Seven years after the last evaluation, this new IPCC report falls in the midst of an avalanche of disasters which put the impacts of climate change back on the front page, from exceptional precipitation in China and Germany to frenzied temperatures in Canada.
“For years, we had warned that it was possible, that all of this was going to happen,” insisted the UN climate manager, Patricia Espinosa, during the opening ceremony on Monday.
Less than 100 days before Cop26 in Glasgow (Scotland), in November, “I say this to decision-makers: science does not allow us to see the world as we would like it to be, it shows the world as it is. . It’s not politics, it’s reality, ”she added.
And “the reality is that we are not on track to meet the objective of the Paris agreement to limit global warming to + 1.5 ° C by the end of the century. In fact, we are on the opposite path, we are heading towards more than + 3 ° C. We must urgently change direction before it is too late, ”she insisted.
“This assessment report is crucial for the success of the Glasgow climate conference,” added the head of the World Weather Organization, Petteri Taalas.
Despite the shock of the images of disasters, some fear that the renewed interest in the climate will only be fleeting as actions crucial for the future of humanity are demanded from the leaders of the planet during this postponed meeting of one year because of covid-19.s
“As soon as these tragedies are over, we will probably forget again and continue as before”, was particularly worried; on Twitter, activist Greta Thunberg, who has dragged millions of young people into the streets in recent years to demand that governments drastically and immediately reduce greenhouse gas emissions.
“Science does not allow us to see the world as we would like it to be, it shows the world as it is. It’s not politics, it’s reality ”.
The IPCC report, expected on August 9, whose “summary for decision-makers” will be negotiated line by line behind closed doors in virtual for two weeks, must update its assessment and its climate forecasts: increase in global temperature, rising sea level, intensification of extreme events.
Two other sections are due to be published in early 2022. The one on impacts shows how life on Earth will inevitably be transformed within thirty years, or even sooner. But it will not happen until after Cop26.
By signing the Paris Agreement in 2015, almost all the countries of the planet committed to reducing CO2 emissions to limit warming “well below” of + 2 ° C compared to the pre-industrial era. , if possible + 1.5 ° C.
Stay under + 1.5 ° C?
While the planet has already warmed by around 1.1 ° C and each fraction of a degree more brings its share of additional extreme events, this threshold of + 1.5 ° C has since become the priority objective of many activists and political leaders.
But can we do it? This is one of the questions that should be answered by the IPCC’s assessment of thousands of the most recent scientific studies.
While some doubt that the challenge can be met, others – sometimes for fear of discouraging – insist that it is not impossible.
“Limiting warming to + 1.5 ° C is still physically, technically and economically possible. But not for long if we continue to act too little and too late, ”says Kaisa Kosonen of Greenpeace.
“The IPCC told us what the ambition should look like: that every country in the world commits to carbon neutrality and details the plan to achieve it”, insisted on Monday, Joyce Msuya, deputy executive director of the UN Environment, when the negotiations kick off.
To hope not to cross the threshold of + 1.5 ° C, emissions should be reduced by 7.6% on average each year, between 2020 and 2030, according to the UN.
And while 2020 has seen a drop of this magnitude due to the covid-19 pandemic, a rebound is expected. And the International Energy Agency even predicts record emissions by 2023, given the low share of stimulus packages devoted to clean energy.
“But if we don’t succeed, if we can reach 1.6 ° C, it’s better than 1.7 ° C, and 1.7 ° C, it’s better than 1.8 ° C” , notes climatologist Robert Vautard, one of the authors of the IPCC.
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