This is a highly anticipated annual review. Even more this year as it falls in the middle of the COP26 in Glasgow, presented as the most important since that of Paris in 2015, in particular because the States must present their climate ambitions revised upwards.
This report is that of the Global Carbon Project (GPC), an international group of 86 climate researchers who, at the end of each year, quantifies the global CO2 emissions for the previous year and estimates those for the year in Classes. A size indicator. CO2 is the main greenhouse gas, which certainly has less warming power than others – methane in particular – but which once emitted persists in the atmosphere for longer. Of the order of several centuries.
The problem then arises of the concentration of CO2 in the atmosphere. “It now reaches 415 parts per million *, an increase of almost 50% compared to pre-industrial levels”, indicates Philippe Ciais, researcher at the Laboratory of Climate and Environmental Sciences (LSCE), which is part of the GPC .
Covid-19 only had the effect of a pause
To limit global warming to 1.5 ° C, we must not only stabilize our annual global CO2 emissions – the new quantity that is released into the atmosphere each year – but drastically reduce them. “Around 6 to 7% per year, until carbon neutrality is reached”, indicates Philippe Ciais, carbon neutrality being the point of equilibrium where no more CO2 is emitted into the atmosphere. that we are able to extract, particularly via natural carbon sinks (oceans, forests, meadows, etc.). “That’s the whole issue of the COPs,” resumes the LSCE researcher. Go from a world where CO2 emissions continue to rise to a world where they start to fall. “
We’re not there yet. And the 5.4% drop in global CO2 emissions of fossil origin recorded in 2020, according to the GPC, should not lead people to believe the opposite. It is above all cyclical, linked to the shutdown of our economies caused by the pandemic. “This drop was indeed strong in the United States and in Europe – of the order of 11% – as well as in India (approximately 7%), but it is less than what we expected, specifies Philippe Ciais . Above all, in China, the sharp drop in CO2 emissions observed between February and April and linked to the confinement episodes was followed by a strong rebound linked to the restart of its economy. So much so that Chinese emissions rose 1.4%, when we predicted a small decline in our previous report. “
4.9% increase expected in 2021
Either way, 2021 should mark a virtual return to pre-Covid-19 trends. In any case, the GPC anticipates, based on preliminary data, a 4.9% increase in global CO2 emissions of fossil origin (from 4.1% to 5.7%), to reach 36.4 billion tonnes. in total. We would then be very close to pre-Covid emissions.
How to explain such a rebound when road transport and aviation have still not returned to pre-pandemic levels and that “continuous progress in the decarbonization of our economies? [essor des énergies renouvelables, début de l’électrification de notre parc automobile…] have been achieved since the adoption of the 2015 Paris Agreement ”, according to Philippe Ciais? The LSCE researcher again invokes cyclical factors. “In 2020, the drop in energy demand mainly dealt a blow to fossil fuels, while renewables (solar, wind, etc.) held up well,” he begins. This year, the reverse seems to be happening. The strong demand for energy is largely supported by fossil fuels. Not so much oil, whose use is expected to remain below 2019 this year, according to the GPC. In contrast, the use of coal and gas is expected to increase more in 2021 than it declined last year.
This is particularly marked in China which, to cope with the electricity shortages it is encountering, is running its coal-fired power plants at full capacity and has reopened mines The GPC thus forecasts that Chinese CO2 emissions will increase by 4 % in 2021 compared to 2020, when they had already increased by 1.4%. They could reach 11.1 billion tonnes (against 10.7 in 2020). China would then represent 31% of global CO2 emissions.
Beware of the return to full speed of road transport and aviation?
But this is not the only significant rebound expected by the consortium of researchers. In India, a country which, like China, relies heavily on coal for its electricity production **, CO2 emissions are expected to increase by 12.6% to 2.7 million tonnes. They would be very close to those expected for the EU by the GPC. Or 2.8 billion tonnes, up 7.6% compared to 2020. 7.6%, this is also the expected increase for the United States, also in the list of the main CO2 emitting countries . Its emissions should then amount to 5.1 billion tonnes.
So much for the overview of the main CO2 emitters. Little consolation: emissions from India, the EU and the United States should remain below 2019 levels. A finding that applies, overall, to the rest of the world, observes the GPC. But that could be quickly swept away in 2022 if coal consumption does not drop and if, at the same time, road and air transport return to their pre-Covid level. Another proof of the need to make this COP26 a success.
* That is to say 415 molecules of CO2 for 1 million molecules of air
** Coal accounts for 73% of India’s electricity production. It’s 65% for China.
Land use change also to be taken into account
Until now, we have only mentioned CO2 emissions of fossil origin. That is to say those related to the combustion of fossil fuels used in the world for transport, heating, industries, electricity production … There is yet another way to generate CO2 emissions and that the Global Carbon Project also takes into account in its global balance sheet. It is the change in land use, for example when deforesting to develop new cultivated land.
This change in land use is complex to determine and the estimates on this aspect therefore involve a greater share of uncertainties. In particular, it is not limited to gross CO2 emissions. “When you cut down a primary forest, there is obviously an immediate loss of CO2 [que les arbres coupés avaient stockés] as well as a delayed loss, the litter and the soil continuing to decompose for several years, begins Philippe Ciais. But there is also, in many places of these deforested parts of the regrowth and therefore, again, of the capture of CO2. Finally, this change in land use does not only result in deforestation. It is also necessary to add in the equation the changes of use of the opposite grounds, in particular when agricultural lands are abandoned and give way naturally to the forest. “This is particularly the case in Russia and in Europe where the forest continues to increase in surface area”, indicates Philippe Ciais.
The Global Carbon project estimates in total that net global CO2 emissions linked to climate change from land amount to 4.1 billion tonnes per year over the last decade. The estimate starts from the gross emissions linked to these changes in use (14.1 billion tonnes) from which the tonnes of CO2 absorbed by soil regrowth (9.9 billion tonnes) are subtracted. These 4.1 billion tonnes are then added to the 36.4 billion tonnes of CO2 of fossil origin. Total emissions could therefore approach 40 billion tonnes in 2021. This figure has been relatively stable over the last decade with an average of 39.7 billion tonnes, indicates the Global Carbon Project.