While COP29 started in Baku two days ago, the report Global Carbon Budget reveals that CO2 equivalent emissions increased by 2% worldwide between 2023 and 2024. They return to the average rate observed during the decade 2004-2013 and move away from the -3.9% annual reduction which would be necessary by 2050 to achieve carbon neutrality by this time. This is the main lesson of this report produced by an international team of more than 120 scientists, which has provided a peer-reviewed annual update of global emissions for almost 20 years.
Its conclusion for 2024: the concentration of CO2 in the atmosphere rises to 422.5 ppm (parts per million), or 52% more than in the pre-industrial era. If the 2024 trend continues, there are six years left before exceeding the global carbon budget to limit warming to +1.5°C, and 27 years for 2°C.
This increase can be explained by two essential factors: an increase in emissions linked to fossil fuels despite strong growth in clean energies, and natural carbon sinks (oceans and forests) themselves victims of climate change and affected by extraordinary fires, which are no longer able to play their role as effectively.
The probable Chinese peak of fossil fuels
Emissions from fossil fuels continue to increase, slightly for oil and coal (except in India), more strongly for natural gas, whose emissions are only decreasing within the European Union.
Those of cement, a material resulting from the combustion of a limestone compound itself transformed into clinker, which accounts for 4% of global emissions, are also taken into account. Their spectacular decline (-8%) in China, “ undoubtedly under the combined effect of a building crisis linked to the economic slowdown, and regulations introduced by the State », for Pierre Friedlingstein, of the Systems Institute in Exeter, who led the study, induces a decrease of -2.8% on a global scale.
In general, Chinese emissions are increasing only very slightly (+0.2%), and “ we can hope that China has reached its peak in fossil fuel consumption », he wants to believe. With a third (32%) of global emissions, China's shifts in whatever direction have a great impact on global developments, as the examples of cement and coal illustrate.
Trump's re-election: an impact difficult to anticipate
American emissions (13% of the world total) decreased by -0.6%, a drop partly attributable to the substitution of coal by gas. It is difficult to precisely anticipate the consequences of the election of Donald Trump. Even if the general tone has not been optimistic for a week, we can assume that he will not completely unravel the IRA (Inflation Reduction Act), this policy favorable to green technologies which has already created 330,000 jobs and attracted more than 370 billion in investments in the United States. But there is no doubt that it will revive the exploitation of fossil fuels curbed by the Biden administration, particularly in the Arctic in Alaska and in the Gulf of Mexico.
As for the consequences for the rest of the world, if everyone recognizes that the shadow of his re-election hangs over COP29 in Baku, “ we don't see what the Chinese would gain from slowing down, when their green technologies are on the verge of hegemonically reigning over markets around the world. », Estimates Pierre Friedlingstein. “ Even for Europe, I want to believe that it is too late to turn back. »
How to limit carbon transitions like in India
On the other hand, the example of India (8% of global emissions), which sees its emissions increase by + 4.6% due to its very carbon-intensive energy mix, perfectly illustrates the need to mobilize funds from developed economies. to finance the transition and adaptation of developing countries. Objective: to guarantee them a less carbon-intensive trajectory than ours, otherwise it would reduce our own efforts to nothing. And this is where American influence risks weighing heavily in Baku, where the main objective of the COP29 which is being held there until November 22, is to find a new financial objective to replace the one which committed the countries ” of the North” to pay 100 billion dollars per year to “Southern” countries between 2020 and 2025. An amount which experts recognize should be multiplied by ten.
The European Union, which recorded a spectacular drop in its emissions of 8% in 2023 (5.8% for France), is doing less well this year (-3.8%), but is still among the best performers.
After a slowdown directly linked to COVID, emissions from aviation and maritime transport, counted separately because they are not included in the national emissions of States, are increasing again by +13.5% and +7 respectively, 8%, while remaining 3.5% below their pre-Covid level. “ Apart from a few national initiatives on domestic flights, which are already not easy to implement, we see no desire to reduce traffic », Regrets Pierre Friedlingstein.
Preserve natural carbon sinks at all costs
Emissions linked to changes in land use (forests, agriculture, etc.) have decreased by around -20% over the last ten years thanks to the slowdown in deforestation. Year in and year out, reforestation absorbs around 50% of the emissions linked to these practices. However, the absorption capacity of forests has decreased by -27% over the last decade. As for their lower performance in 2024, it is mainly explained by the El Niño phenomenon (active in 2023 and early 2024), which increases drought and heat, particularly in South America and Southeast Asia, and by several megafires, particularly in Brazil and Canada “ not all of which are attributable to climate change », according to Professor Pierre Friedlingstein.
« Over sixty years of observation, the fraction of emissions absorbed respectively by the atmosphere (50%), the biosphere (30%) and the oceans (25%) remains constant, reassures the professor. This is why it is imperative to preserve these natural wells. » Especially since for the moment, the absorption capacities of technological carbon sinks (including carbon capture/storage) only absorb one millionth of the emissions linked to fossil fuels!
Another glimmer of hope: the decoupling between economic growth and emissions which seems to be emerging since 22 countries, representing almost a quarter of global emissions, experienced a drop in their emissions and a concomitant increase in their GDP in 2024.
