[REFLEXIONS] Climate change: from awareness to governance

From scientific forecasts to political challenges

The fact that climate change is caused by human activities has been suspected since the end of the 19th century. In 1896, Svante Arrhenius stated that carbon dioxide (CO2), emitted in large quantities since the Industrial Revolution, was accumulating in the atmosphere and contributing to the greenhouse effect, with a consequent shift in the Earth's thermal balance. Numerical climate modelling, which appeared at the end of the 1970s, provided a striking confirmation of these premonitory insights. Since then, the Earth sciences have not ceased to provide new evidence of global warming, from the polar ice caps to the tops of the Andean glaciers. 

In 1979, politicians took up the subject for the first time. The White House commissioned the American Academy of Sciences to produce a "synthesis of knowledge on the possible impact of human activities on climate". The resulting Charney Report highlighted the role of fossil fuels and land use, and warned of the risks associated with climate change. It's only in 1988 that the IPCC was created within the framework of the United Nations, with the aim of "establishing a diagnosis of the potential role of human activities on climate". The publication of the first IPCC report in 1990 paved the way for the United Nations Framework Convention on Climate Change (UNFCCC), the "Climate Convention" adopted at the "Rio Earth Summit" in 1992, along with the Convention on Biological Diversity (CBD) and the Convention to Combat Desertification (CCD). The UNFCCC entered into force on March 21, 1994 and has since been ratified by 198 countries, known as Parties to the Convention. Its ultimate objective is to stabilize greenhouse gas emissions "at a level that would prevent dangerous anthropogenic interference with the climate system".

Global governance of climate action

The foundations for global governance of climate action have been laid. Through the Climate Convention, the various nations have committed themselves to take "precautionary measures to anticipate, prevent or mitigate the causes of climate change and limit its adverse effects". Their political decisions will be based on the recommendations of the IPCC, two of whose working groups are devoted to the crucial issues of adapting societies to climate change and mitigating its anthropogenic causes: greenhouse gas (GHG) emissions. The third axis is the collection and synthesis of scientific information.

Thus, in 1997, the signatory countries of the Kyoto Protocol committed to reducing their GHG emissions, with individualized quantified objectives depending on the level of economic development. It is up to each country to implement the appropriate policies and measures to reach its objectives, provided that it provides annual reports. In addition, mechanisms allow "least developed countries" to continue their economic development while limiting the increase in their emissions. 

Signed at the 2015 Conference of the Parties (COP21) , the Paris Agreement lays a new foundation to fight climate change. "While the Kyoto Protocol was prescriptive, the Paris Agreement is legally binding," emphasizes Ekaterina Ghosh, a student in the Economics for Smart Cities and Climate Policy Master's program at École Polytechnique (a member school of Institut Polytechnique de Paris ), "even though countries set their own targets, they commit to best mitigation efforts in what are called their NDCs (Nationally Determined Contributions), which they must update every five years. In addition, all nations are called upon to join this common cause.  

This ambitious agreement aims, among other things, to keep the temperature rise below 2°C (compared to the pre-industrial era) and even to limit this temperature rise to 1.5°C.  "Global temperature will stabilize when carbon dioxide emissions reach zero net emissions," explains Philippe Drobinski, director of the Energy4Climate center of Institut Polytechnique de Paris (IP Paris). For a climate warming threshold of 1.5°C, this neutrality objective must be reached in the early 2050s."

The declination at different levels

Considering the lower reductions in greenhouse gas emissions required from developing countries, developed countries are called upon to achieve neutrality as quickly as possible. For example, the European Union has committed to reduce its emissions by 80 to 95 percent by 2050, compared to 1990 levels, far better than the 50 percent reduction in global GHG emissions called for in the Paris Agreement. As Patricia Crifo, professor of economics at École Polytechnique (IP Paris), points out, "more and more countries are committing to net-zero emissions targets by mid-century and to strengthening their nationally determined contributions (NDCs) by 2030." 

Nevertheless, progress is not always up to the commitments. Patricia Crifo sums up the situation: "Each country is going through the inevitable process of determining the most effective policies in a changing national and international context. The urge to find solutions continues to grow, and while countries have certainly shown progress in their actions and ambitions, current national climate commitments are still not sufficient to meet the goals of the Paris Agreement. Additionally, while countries need to 'scale up' their commitments, many are struggling to meet their current targets."

"Especially, warns Rajendra Shende, Founder and Director of Green TERRE Foundation, former Director of the United Nations Environment Programme (UNEP), that if the financial commitments made by developed countries to developing countries, a cumulative total of $1,000 billion between COP15 and COP27, are not met, the climate agenda will not move forward."

Energy transition, carbon tax and markets, green finance, civil society involvement, climate action is multifaceted. Find out more about these themes during the REFLEXIONS conference which will take place on June 9 on the campus of Institut Polytechnique de Paris.