Key figure: - 8.6% of world CO2 emissions

A major but non-sustainable reduction of pollution

According to the study published on 19 May in the scientific research journal Nature Climate Change, global CO₂ emissions have fallen in 4 months by 8.6%. At the beginning of April, daily global CO₂ emissions fell by up to 17% in comparison to average levels in 2019. The trend was more or less strong according to country, from -23.9 % in China to -34% in France. Over the year, the reduction should be around 5 to 6%.

According to the American research institute Global Footprint Network, which, every year, calculates “Earth overshoot day” (the theoretical day from which humanity consumes all the resources that ecosystems can produce in one year), 2020 will see this fateful day postponed for three weeks, to 22 August, due to global confinement measures.

Unfortunately, this reduction, unseen since the Second World War, will not be sustainable. Indeed, this spectacular fall is mainly due to the health crisis caused by Covid-19, which has led to a radical decrease in air and road traffic, fossil fuel production and industrial activity. However, economies around the world are progressively resuming their activities. It is highly likely that we will rapidly return to the levels seen before the crisis, especially since the problem is deeply rooted: worldwide, human activities continue to emit 90% more than normal CO_2. emissions.

This shows that major and rapid changes are possible. But this reduction of our ecological footprint is imposed and unwanted, and since it is not accompanied by a systemic transformation of our modes of production and consumption, it won’t last, according to Mathis Wackernagel, the President of Global Footprint Network.

Awareness of the changes to be made

For Corinne Le Quéré, climatologist and main author of the study, the foremost interest of these indicators is that they provide an idea of the magnitude of the measures that have to be taken to limit GHGs and motivate structural changes to globally rethink the combat against climate change.
According to Jean Jouzel, also a climatologist, as well as glaciologist and former Vice-President of the Intergovernmental Panel on Climate Change (IPCC), the objective of limiting climate change to 1.5 or 2 degrees cannot be reached unless this reduction scenario is repeated every year until 2030. Indeed, it is the accumulation over decades of carbon dioxide in the atmosphere which is driving rising temperatures, and this quantity of CO₂ will be modified only infinitesimally by the reductions of emissions this year.

However, the urgent need to relaunch economies currently weakened by Covid-19 risks taking precedence over environmental and climatic concerns.
According to the ten-year climate forecasts of the World Meteorological Organization (WMO), average world temperatures should exceed a record between 2020 and 2024, with a direct impact on ocean warming, in particular the Austral and North Atlantic Oceans. It is therefore crucial that relaunching plans place the climate issue at the forefront of their priorities:

The way in which leaders take climate change into account in their economic responses to this health crisis will have an impact on trends for global CO₂ emissions for decades to come, says Corinne Le Quéré.