After more than a century and a half of economic development devoting fossil fuels, the world has gained approximately +1.1°C compared to the pre-industrial era, already multiplying heat waves, droughts, storms or devastating floods.

In the first part of their report published last August, UN climate experts (IPCC) estimated that the mercury would reach around 2030, ten years earlier than expected, the threshold of +1.5°C, most ambitious goal of the Paris Agreement.

Before a third opus in April on solutions to reduce greenhouse gas emissions, the second, whose negotiations begin on Monday, looks at the impacts of global warming, and how to prepare for it ("adaptation") .

It must decline these consequences on all continents and in all their aspects: health, food security, water shortage, displacement of populations, destruction of ecosystems...

Rising temperatures in the world since 2002 Kenan AUGEARD AFP

"Life on the planet is being hit by climate change and many systems are reaching their limits (...). We too have our limits. Like other species, our living space is shrinking", commented a few years ago Hans-Otto Pörtner, co-chairman of the group of almost 300 scientists who prepared this report.

A preliminary version of this text, which AFP had obtained last June, showed that life as we know it would inevitably be transformed, in the short term.

On almost all continents, the world is already seeing with its own eyes the disasters at work.

Like last year with the flames ravaging the American West, Greece or Turkey, floods submerging regions of Germany or China, or a thermometer that comes close to 50°C in Canada.

"Good kick to the..."

Faced with this observation and the need to reduce emissions by nearly 50% by 2030 so as not to exceed +1.5°C, the world promised at COP26 in Glasgow in November to step up the fight against global warming.

“Not enough” to ward off “the climate catastrophe which is always knocking at the door”, then reacted the Secretary General of the UN Antonio Guterres who calls in particular for the exit from coal.

The Neurath thermal power plant, in Germany, on January 17, 2022 Ina FASSBENDER AFP / Archives

As states are called upon to step up their ambition by COP27 in Egypt at the end of 2022, "I hope this report will be a good kick where I think for some," the envoy told AFP. American for the climate John Kerry.

Even if "we should not need disturbing new statistics to know what to do".

This new assessment of the IPCC will be unveiled on February 28, after two weeks of virtual meeting of the 195 Member States who will sift through, line by line, word by word, the "summary for decision-makers", a politically sensitive summary of thousands of pages of the complete scientific report.

Evolution compared to the previous report of seven years ago, the attention paid to "adaptation", that is to say the solutions to deal with the impacts of climate change.

"The focus on (adaptation) solutions is not just a shopping list of what could be done, but also an assessment of the effectiveness and feasibility" of the measures, the other co explained. -President of the IPCC group Debra Roberts.

After the passage of cyclone Batsirai in Mananjary, Madagascar, on February 8, 2022 RIJASOLO AFP / Archives

But "there are limits to adaptation," said climatologist Laurent Bopp, one of the authors of the report, to AFP.

"In some areas, if the temperatures exceed very high levels, human life is no longer possible. If in some coastal areas the sea level rises by more than one meter, protection with dikes is no longer possible. not possible either. So in some scenarios, we can expect large population migrations,” he adds.

Scientists and NGOs call for all necessary decisions to be taken to limit irreversible consequences as much as possible.

With the new report, "the reality of those living in the most vulnerable situations will be impossible to ignore," hopes Kaisa Kosonen of Greenpeace.

"The indisputable facts that will be presented will make the lack of action and commitment by major emitters more evident, and the calls for justice even stronger."

© 2022 AFP