors: cities, energy, agriculture… What it shows is that there are mitigation options available today in all sectors, capable of reducing our gas emissions. greenhouse effect significantly and at a reasonable cost. These options are multiple: some are based on available technologies, others on transformations of our production methods, our infrastructures or our social organizations. The report is extremely clear: it is a panel of levers which, mobilized together, are able to significantly reduce emissions. The exact composition is up to politicians, public debate and territories to adopt.
“One of the robust findings of this report is that the cost of action is less important than the cost of inaction. Reducing our emissions is a worthwhile long-term investment.”
Céline Guivarch, co-author of group 3 of the IPCCat franceinfo
What does it add compared to the last publication, which dates from 2014?
The global context has changed. Since the last report, research has been able to focus on measures already implemented. But unfortunately, emissions continued to rise. So, as with climate change, what counts is the accumulation of emissions, we are more in a hurry. We find ourselves saying today that only immediate, ambitious and globally coordinated measures can enable us to avoid serious damage.
This report presents a range of solutions, but is not a list of recommendations. Can you explain the IPCC approach?
We do an assessment of the state of knowledge. For this report, we evaluated more than 18,000 articles to look, very collectively, at each mitigation option, their potential, their cost, their implication on inequalities, development or biodiversity. We also assess the literature on the trajectories that put all these options together, the public policy instruments, put in place or which could be put in place, what has worked or not…
The 6th report process started in 2017 with the adoption of the table of contents. Based on these chapters, there is a call for authors. It is then the team of authors who takes the mandate of what is treated in the report and evaluates the literature of these elements.
At the end of the process, there is an exchange between the authors, scientists, and representatives of each member state of the IPCC. And sometimes they try to tone down the language used. How did it go this time?
It is an intense process to discuss with more than 100 delegations, remotely. What is important is that it is the authors who hold the pen. They guarantee that the summary reflects the underlying report in a balanced way, that everything in the summary corresponds to the state of knowledge. NOTWe always have the last word. The role of the State delegations is that this summary be as clear as possible, as audible as possible. Some delegations come, with their strong economic and geopolitical stakes. It is always on part 3, because we are talking about solutions, that the discussions are the longest.
Can you give some examples of solutions assessed in this report?
Take transport. There are options that will seek to play on the demand for transport services, to avoid certain movements of goods or people: optimizing the production chain, rethinking urban planning to have shorter distances, teleworking or telemeeting.. Other options aim to promote modal shift towards less emitting modes of transport: public transport, cycling, walking. Behind this, there are transformations of our infrastructures, our organizations and our social norms. Finally, you have more directly technological options: more energy-efficient, lighter and electrified vehicles, provided that the electricity is produced in a clean manner.
For buildings, there is the transformation of existing constructions, to insulate them, the materials used for new construction or heating. When it comes to agriculture, opting for less meat-based diets is part of the range of options. This of course depends on the country, it is sometimes a question of food security, but there are regions of the world where there is a potential for reduction.
This report also addresses the thorny issue of capturing the carbon already emitted. What does he say?
The report shows very clearly that if we want to stabilize the increase in global temperature, we must achieve net zero emissions on a global scale. This means a reduction of positive emissions, immediate and rapid, to have the lowest possible residual emissions. But it also means that we need negative emissions to compensate for these residual emissions, in agriculture and aviation for example.
However, this is not to say that we can continue to emit greenhouse gases. The lower the residual emissions, the less negative emissions are needed to offset them.
“We can’t say to ourselves: ‘No matter what we emit today, in 30 years, we will have magic solutions.'”
Céline Guivarch, co-author of the reportat franceinfo
There are already options used today: reforestation, changes in land use practices, agroforestry… There are other types of solutions, which are at the research and prototype stages today. today, of geological capture and storage. They do not have zero potential, but they also have, if they are deployed on a large scale, negative effects: competition with the use of land and water, food security, threat to biodiversity or the rights of populations. native. Direct capture is also an expensive solution, which requires a lot of energy.
This report, which includes a “summary for decision-makers”, is published a few days before the first round of the presidential election in France. Do you have something to say to the candidates?
Read this report and heed the extremely clear call for immediate and ambitious action across all sectors.