“There will be no collapse”: an “inevitable” warming of 1.5°C, and after?

There will be no collapse an inevitable warming of 15°C

His words challenged us. A few days ago, during an interview with Patrick Pouyanné conducted by L’Express, the boss of TotalEnergies confided his feelings on the world’s ability to achieve the climate objectives set by the end of the century. “I think the scenarios of warming limited to 1.5°C to 2°C are achievable in the long term, but probably not without exceeding this target by 2050”. According to him, the world could then regain this objective at the end of the century thanks to negative emissions, in other words the capture of carbon in the atmosphere. A thesis that is not far-fetched. In the latest IPCC report, the authors also mention this possibility, with, in the most ambitious climate scenarios, the idea of ​​a more or less slight “overshoot”, i.e. a temporary crossing of the target set by the agreements of Paris, before returning to the same objective for 2100.

A path that now appears to be certain. The world, which has already warmed by more than 1.1°C since the pre-industrial era, is all but on the climate trajectory leading us below the fateful two-degree mark of the Paris Agreements. Barring a sudden and massive acceleration of the energy transition, scientists expect the 1.5°C mark to be exceeded within the next decade. Of course, the latter is an “arbitrary value”, remarks Sophie Szopa, research director in atmospheric chemistry at the CEA and expert with the IPCC.

“There is no collapse if we exceed this target. We will have to do everything to limit warming to 1.6 degrees, then to 1.7 degrees because with each additional fraction, it is infrastructure but above all lives people and ecosystems that will be lost”. In other words, the fight for every tenth of a degree counts. And that’s probably why, while the COP27 which opened last Sunday in Sharm el-Sheikh in Egypt hardly bodes well for major progress after the failure of Glasgow last year, that some are preparing for the battle after 1.5°C.

An excess commission

This is the case of Pascal Lamy. Since May 2022, the former president of the World Trade Organization, has taken the head of the World Commission on the management of risks linked to climate overshoot, the “Climate Overshoot Commission”. Its role – as well as that of the 15 commissioners enlisted throughout the world and in particular the countries of the South, among which there are many heads of state, former ministers, leaders – is relatively clear. The aim is to manage the risks of exceeding climate objectives. “We have to prepare for it, explains to L’Express the one who remains president of the Paris Peace Forum. Many scientists tell us that the range is being reduced at the top as well as at the bottom, somewhere between 2° C and 2.7-2.8°C”, he explains, before specifying the meaning of his action. “We need to open up and discuss all the options in front of us. Today, we are looking at three of them: adaptation to climate change, capture and removal of carbon in the atmosphere, geo- engineering and in particular the modification of solar radiation”, he explains.

Fixing more than preventing climate change… inevitably, this raises legitimate concerns. “What the IPCC group 3 report shows is that solutions exist that can halve emissions by 2030. And that is where we must focus our efforts and make progress as a priority. “, Judge Sophie Szopa. “We must work to reallocate funding, modify energy production methods, food and goods, governance to consider climate issues in all decision-making processes. This does not prevent to do research elsewhere, but let’s not waste too much energy looking for miracle solutions when we know that we have technologies on the shelf that must be deployed today”. Pascal Lamy claims to be completely aligned: “We are convinced that reducing emissions must remain the main compass.”

According to him, the subject of mitigation is nevertheless well framed at the global level. Unlike the consequences of exceeding 1.5°C. Pascal Lamy is not the only one to defend this approach. The Brussels think tank E3G, specializing in climate change, has also just produced a note in which it defends that the idea “governments are not prepared for the social and geopolitical implications” of the various tipping points linked to exceeding the target 1.5°C such as the irreversible melting of the ice cap, the disappearance of certain islands due to rising waters, that of certain corals, or currents such as the Gulf stream which has a major impact on global meteorology .

Multiply the adaptation by 100

The “Climate Overshoot Commission”, which is currently carrying out consultation work with civil society and the support of many experts and scientists, should for its part make its first recommendations by November 2023. To listen to Pascal Lamy, a much of it will be about adapting to climate change. “We need much more investment for adaptation, especially in developing countries, starting with Africa or Latin America. Our economic models will undoubtedly show that the 100 billion dollars we are talking about today are quite outdated. It is a scale 10, 20 or even 100 times lower than what will be necessary to invest.”

Money will also be needed to deploy systems on a large scale to capture and eliminate the CO2 present in the atmosphere to lower the temperature. According to Bloomberg, no less than 22 trillion dollars would be needed to lower the global temperature by 0.1 degrees. That is the equivalent of the entire US GDP in 2018. All this, assuming an optimistic cost, at 100 dollars per tonne of CO2 captured, while manufacturers like Bill Gates are currently working on projects at 600 dollars per tonne. Beyond the cost, there is also the question of technology. “This is a field that we will open up in our work, because there is a problem of technology transfer. It is very good that certain countries or industrialists are at the rendezvous on these uses, but if the others take 20 years to benefit from it, it’s too late”, explains Pascal Lamy. Instead of the artificial method, which is immature and very costly, others favor a scenario aimed at using bioenergy with carbon capture and storage. But as Sophie Szopa points out, “these solutions are based on land use (for reforestation for example, editor’s note) and add additional pressure on ecosystems themselves weakened by global warming.”

The debate is even more heated on the third axis developed by the “overshoot” Commission. The use of geoengineering, in particular the modification of solar radiation in order to lower the Earth’s temperature, is still very controversial among scientists. “The risks posed by these solutions are not sufficiently quantified, it is the order of research today”, continues Sophie Szopa, who also points to the risk of governance around these technologies. “If tomorrow we have the technological means to reduce the temperature, who should press the button? At what ideal temperature should we land? This raises a lot of questions and when we see the difficulty of climate governance on mitigation, we thinks it won’t be easy,” she said.

Here again, Pascal Lamy claims a similar approach but claims to be pragmatic. “Whatever opinion one may have on the climatic or scientific relevance of these technologies, in any case, a sufficiently clear body of rules is needed to tie the hands of a country that wants to use them. We cannot not allow ourselves to look elsewhere by judging that it will not exist. Because these technologies will be in the debate”, still judges the former boss of the WTO. So many questions on the agenda of the future COP?


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