Experts’ reports on the climate emergency are proliferating. Where do we currently stand? Jean-Marc Jancovici: The intense “development” that our species went through in the 19th and 20th centuries was essentially based on the growth of abundant, seemingly limitless energy, accessible at low cost. This energy was fossil fuels (oil, gas and coal). Thanks to these fuels, we were able to provide people with an army of mechanical slaves, ranging from mills to container vessels, and tractors to cranes, as well as textile plants, telecommunications networks, etc.
For more than 40 years now, these fuels have accounted for over 80% of the world’s supply of energy, which is constantly increasing, feeding a fleet of machines that does likewise.
J.M.J : As a result, CO2 emissions have seen exponential growth, unhindered by the numerous climate conferences and experts’ reports. These emissions are increasing greenhouse gases, which inject more energy into the climate mechanism and alter it.
This gives rise to changes in temperatures, rainfall, the frequency and intensity of fires, floods, droughts, storms and other “anomalies”, the melting of the ice caps and glaciers causing a rise in sea levels that will exceed several meters and, in the end, harsher living conditions for a growing proportion of the world’s population.
Is it too late to act?J.-M. J.: Since excess CO2 will remain in the atmosphere for a very long time, the consequences will continue to intensify long after we have started to lower emissions. Consequently, when we are at a standstill, it won’t be enough to just move into first gear, we need to go straight into fifth.
Very clearly, to meet the target of limiting global warming to below 2 °C, we need to start lowering man-made greenhouse gas emissions by 4% a year, starting tomorrow.
J.M.J : this would allow a 3-fold reduction in global emissions by the time my children reach my age.
How? By drastically reducing our consumption, and by opting for low-carbon energy sources such as nuclear energy and renewable energies, with the latter often being more appropriate for heating than for electricity.
On a global scale, we firstly need to shut down all power plants running on coal, gas or oil. Domestically, priority actions concern buildings (insulation, low-carbon heating using heat pumps and wood), low-carbon transport (reduction in the weight and power of cars, use of public transit systems, urban development programs, short supply circuits, etc.).
What is the place of nuclear energy in the energy transition?J.-M. J.: Based on the fission of a nucleus, rather than on the combustion of organic residues (fossil fuels), nuclear energy is one of the low-carbon energies (despite the emissions linked to upstream and downstream operations) with emissions