The year 2020 ended at 1.25 ° C above the pre-industrial period -
PHILIPPE HUGUEN / AFP
The year 2020 joined 2016 on the highest step of the hottest years in the world, in apotheosis of a decade of record temperatures which still testifies to the "urgency" to act against warming, according to the European service Copernicus on climate change (C3S).
The year 2020 ended at 1.25 ° C above the pre-industrial period, just like 2016. But "it should be noted that 2020 equals the record of 2016 despite a cooling of La Niña", insists the C3S service .
And again, there was a La Niña phenomenon ...
The year 2016 was marked by a strong El Niño episode, a natural oceanic phenomenon that causes a rise in temperatures.
According to NASA and the World Weather Organization (WMO), El Niño would have contributed between 0.1 and 0.2 ° C to the global temperature of 2016.
"It is quite clear that in the absence of the impacts of El Niño and La Niña on the temperature from one year to the next, 2020 would be the hottest year on record," Zeke assured AFP. Hausfather, a climatologist at the Breakthrough Institute, noting that the world has gained 0.2 ° C per decade since the 1970s.
The WMO, which is due to publish consolidated figures shortly by combining data from several official agencies, said at the end of December that 2020 would rank among the three hottest years.
Plus 6 ° C in the Arctic compared to the reference average
In Europe, marked by an exceptional heat wave, the year 2020 was by far the warmest, 0.4 ° C above 2019, and 1.6 ° C above the reference period 1981-2010, i.e. more than 2.2 ° C above the pre-industrial period.
This warming is already exceeding the objectives of the Paris Agreement.
But these goals are for the entire planet and it is known that the lands are warming faster than the oceans and that some regions are warming much faster, such as the Arctic, where temperatures in 2020 were 6 ° C above the reference mean.
In this same Arctic region, particularly in Siberia, the year was also marked by an “exceptionally dynamic” forest fire season, releasing 244 megatonnes of CO2, or “more than a third more than the record of 2019” .
At least 1.1 ° C gained compared to the pre-industrial era
Beyond a single isolated year, the 2015-2020 period is the hottest on record and the last decade (2011-2020) is also the hottest since the start of the industrial era.
"It is no surprise that the past decade has been the hottest on record, and it reminds us once again of the urgency to ambitiously cut emissions in order to prevent adverse climate effects in the future." , underlined in a press release Carlo Buontempo, director of C3S.
These harmful effects are already being felt across the planet, from melting sea ice to exceptional heat waves, through torrential precipitation or the last record hurricane season in the Caribbean.
And the worst is yet to come.
The planet has gained at least 1.1 ° C compared to the pre-industrial era, with already its share of climatic catastrophes.
But despite the objectives of the Paris Agreement to keep warming well below + 2 ° C, if possible + 1.5 ° C, the states' current commitments to reduce greenhouse gases are still far from this. path.
The concentration of CO2 in the atmosphere continued to increase
Despite the measures taken against the Covid-19 pandemic and the slowdown in the economy which led to a record drop in CO2 emissions in 2020 (-7% according to the Global Carbon Project), the concentration of CO2 in the atmosphere continued to increase, according to satellite data from Copernicus.
Reaching "an unprecedented high" of 413 ppm (parts per million) in May 2020.
“While carbon dioxide concentrations increased slightly less in 2020 than in 2019, there is no need to rest on our laurels.
As long as net global emissions are not reduced to zero, CO2 will continue to accumulate in the atmosphere and cause further climate change ”, warned Vincent-Henri Peuch, head of the monitoring service of the atmosphere of Copernicus.
“CO2 accumulates in the atmosphere like water in a bathtub.
If the flow rate of the tap is reduced by 7%, the level increases more slowly but it continues to rise.
We have to turn off the tap to stabilize the climate, ”Stefan Ramstorf of the Potsdam Institute for Climate Impact Research told AFP.
CO2: Global emissions fell in 2020 under the effect of confinements ... but only 7%
Forest fires: “Unprecedented” episodes in 2020, but overall downward trend according to Copernicus