The chimneys of the Jeffrey Energy Center coal-fired power station in the United States.
Charlie Riedel / AP / SIPA
As at the end of each year, the Global carbon project (GPC), an international consortium of 86 researchers, publishes its annual report on global CO2 emissions.
With a question in everyone's mind this year: what impact has Covid-19 had on global emissions?
The GPC estimates the decrease in emissions in 2020 at 7% compared to 2019. It was even more pronounced in Europe and the United States.
The pandemic therefore made it possible to break the trajectory of continuous annual increases.
“But 7% is still too little to have any impact on the concentration of CO2 in the atmosphere,” underlines climatologist Philippe Ciais.
At the end of each year, in the run-up to the COPs, these UN summits dedicated to climate, the Global carbon project (GPC), an international consortium of 86 researchers, publish the estimated annual assessment of global CO2 emissions from the previous year, related to human activities.
In other words, in the article it publishes this Friday, the Global carbon project should have dwelled on 2019. In the end, it was hardly mentioned during the decryption prepared this Thursday by Philippe Ciais, researcher at the Laboratoire des Climate and Environmental Sciences (LSCE), one of these 86 researchers.
Just enough time to recall that in 2019, “CO2 emissions remained more or less stable on a global scale, with an increase of 0.1% compared to 2018”.
An increase, of course, but less strong
To be completely clear, the Global carbon project focuses on carbon dioxide, excluding other greenhouse gases emitted by human activities, such as methane.
And this + 0.1% covers only the so-called fossil CO2 emissions, that is to say linked to the combustion of resources extracted from the ground (coal, oil, natural gas) that we use as energy.
To move, heat, run our industries….
Emissions linked to changes in land use (destruction of meadows and forests), which also release their share of CO2 into the atmosphere, are not taken into account.
All the same, these fossil CO2 emissions are a telling indicator as to whether the international community is on the right path to limit global warming to 2 ° C by 2100 *, as it committed to by signing the Paris climate agreement.
In this + 0.1%, there is better: the annual growth rate of CO2 emissions has weakened compared to the two previous years.
The increase was 2.1% in 2018 (compared to 2017) and 1.5% in 2017 (compared to 2016).
Last year, the Global carbon project anticipated this slowdown by explaining it by two factors.
On the one hand, the economic performance of China and India weaker than expected, which reduced the demand for electricity from these two large emitters.
On the other hand, the worldwide decline in the use of coal, an energy with a heavy carbon footprint.
“The main enemy today in the fight against climate change,” slips Philippe Ciais.
A drop of at least 7% predicted for 2020
And for 2020?
To tell the truth, it is especially on this vintage, so unprecedented due to the Covid-19 pandemic, that the GCP is extending this year.
With a big question: what impact have the lockdowns had on global greenhouse gas emissions?
"The various methods developed to try to measure this phenomenon allow us to conclude that there is a decrease of 7%", indicates Philippe Ciais.
This decrease is pronounced in the United States (- 12%), in the EU (- 11%) and in India (- 9%), notes the Global carbon project.
In these regions, the effect of restrictions linked to Covid-19 comes on top of a previous trend marked by a decline in coal in favor of natural gas, which emits less greenhouse gases.
“This trend continued in 2020, with natural gas remaining inexpensive,” explains Philippe Ciais.
Conversely, the drop in emissions was less pronounced in China (- 1.7%), where restrictive measures were taken at the start of the year and were more limited in time.
“By April, Chinese emissions had recovered to the levels of previous years,” observes Philippe Ciais.
These estimates remain provisional.
The GCP must publish new figures by the end of the week taking into account the second wave of containment.
"But this mainly concerned Europe, not much South America and even less Asia," says the researcher at LSCE.
We may be on a final drop of 8%.
"Too low to have an impact on the C02 concentration"
Good news ?
On the one hand, the pandemic made it possible to break the trajectory of continuous rise.
"But this drop is too small to have any impact on the concentration of CO2 in the atmosphere", specifies Philippe Ciais.
Especially since this concentration does not depend only on the quantities of CO2 emitted each year.
The natural carbon sinks - oceans, soils, forests - also enter the equation, which capture part of the CO2 in the atmosphere *.
Not just a little, "of the order of 54% of emissions", assesses the Global carbon project for 2020.
“These absorption capacities can vary greatly from one year to the next, depending in particular on climatic conditions,” continues Philippe Ciais.
So much so that the 7% drop in emissions recorded in 2020 could very quickly be wiped out.
This decrease is also too small to put us on the path of the Paris Agreement.
Philippe Ciais refers on this subject to the Emissions Gap Report, published Wednesday by the UN.
"He estimates that our current emissions should be reduced by 25% by 2030 to stay below the 2 ° C increase, and even by 40% to be on the path of 1.5 ° C", details- he does.
Some promising signs
However, the Global carbon project does not invite you to see everything in black.
“Five years after the adoption of the Paris Agreement, the growth of global CO2 emissions is starting to run out of steam,” points out the study.
Between 2010 and 2019, they decreased significantly in 24 countries whose economies remained growing.
The global average increase in these emissions over this decade was 0.9% per year - which still represents an increase of 3.3 billion tonnes of CO2 in total.
But the rate was 3% per year the previous decade, between 2000 and 2009.
The Covid-19 pandemic today invites us to go further.
“Even if human activities were disrupted in 2020, they have not stopped either, but have changed, still requiring the consumption of energy, retains Philippe Ciais.
The challenge is therefore not to move towards zero human activities, but to achieve decarbonization.
“An invitation not to miss the recovery plans.
, as the UN demanded this week.
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