“We have the tools and the know-how to limit global warming”, indicates Hoesung Lee, the president of the Intergovernmental Panel on Climate Change (IPCC), at the conclusion of the publication of the third chapter of their sixth report, this Monday, April 4.
→ ANALYSIS. The IPCC is alarmed by the already “irreversible” impacts of climate change
After a first part devoted to the physical bases of climate change published in August 2021, a second focused on our vulnerability and our possibilities of adaptation in February, the latter was the most anticipated. It assesses, for the first time since a previous report in 2014, the range of solutions available to us to reduce our greenhouse gas emissions, based on existing scientific literature.
Peak emissions before 2025
Despite the climate policies implemented in recent years, greenhouse gas emissions continue to rise globally. To stay below the 2°C warming mark at the end of the century, CO2 emissions would have to peak before 2025 and then decrease by 27% by 2030 (and even by 43% to hope to limit global temperature rise to 1.5°C).
→ EXPLANATION. How are IPCC reports produced?
These scenarios imply also drastically reducing emissions of methane, another powerful greenhouse gas resulting in particular from fossil fuels, the waste sector and agriculture.
“The central message of the report is that there are options to reduce emissions in all sectors,” emphasizes Franck Lecocq, senior researcher at AgroParisTech and co-author. If we take greenhouse gas emissions for the year 2019 as a benchmark, half could be avoided at a cost of less than 100 dollars (91 €) per tonne and a quarter at less than 20 dollars (18. €20), according to estimates made sector by sector (deployment of solar and wind power; reduction of deforestation and restoration of ecosystems; energy efficiency; change of fuel mode in the industry sector, etc.).
Lower cost of technologies
The report highlights the new options offered by the fall in the cost of certain technologies between 2010 and 2019: – 85% for solar energy and lithium batteries used for electric cars, – 55% for wind power. To the extent that “maintaining emissions-intensive systems may, in some regions and sectors, be more costly than transitioning to low-emissions systems,” points out the report, even if the figures vary greatly depending on the geographical areas. In addition, when it comes to the deployment of renewable energies on a large scale, technical challenges remain.
Act on demand
Another way of looking at things is that the IPCC was interested for the first time in demand-related emissions. Measures focused on our final consumption – telecommuting, use of carpooling, change of diet, etc. – could reduce global emissions by 40 to 70% by 2050. “This aspect is often referred to individual choices, explains Franck Lecocq. However, it involves changes in lifestyles, which greatly depend on existing infrastructure. » Unsurprisingly, the greatest source of emission savings to be made is in developed countries.